2013 Tundra no battery light. charging system faulty

Hey, I warned you the first SCHEMATICS were NOT for this vehicle and that you need to track down the applicable fuses. Take away, they are similar but not the same and fuses need pulled, not just looked at. To fix this you have to do the work and take the plug out of the alternator as Jeff said.

If you don't want to buy a meter, get a 12V incandescent test lamp as was mentioned before and in 5 minutes you could have some facts with a simple test light following what was written here about unplugging the connector.

The battery (B), Sense (S), and Ignition (IG) all need power. A test lamp will show this. I suspect the ECM (M) will also show some voltage with key on but I've never tested it. If one of the first three is not powered you begin the trace to find the break in the connection back to the origin which can also be done with a test lamp.

O/T
My observation is many have had bad luck and bizarre electrical issues from using cheap reman alternators. If going reman get Denso! Not that I'm saying the problem is the Alt.

 

I would agree with most on here.... We can guess till we're blue in the face, but you will have to pull panels and test that wiring, there is no way around it. You may get lucky and it's in plain view, or it may be losing contact behind the instrument panel. If all else is good, wiring is the culprit.

 

Ok then, if I’m testing the IG grn/yellow wire , should I have the 4 pin connector (A9 terminal) plug in at the alternator or unplug w key on, also is it with light tester or voltage meter? Yes, the turn signal problem (didn’t work) started days prior to the charging went dead too. It started with turn signal not operating then no charge with cluster led (battery light) out. With key on , no turn signal. The repair shop didn’t had solution why turn signal didn’t work in first place. That time charging system work , later day, it’s charging system gone dead too. New battery , new alternator (exchange 2x), and fuses good as well. Now I’m looking at the certain wires and battery light . Your info may help me here. Thx . I’ll let you know what my next findings will be. I’ll test the wires today. What wires? Now I know which one , thx. Oh one more thing, when I’m testing the LH-IG 7.5 fuse socket , do I have to leave the fuse in the socket or take it out to test the socket seats? Am I using the grd connection there too as well for testing ?

 

If the turn signals are not working replace the fuse. The fuse being bad will kill the turn signals and charging from the alternator. Put a brand new fuse in it not matter if the old one looks/test good and report back.

If it still doesn’t work we can go to testing wires.

With a new fuse and blinkers working it should be charging.

 

Does this mean I have to take the vehicle part at dash (combination meter) cluster to indicator? Is indicator you mentioned battery LED?

 

As I have mentioned replacing the 7.5A LH-IG fuse should be the first thing you do and here is why:

As the key is turned to ON, the ignition switch powers several relays in the body control module. One of these is the IG No.1 Relay. When this relay closes (the key comes ON) it provides 12v+ power to the 7.5A LH-IG fuse.



If we go back to looking at the charging circuit you will see this same 7.5A LH-IG fuse. Basically as the key comes ON power goes through this fuse into the alternator to "wake up" and "turn on" the IC Regulator chip. As I have said before if this power signal never comes in, the alternator will never start charging and the light on the dash will never work. Taking apart the cluster right now would be a waste of time.





BUT wait there is more, this same fuse 7.5A LH-IG powers the flasher relay and blinkers. It works the same way as above for the alternator. The key comes on, power is passed through the fuse to the Flasher Relay to "wake up"/ tell it the truck is running.


The fact that your truck is not charging and that the blinkers are not working means their is an issue around this fuse most likely. This is where the break is not allowing the power signal to reach the alternator or flasher relay. You don't realize it yet but as soon as your blinkers quit working the truck also quit charging, it just took you a few days to notice the battery dead after the blinkers no longer worked.

Remove and replace the 7.5 LH-IG fuse with a brand new one. Trust me on this, I don’t care how good the fuse looks put a new one in. If you have checked with a voltmeter to see power is coming in on one side, yet none of these things are working its because the inside of the fuse is bad and not passing the power through.

The fuse is in the interior fuse box under the dash.

 

Thank you, I’m still getting to vehicle . I’ll report back to you today on my findings. For now , I got two questions: 1. I’m thinking to test the 4 pins at alternator connector , while testing should all pins lite w tester Or just IG lite, When key turn-on? I’ll be close to 4 pins connector working w IG wire testing today. 2. You mention LH-IG 7.5A ; is there two fuses of that? I know I found one under the dash (driver side) , is there one more ? If so, where?

 

1) The 4 Pin connector at the alternator (E9). You can test with volt meter or test light (Obviously 12V hot makes the test light lite up)
Pin 1 (S) Black/Yellow should be hot 12v all the time. It is wired directly to the battery
Pin 2 (IG) Green/Yellow should be hot 12v with the Key ON.... This is the important one to test. I suspect you are not getting 12V when the key comes on here which is your problem.
Pin 3 (M) Red I think will be 12v with the Key ON also. It is a signal wire the ECM
Pin 4 (L) Black should be hot 12v (not sure if key on/off matters here) when this wire is taken low to ground it turns on the light on the cluster.





2) There is only one 7.5A LH-IG fuse and it is in the interior fuse box under the dash.

3)"I’ll be close to 4 pins connector working w IG wire testing today" Does the truck have other ingition wire problems? This could play a factor in the issue of no blinkers or charging also.

