Another JBL bypass question

Hey y’all, this is my first time posting on a forum ever, so forgive me if this specific issue has already been addressed. I’ve looked extensively at many posts about the aftermarket audio JBL bypass things and can’t seem to mush together enough info to make sense of my problem.

To start, I’ve got a 2004 double cab with the factory JBL system. I installed the

$39 Metra 70-8117 Factory Amplifier Harness for 2004-Up Toyota Vehicles with JBL Sound System

Metra 70-8117 and ian Alpine ILX-w670. I had sound from all 4 doors, and it sounded much better than before install. I was happy, but planned on installing some basic kicker 6 1/2s up front and 5 1/4s in the back, to be powered by a new 4 channel JBL Club A754 amp.

Yesterday I attempted to install the speakers and then if time permitted, install the amp. I pulled the door panel off, disconnected the woofer/mid assembly and tried to use the plug the the new kicker with the 72-9301 speaker harness from Crutchfield. Once plugged in I turned everything on to check it and only got sound from the mid and the tweeter. Figuring I messed up the plug because it didn’t fit well, I tried to hook the old woofer back up and tested again. No sound from woofer, but sound from the mid and tweeter still. Frustrated and out of time I buttoned it all back up to try again later.

Today I pulled the passenger front door off, which I hadn’t touched yet, to see if I had sound from the woofer. No sound from the woofer, but mid and tweeter working.

So I called crutchfield to see if they could help and they said the wiring I did initially from the amp bypass to the head unit was off. I hadn’t connected the white/red (wr) wire, the green/white (gw)wire, the brown/yellow (by)wire or the brown/blue (bb) wire. Said should be wr spliced/added to white/black wires, gw spliced/added to solid white, by spliced/added to solid grey, and bb spliced/added to grey black. he said wr was driver +sub, gw was driver -sub, brown/yellow + passenger sub, brown/blue - passenger sub.





So I clipped the connections and added in the above wires, and still no sound from either front subs, still only mids and tweeters.



Pardon the mess and the temporary splice hack job. I just wanted to see if I got sound from the woofer

There is also a post from @shifty` earlier about how to connect just the front speaker, without the tweeter. Which I think was what I did before I called crutchfield, but I can’t remember exactly.

I’ve already been redlining my limited skills/knowledge with everything up to this point. Now I can go two directions.
1. wire up the new amp to the assumed incorrectly wired harness only to have the speakers still not play. I’m guessing I did something wrong/stupid and hoping it’s a quick fix.
2. Say fuck it, install the new amp and do it like the old days and run speaker wires directly to the doors from the amp.

I’ve read so many posts about this stuff and even more of @shifty`responses, including the opinion on kicker speakers (bought them before reading that post and don’t wanna send more shit back to crutchfield) but I’m hoping someone can clear this up for me or point me in the right direction as far as how I should proceed. Any help is appreciated!

 

The difficult part about helping with the DC JBL system is, quite simply, the convolusion of the wiring, and the impedance of the speakers.

The front door has two separate channels, carried by two pairs of wires:

• One direct to the woofer, which arrives via 2 wires of the 4-wire conector on the lower 2-speaker housing
• One indirectly to the tweeter above and non-woofer in the 2-speaker housing (on the other 2 wires)
• The latter pair, the wiring comes into the door, goes up to the white connector a few inches below the tweeter mount, where it then routes one pair up to the tweeter, and loops back another pair down to the non-woofer in the 2-speaker housing's 4-wire connector.

Of those 3 door speakers, they have weird wiring/impedance:

• The tweeter/lower-non-woofer speaker are both 4ohm each, wired in parallel, making that circuit a 2ohm load
• The woofer itself is 2ohm also
• The rear door is also a 2ohm speaker too, on its own rear channel, meaning you have three total speaker channels per side at 2 ohm, or 6 total 2ohm channels

Why am I telling you this?

2ohms on a single channel is a significant load for many amps, and can overload/blow channels on some radios. When you use the Metra bypass harness, if you leave the OEM speakers intact, the harness is having to take the front door's two (separate) channels per side, and bridge those down to a single channel UNLESS you make some wiring mofidications and stray from the instructions Metra and Crutchfield provide.

Crutchfield (IIRC) is pretty explicit that you either (A) shouldn't use the bypass harness without upgrading the speakers or (B) should only use the bypass harness if you upgrade the factory speakers - but I don't recall off the top of my head which one it is.

Anyway, I think the big thing is this:

1. You have no sound to the lower woofer in the door.
2. I see you have random wires electrical taped together in your pics, and the butt-spliced wires are improperly stripped, with wiring outside the splice
3. I would urge you to "tug test" all of your wires that are butt spliced before you make another move, to ensure you don't have a loose/dead connection based on my previous comment #2
4. If all are intact, you have a spare set of speakers in your hand, whatever you purchased to install in the door (or you removed), you can easily intercept a pair of the speaker outputs from the Alpine harness (green pair/purple pair/white pair/grey pair) and temporarily run one pair to the woofer to test (A) the Alpine is sending output to the front channel and (B) the speaker you're trying to use is, in fact, OK

I'd probably start there - cut only one pair of those for channels, attach to speaker, verify Alpine is outputing a speaker-level signal to a test speaker. Repeat with each additional channel, ensuring you NEVER leave a copper channel exposed and NEVER cut a + and - wire at the same time (the cutters will bridge the two wires together and fry something).

Once you validate the Alpine's channels are outputting alright, and the speakers you're using are OK, THEN we can proceed with figuring out what's up. It's entirely possible there's something else at play here, but we need to get to the basic answer of: "Did I fry something here?"

 

Thanks for getting back to me so quickly. I’ve got a toddler and a new baby so I can only work on things at night. I did as suggested:

1. tug tested my temporary butt-spliced wires, all good. No movement. The poor butt splice job was just to hold them all together while I tried to trouble shoot. Same with the electrical tape, just temporary to hold things together while I followed crutchfield’s instructions. I ended up putting the twist caps on each until I figure out what’s what, and then I’ll clean it all up, solder, heat shrink and wrap.

2. Next I went through each of the speaker outputs from the Alpine harness and all worked. I’m curious what it accomplished other than making sure the kicker speaker worked. There was always power to all 4 doors but for some reason the power wasn’t going to the woofer of the fronts. To me that lends to the problem possibly being related to what crutchfield was suggesting, that an additional wire wasn’t included to the front L and R connections I originally made.

If I have power and sound going to the mid and the tweeter, which from my understanding of what was written above about the wiring, are tied together somehow, is it possible to just use the power going to them, and use that to power the new speakers?

The explanation above about how Toyota’s convolution of wires is above my novice level of understanding what’s doing what to whom, but I follow that it’s not wires going from on place and directly terminating at another. It makes me reluctant to just snip the power going to the mid and using that to drive the new speaker. That’s what I really want to do, but don’t want to mangle things….but would it work?

I’m running low on time (and my wife’s patience) due to not having a very driveable vehicle and being distracted trying to figure this out so I can put the interior back together. I’m getting tempted to throw in the towel and have a shop finish it up, but I’m conflicted because I loathe quitting and admitting defeat.

Any other ideas? Should I just install the he new amp and run speaker wires from the amp to the doors? Seems straight forward but also very time consuming.

Is there a way to connect the new speakers to the wiring used for the mids?

 

Any time you're troubleshooting an output issue, where something isn't feeding correctly, you always go back to the source. Is it working at the source? If yes, you know your problem is downstream, and you need to keep diagnosing down the line until you find where the signal stops. It also confirms the speakers are functioning, and sound OK, as in they haven't been blown due to miswiring.

Both are a basic principle of diagnostics:

• Verify yVerify your source/input.
• Verify your end component/target.

Now you know the signal is working at the head unit, and its amp isn't fried, I'd head to the next joint upstream. That would be the tie-in to the Metra harness, making sure your wiring pairs are sorted correctly there.

We know you have two channels (four wires) feeding to the front door, to power the (A) woofer in lower doow and (B) the tweeter and 2.5"(ish) mid. That means, for the front channel, the Metra harness is taking 3 channels (6 wires) and paring them down to two channels (four wires) to merge those two frond channels per door down to one.

Given you're only getting sound to one door channel, the tweets/highs, and not the other, the woofer, that tells me you forked something up with that bridging. So I'd like to know the exact wire color pairing you're currently using so I can look at the Metra instructions and verify you didn't screw it up. I suspect you did.

I did put a basic instruction with pictures on here of what the wiring should look, I'd need to find that post. I drew it up in Microsoft Paint to help, since the Metra instructions are overly generic, made to adapt to multiple vehicles which don't share our exact wiring.

 

Ok @Thundrathighs, taken from HERE, this is what I was looking for - can you verify this is your wiring setup?

Be careful on the white w/red stripe wire, and the green w/white stripe wire. Those are the ground for the woofers. Make sure you didn't switch those other two green and white wires with the green-solid/white-solid or green w/black or white w/black or solid white wires! (and make sure you connected correctly). Harder to confuse those than the brown/yellow brown/blue, which are the woofer positives.

​

AND JUST TO "SHOW THE MATH" ON THAT DIAGRAM, HERE'S THE METRA INFO I BUILT THE ABOVE DIAGRAM OFF OF ---

​

 

This is exactly what I used and it worked great with aftermarket speakers.

 

Oh! And one other thing ... **IF** you cut any wires in the door, I may want to see how ou did. I don't think it's necessary in this case, but ... that would be important to the end result.

 

First, I’d like to say thank you for taking the time to help, and respond so quickly. The amount of help you’ve given to people on this site is really cool to see. I appreciate it. Especially considering my knowledge deficit. I’ve learned a ton.

As far my wiring, I would be less than surprised if I fucked it up somewhere. Before I called crutchfield I had:
purple-purple, purple/black-purple/black, green-green, green/black-green/black, white-white, white/black-white/black, grey-grey, grey/black-grey/black. Only the mids and highs worked in front doors.



Per Crutchfield I needed to add white/red to white/black connection (- woofer drivers side), add green/white to white connection (+woofer drivers side), add brown/yellow to grey connection (+ woofer passenger), add brown/blue to grey/black (- woofer passenger). After doing that I still didn’t have power to woofers. I posted those pics with the shoddy temporary connections in my first post.

I found a picture of yours a while ago that differed slightly from instructions:

 

I cut before the connector to the woofer on the drivers door. I cut it after I tried the kicker and then retried the sub without success. I thought maybe the connector they sent wasn’t seating well so I clipped and tried to connect it manually. Passenger side I haven’t touched. I’ll take a pic when I get home.

 

Just saw all the above posts after I sent those last couple. I’ll take a look and get back to you. Thanks again!

 

The picture you just posted was, IIRC, laid out for another member who was doing something special. I believe they were taking the front doors down to one channel vs. two, specifically running their tweeter/2.5" lead to feed a crossover in the door, and piping their crossover out to the new tweeter and woofer. I may be mistaken, bt I'm 90% positive I'm not

I'd like a link to that thread where you got it, if you still can find it. I probably need to put a big ass disclaimer on that reply to mention that point.

The picture I posted in reply #5 is what you will use, it's what Crutchfield and Metra recommend for that 8117 JBL bypass harness. The reply #5 instructions/diagram is what you'll use with the JBL 8117 harness for a fully unmolested system (i.e. all factory door wiring un-cut/unadapted), and aftermarket stereo, when you want to bypass the amp and have your head unit power the speakers. It should work with OEM speakers or with aftermarket, but ideally you should only use the pic.

Please - and seriously, I'm a dad too, I know the time constraints involved, and also having to have your vehicle working in case an emergency trip to hospital or store or whatever is required, DO NOT hesitate to update the thread whenever, and tag me. It's summer so I'm running my teen/tweens around during the day and I'm not always on top of it, but I'll try to stay on top of it.

 

Ok, checked the connections, lots of times. All the wiring and connections match your drawing/diagram above, still no power to either woofer.
Here’s the pic of the sub wires I cut. I realized right after, that after cutting it I should’ve given more room to reconnect if I needed.

At this point I’m more strongly considering just using power from the mid, unless there’s a compelling reason this is ill advised. I’m also guessing because the tweeter and the mid are on the same channel that the tweeter would still be playing while the new speakers are. I imagine that would decrease sound quality, and could also cause other issues? The reason it seems like the logical more time efficient choice is because I’m not using a component system.

I wish I grasped what was going on in a wiring diagram. It looks like alien hieroglyphics.

So if I run the new speakers from the mid’s connections, what issues would I run into?

 

Friends don’t let friends cut OEM wires!

 

To be clear: They match my diagram in reply #5, right?

Not the one you posted in reply #8 which is totally different?

Wire nuts are bad in the car audio world and shouldn't be used for anything other than testing. Only saying this 'in case'.

Yes, that's ill-advised with your current wiring. That little mid next to the woofer is powered on a separate channel from the woofer, by pulling the woofer into its channel which is bound to the tweeter, with or without the little 2.5" mid attached, you will change the impedance/load on that front channel. And in the case of the woofer, with it being a 2ohm speaker, you're going to overload something because the tweeter/2.5" mid are both 4ohm in parallel, which is a 2ohm load. You could maybe wire the woofer in series and it'd be OK, but ... let's not go there.

It depends whether you wire things in series or in parallel.

But before you go there, I really want to see pictures of all of your wiring showing the joins which I'm showing in my reply #5. I want to see how your wires are paired up. Something isn't right, and I just want to sanity check your work. I know the setup I provided in that picture will work, others on here have used it. I'm convinced you've probably mis-crimped a negative or positive lead for the woofers. Specifically, on the Metra harness, these should be your door woofers:

Passenger woofer (-): Brown/Blue
Passenger woofer (+): Brown/Yellow
Driver woofer (-): White/Red on Metra
Driver woofer (+): Green/White
​

In theory, just to test, you should be able to directly attach the matching brown pairs to the corresponding grey pair of the radio, and the matching white and green wires to the correct white pair of the radio, and the woofers will work (but highs shouldn't, because you'd be disconnecting them.

Maybe we test by deleting the front tweeter/mid, and connect the front channels only to the woofers by pairing up the wiring up as follows?

METRA WIRES :<==>: ALPINE WIRES
Brown/Blue str <-----> Gray/Black str
Brown/Yellow str <-----> Gray solid
White/Red str <-----> White/Black str
Green/White str <-----> White solid​

At this point, if we can't figure this out, I'm wondering if the best option isn't running with a component system, and stealing the connection from the tweeter, then using image from reply #8.

 

Have to make a couple edits. But I wanted to add something, in case you don't want to rewire.

There is an old test we used in a pinch at ths shop, and I know DIY'ers use it also to verify a speaker circuit is functional. You need a 9v battery (the rectangular ones).

On a 9v battery, the big terminal is negative, small terminal is positive. In theory, if you hold the negative wire of a speaker terminal onto the negative terminal of a 9v battery, while tapping the positive wire to the positive terminal, the cone should extend, typically with a popping sound. If the cone pops out, and you used the correct terminals, you know (A) the speaker is wired in correct polarity, (B) the circuit is obviously good, and (C) the speaker voice coil is intact, as you should hear a sound associated with it (pop).

I'm posting a video of that test below so you can see what a person would be looking for, but this is what I'd do in your case. We've already seen one case of Metra FUBAR'ing a connector in the last year or two, "no audio" was a result, because the factory moved two pins over into the wrong holes in the connector.

You can verify the Metra harness is correct with a 9V battery as follows:

To test the passenger woofer circuit is functional using the Metra amp bypass, hold the Brown/Blue stripe wire to the negative (large) terminal of the 9v battery, and tap the Brown/Yellow stripe wire to the positive (small) terminal of the 9v. You should hear a pop from the passenger woofer with each tap, and if the door panel is off, you should see the cone extend outward with each tap. (if it pops inward, this means the polarity is incorrect)

To test the driver woofer circuit is functional using the Metra amp bypass, hold the White/Red stripe wire to the negative (large) terminal of the 9v battery, and tap the Green/White stripe wire to the positive (small) terminal of the 9v. You should hear a pop from the driver woofer with each tap, and if the door panel is off, you should see the cone extend outward with each tap. (if it pops inward, this means the polarity is incorrect)

https://www.youtube.com/watch?v=Uv6G-8Hr7NU​

 

Last thought:

Please be sure you're not confusing the brown/yellow stripe wire on the Metra harness with brown/white due to poor lighting or otherwise.
Likewise, make sure you're not confusing the white/red strip wire on the Metra harness with any other wire.

Your Alpine's white/black stripe wire should have the following wires connected: White/red stripe, white/black stripe (from Metra bypass)
Your Alpine's solid white wire should have connected: Green/white stripe, solid white (from Metra bypass)
Your Alpine's grey/black stripe wire should have connected: Brown/Blue stripe, gray/black stripe (from Metra bypass)
Your Alpine's solid grey wire should have connected: Brown/Yellow stripe, solid grey (from Metra bypass)

Effectively, each Alpine white and grey wire (all four, both pairs) should have 3 wires crimped in total.

Note that, if you're using the OEM JBL wires with this configuration, the impedance/load will be high. I don't recommend using this setup with the OEM JBL speakers for very long.

 

Ok, here are the connections I have. I hope they are visible and you can distinguish the colors. Rears:

Not used wires, once everything is done they will heat shrink wrap:


Front speakers with woofer +/- wired in. Checked again to see if working, still no power to woofer. Twist cap connectors only used to temporarily connect. Once working, will appropriately solder/heat shrink:






Below is wiring for woofer test with tweeter/mid deleted - No power to passenger or driver side woofer. Only remembered to snap a pic of the left front, but tested both.


I also tried the 9v pop test to both driver and passenger woofers. No movement to either woofers even with polarities swapped.

I am so stumped. Did I fuck something up this spectacularly? I’m gonna look more closely at the above posts to make sure I didn’t miss anything else to test.

@shifty` I’m not opposed to upgrading to a component system. Better sound is never a bad thing. Would that be a quicker fix? How hard is wiring it and doing the whole crossover thing? I’m hesitant to jump into more wiring after all the fun I’ve had trying figure this out.

 

I'm sure this is one of those things I could easily figure out if I were there and able to put my hands on stuff. But the only thing that makes sense would be, you cut something else in the door you're not showing, or the Metra harness has a factory defect where it's not pinned correctly at one end, which is totally possible, we found a case of this recently that affected multiple people, right here on this forum (with a diff't harness).

So, let's verify some stuff. I'm going to give you a list of things to do, b/c I don't know when I'll be back at a computer today. Note, I'm using Metra's document on the 8117 as reference material to do quick and dirty markup on these images due to time, along with Crutchfield's pinout info.

The only thing that makes sense here, is you did something unfortunate like cut the signal wire to your woofer, or Metra has a pinout problem again.

If it's a "you" mistake, where you cut or attached wires wrong, the two-speaker plastic housing in the bottom of the door has (4) total wires going into it. One pair of those four wires feeds your woofer. The other pair of wires completes the circuit for your tweeter and 2.5" mid. Did you cut any of those 4 wires outside of the enclosure, like, at the outside plug?

In case words are not clear with that ... you didn't touch or cut any of these four circled wires on the whtie side of the connector, right? At any point? (ignore the non-OEM JBL here). Two of those supply signal to the black/green wires to the woofer. The other two are coming from your tweeter to feed the red/yellow wires to the 2.5" mid. If you, by chance, cut of those wires, specifically the green and blue/white stripe pair you can see feeding the green/black on the other side of the connector, it would cause these symptoms.

​

If "NO!" is your answer, then the next question I must ask...

When you cut the black and green wires at the OEM woofer connector to attach your new Kickers into the system. That green OEM wire is GROUND. The other wire (black, IIRC) is POSITIVE. You didn't do something silly, like assuming the black wire is ground, and attach the black to ground terminal on the Kicker, and the green to positive terminal on the Kicker, did you? If you did, it would (at least) explain one thing for me, but not sure it'd explain everything else.

Recapping Metra's documentation. From Metra's document, after parsing out all the Prius, Solara, and Sequoia BS wires, this is what Metra says each wire is used for in your 2004 DC:

​

In theory, you should be able to take any +/- pair of wires from that bundle and do the 9v battery test on them, assuming the 9v battery you used has power (touch both terminals to your tongue and if it doesn't give you a good zap, your battery is bad). I'm not saying you should do either. "I'm just saying".

But the big thing I want you to check is this... I want you to go to the JBL amp.

At the JBL amp side of things

Do me a favor:

Make sure it has an orange JBL sticker on it, so we know it's JBL - I see JBL speakers so I'm assuming it is, but I want to verify everything at this point.
Make sure no wires are loose or cut on either side of the amp or adapter harness, and the Metra harness is fully seated.

Next, I want you to - with the Metra harness attached to the JBL amp harness, still connected - I want you to verify Metra's pinout. To do that, from the back of the Metra connector, orient the wires like this, parting them as-shown, almost like a hairline, so you can clearly see all (20) holes in the BACK side of the plastic plug.

I painted each hole pink here so it's clear there are 20 holes and you can see the expected-to-be-empty holes. I want you to verify the holes we expect to be empty are empty - that's the two at the end, and the two at the dead-center of the plug.

Next, I want you to verify EACH wire and its color match the same pattern shown here, from Crutchfield's documentation - be careful, if a single wire is shifted to be in the wrong place, that's a problem! The big concern order-wise is that the eight brown, white, and grey are correctly positioned:

​

Last but not least. Crutchfield should've sent you an email with "Installation instructions" after your purchase. That phrase should be in the title of the email, and the body look like what I'm pasting below, which they sent to me for my parent's Jeep I modernized recently.

​

If you click the "View Help Page" button I arrow'd, it should take you to all instructions for your install. If yours has a "VEIW YOUR WIRING GUIDE" link, can you print that to PDF or take a screencap and use the "UPLOAD A FILE" button in a reply window here to attach it? I'd like to review and make sure they're not telling you something different from what I know to be "reality":

​

Sample of what their wiring guides usually look like, they truly make it easy as shit for any skill level:

​

​

 

All the pins in my Metra harness line up with the Metra harness:

As far as my 9v battery. It definitely worked. I may or may not have tested it a few times for posterity sake. I even used getting a new one as an excuse to also grab a pack of beer in the same trip

 

Interestingly, I just put together that the “fabric seat” sticker on the amp doesn’t correspond to the leather interior I have.

 

You've got me stumped.

Based on what you just showed me, if you're wired like this, you should not have woofers. If you're wired like this, you should have woofers.

The wiring of your front doors is as follows, I'm using the passenger door as an example.

NOTE: The colors here aren't 100% accurate because I can't guarantee 2004, 2005 and 2006 double cab with JBL are all the same. ALSO the wires are highly unlikely to be identical coloring between doors, and I'm honestly strapped for time right now, so I can't dig into the EWD's to verify coloring and make special crappy little MS Paint images for each.

The gist of your JBL front door wiring, on both sides, is this:

• You have two basic plastic connectors for the speakers, with 4 wires each, shown boxed in orange here.
  • The upper one for the tweeters is pinned to the door about 8" below the tweeter itself
  • The lower one snaps into the 2-speaker housing in the lower door.
• There are two channels (two pairs of +/- wires) coming into the door, off the main door harness. As you see here, those two pairs of wires coming from the center of the door for your speakers are:
  • The 1st pair (yellow and grey here) is for the woofer, those two wires go directly to the 4-pin connector on the lower 2-speaker housing to feed the woofer, nothing weird about them.
  • The 2nd pair (green and blue here) go up to a 4-pin white connector pinned to door, where, as you'll see here, Toyota chose to use a loopback to populate the other holes, which then feeds down to the 2½" mid-high in the lower door (that's what the other two wires are in that lower 4-pin).

In case that 2nd pair is really confusing as to what it's doing, THIS IS WHAT IT LOOKS LIKE UP CLOSE (note I used different colors in that pic, sorry), and I'd recommend you read this for more background on how that little loopback thingy works, because it's bridging (parallel circuit) the tweeter and lower 2½" speaker to increase the load on the amp.​

​

​

 

So, what would I do, in your shoes, if you can't seem to get this wired right, but you know 100% the tweeters are working?

Well, the 2½" lower speaker isn't contributing a helluva lot to the overall system here. And I personally prefer using matched components, ideally ones that come with their own crossover, which typically only accept one pair of wires (+/-).

If it were me, and I didn't want to buy any adapters, I'd prefer something that's generally reversible later. So, if I were using component speakers, I would:

1. Untape to expose that little black/green loopback on the upper orange connector - it should be wrapped up in black tape from the factory.
2. Find the two short loopback wires after untaping, and cut that really short pair in the middle of their run as shown with the two red lines above the connector (or just de-pin from harness) BUT DO NOT CUT THE WIRES UP TO THE TWEETER (yet)
3. Cut the other two wires at the back of the tweeter (top red line), which you will repurpose for your crossover input
4. Unplug the lower orange connector/harness that feeds into the lower 2-speaker housing, and neatly bundle/tape up all of the harnesses/wires so there is only one pair to feed your crossover.
5. Mount your new speakers, and use the outputs off your component crossover to feed the new woofer and tweeter - you may need to finagle or drill a hole into the lower housing to wire up the new woofer, you may be able to repurpose the tweeter bracket if your new tweeter is center-mountable (as most JBL Club components are)
6. Crimp your Metra 8117 harness wires to your new head unit, at the dash, as shown HERE, which will force the radio to only use the yellow/green wires coming into the door.

​

 

Thank you @shifty` I definitely wouldn’t have been able to figure any of this out without you. I appreciate it. Probably gonna pull the trigger on some
Jbl club components from Crutchfield.

For my understanding’s sake, the purple and pink wires are the mid/tweeter channel coming off the head unit, and the green blue is the woofer channel from the head unit. I was trying to the woofer channel which for some reason didn’t work, probably a wiring snafu on my end. If I didnt run a component, theoretically I could use the purple and pink as positive and negative before it terminates in the connector going up to the tweeter. That connector is where it turns into a parallel circuit because of the little loopy do on the other side of the connector.

I really want to get a better understanding how circuits work. I’m starting to get it but the series vs parallel still confuses me a bit.

 

It confuses everyone until you work with it day in and day out for a while, or you study electrical engineering.

But this is the basic explanation with a picture. You see the parallel side of this picture, where the single positive wire forks out into two positive wires? Trace my door picture above, once the blue+green come into that connector with black/green wires. Notice one pair of black/green go up to the tweeter, while another pair split off that same feed, and loop pair loop to the other side of the connector to become the purple/pink pair down to the other speaker? Hopefully that makes sense. Any time you pair up positives and negatives, you effectively cut the impedance (ohms) of the speaker channel in half, which forces your amplifier to push harder. Which is great ... if your amp can handle lower impedances (not all can)

​

If you're referring to my picture above, "no" is the answer, you wouldn't use the purple/pink that runs between the jumpers. You would steel the initial feed up to the tweeter (maybe that's purple/pink on the door you're working on?)

Two important things to say here:

1. Nothing is going directly 'from the radio to the speakers', so if that idea is in your head, get it out. It's important to understand the path of wiring in your truck is Radio=>Amp=>Speakers. The radio is sending a low-level signal to the amp. The amp gets its signal and feeds that out to six channels, so six total +/- pairs of wires. Two speaker channels (four total wires) go to the driver front door to power 3 total speakers. Two speaker channels (four total wires) go to the passenger front door to power 3 total speakers. Then you have one channel each (two wires) going to each rear door to power one speaker per side. Six channels, a total of 12 wires going to the doors from your JBL amp. That's ultimately why Metra has you doubling up wires onto the Alpine's grey pair and white pair: You're needing to consolidate those two front channels by bonding the +/- wires together. Better yet, think about it like this: Your speakers are wired to your amp. All the amp bypass harness does is extend your door's speaker wiring up to your head unit, basically.
2. That means, in short, if we use my door picture as an example, the four "incoming" speaker wires, direct from the amp, are the blue+green pair feeding your highs, and yellow+grey pair feeding the woofer.

You CANNOT use the purple/pink pair! That green+black loopback pair will bite you in the ass if you try it.

If you really want to handle this the cheaper/less-reversible (but arguably easier) way, you'd:

• Cut the blue+green wire before it gets to the orange upper box, leaving maybe 2" of pigtail on that upper connector for reconnection later.
• Use that blue+green pair as your source for the crossover (those wires link to the white pair and gray pair on your Metra bypass harness, grey pair or white pair, depending which door you're working on)
• Leave the remaining factory wiring intact.
• If you do this it is CRITICAL you cap off these four wires in the Metra 8117 harness: White/red, Green/white, Brown/blue, Brown/yellow

That would look like this, although you obviously wouldn't keep the green/black wires attached to the tweeter or the woofer, and you'd tape down or remove any loose connectors you unplug.

And to be clear if you use the following image/setup, you would use THIS WIRING with your Metra harness, the wiring I just linked is ONLY IF you're using component speakers!

Please don't think any question is a dumb question, if this diagram doesn't make sense, ask the questions. :

​

 

Oops, sorry, I was referencing the wires on my truck when I said purple/pink wires. My bad. I should’ve clarified.


My door pink/purple wires are your drawing’s blue green.

Cool, I think I’m understanding this a little better.

Why would you use that only if using components?

 

Also, where do I send your case of beer to?

 

Yes, so purple/pink in your case for that door you're showing, but the other door may use different colors.

You want me to look in the 2005 DC wiring diagrams to tell you which is which (positive, negative), or can you just trace back from the tweeter? I think what's pink/purple on the driver side door will be blue/green on the passenger. I don't mind looking, it'll only take a sec.

As for "why that pair for components?", a couple of reasons:

1. Most importantly, it seems to be the only pair that's working with your current setup, for unknown reasons, so I would bail on using the woofer pair (grey/yellow in my door drawing above)
2. Components that use a crossover typically only require a single pair of wires, and you only have a single pair of "known good" wires
3. It just so happens that, on the Metra harness, they just so happened to use industry standard colors for the front driver door tweeter/2½" speaker's wires, as you see here - so everything will be plug-and-play-easy from a color-matching perspective, so it's super convenient THAT happens to be the pair that's working for your setup right now!
4. Make sense? If not, it's cool, ask any other questions you got, and LMK if you want me to tell you exactly which wires in the door are positive or negative.

​

 

Ya, if you don’t mind looking into which is positive and negative, that’d be awesome.

Did you mean that only a component speaker setup will work for this? A coaxial speaker would work too, correct?

 

THIS METRA 8117 WIRING will only work if you (1) use the two wires exactly at the location I'm mentioning, and (2) apply it in one of these three situations:

• BASIC: You're using a single-input crossover, like the ones that come with most mid+tweeter component systems, and using that OEM tweeter/mid wire pair to feed it.
• BASIC: You're using a single speaker (full-range/coaxial/triaxial/etc.), and using that OEM tweeter/mid wire pair to feed it
• ADVANCED: You're using multiple speakers and properly wiring them in either series or parallel or both (mixed) in such a way that the input uses that OEM tweeter/mid wire pair to feed the collection of speakers, and the impedance calculates out to around 4ohm

For your OEM door wiring colors ... I'm looking at the EWD and it shows:

On the drivers door, pink is (+) and purple is (-) for the tweeter/2.5" speaker
On the passenger door, light green is (+) and light blue is (-) for the tweeter/2.5" speaker

I have the worst time reading these damn things, I'm tempted to holler at @BubbaW to check my work here... Here's an overall shot and zoomed in shot of the 8spk JBL system (specifically for 2004 year)

​

CLOSEUP OF THAT:

​

 

Ok, so you have answered all my questions except where to send the beer.

Really, I appreciate all the help and the learning. And I’m sure there are countless lurkers on this site that will read this thread and be enabled or encouraged to turn some wrenches, twist some wires and break some 20 year old plastic door retainers because of you.