 

3) no other ignition wire problems. I meant I’ll be working on LH-IG 7.5 fuse wiring continuity today.
As of right now I just light test the green/yellow pin 2 .With key on , pin 2 didnt lite.
Pin 1 lite w key off/ on. Pin 3. &4 did not lite w key off/on.
Now I’m testing the pin 2 wire to LH-IG 7.5 fuse for break.

 

Did you replace the fuse and then test again. A bad fuse will cause you to not get 12v at pin 2 no matter what. I know I have said replace the fuse with a new one 10x and I mean it because on more than one occasion I have seen what looked like a good fuse to be the problem with the charging circuit. Do yourself a favor and put a new one in it before you do anything else to save you the headache.

 

Hey Jeff, what service are you using to pull schematics from if you don't mind me asking?

I ask as I plan to create a hybrid flasher relay module using a Diode Dynamics one tap flasher module and integrate into our trucks (crazy) flasher module making the truck, LED compatible. I bought spare modules for our truck and some connectors, a part of a harness, etc. The next step is to breadboard OEM module, then replace that with hybrid programmable module and make sure nothing lets smoke out. I've been meaning to start a new thread but haven't seen many here do a deep dive on electronics. I've got my proposed pin mapping laid out but haven't done the breadboard test yet. After breadboard test, that flasher module will have components pulled off. Future state is plug and play to the truck with custom built PCB. Then see if anyone wants them... There seems to be a market.

Thanks

 

They all come from the TIS (Toyota Information System) but all the wiring diagrams are available here on the forum https://www.tundras.com/threads/ultimate-tundra-wiring-diagrams-collection.81448/

You idea seems easy enough, probably pretty simple. I assume it would be programmable to set flash speed, sound ect.

EDIT: just watched a video on it. The unlock and lock features are pretty cool. A simple 6in pigtail wire harness could easily make this plug and play. Im on board to help build if you need.

 

I got new LH-IG 7.5A fuse put in, no changes. Same. I test light the 4 pins. I disconnect the male /female terminal (AE1) by main fuse box , ran a jumper wire from the E9 (alternator ) connector to battery and test light each 4 pins to (AE1) male #1,2’,3 &4 wire . #2 (grn/yell) wire didnt light up. I jump the (AE1) female (#2 ) pink wire to positive battery (with battery cable off) then hook the light tester at LH-IG 7.5 socket (w fuse out) and tester to grd, it lite. So the pink wire is good . I went back to connector (AE1) male #2 (grn/yell wire) and by pass w jumper wire to (E9 ) connector #2 at alternator 4 pins . And reconnect E9 into alternator . I turn on the ignition key . The battery light came on ! Yay. I start the engine . Battery charging gauge went to 13 volt. Ran for 25 mins the gauge start to go down a lil but when I accelerate the gas panel , needle goes up and depress gas panel , needle goes down to 11 colts and stays there. Something still wrong . It charging but needle stays at 11 volts. The diagnostic the engine light reader , it read brake sensor and high / low voltage charging reading . Abs/skid light is on w engine running. The turn signal light is on in rear (good) but the front. Sun went down in me.

 

When it is running and charging did you check the battery with a voltmeter? Should be 13-14v. The dash gauge is not the best for accuracy.

Did you test light both side of the fuse without the jumper? I think your jumper is back feeding to power the blinkers now.

Do you have an actual voltmeter with continuity setting?

Also is there anything else in the truck not working? Any little thing you can think of?

 

The jumper is acting like #2 grn/yell now for temporary fix for now. The original #2 grn/yell is cut off both ends where jumper is attached at E9 #2 go over the engine on to connector AE1 grn/yell wire (next to main fuse box). Yes, the ABS and Skid light are on when engine e running. The charge ran great til 15 mins , engine slow down a bit then battery gauge at cluster started to head low voltage,,, it reached 11 volt and it stayed there. When I accelerate the gas paddle the battery gauge goes up to 13 volts. Release Gas paddle it goes back down to 11 volts at battery gauge. No , I didn’t test w voltage meter at battery. I just went w what the engine is doing and battery gauge. Again abs and skid light is on when engine running .diagnostics code came up w low/ hi voltage and code for brake sensor. So there is 2 codes detected. I’ll post that later of the codes.

 

I understand what you did with the jumper, the problem is with a break on the green/yellow wire the jumper would fix it. However the blinkers should have worked without the jumper if a broken green/yellow was the only problem.

The fact the blinkers started working with the jumper wire means you still have problems with the 7.5A fuse. The jumper wire is now back feeding power to the fuse and making the blinkers work. This is not right.

Are you absolutely sure you replaced and have been checking the right 7.5A fuse in the interior fuse box? There are several of them in there. It has to be the one in this spot highlighted in red.


Something is still wrong around this fuse. I have seen it being blown and replacing it fix the exact issues you are having multiple times. No surprise but if you are not replacing or checking the right fuse you will never figure this out. Have to be sure you are looking at the right one.


As far as the ABS codes it’s nothing to worry about. The fault you mentioned is the ABS throwing a code because voltage dropped to low when the truck quit charging. Fix the fuse issue, clear the code and your good.




The absolute next thing I would do would be to unhook the jumper you added. Then get your test light and check both sides of the 7.5A fuse under the dash. You can leave the fuse plugged in. Put the probe of the test light on each of the little square holes on the face of the fuse. One on each side of the 7.5 lettering. You can see the shiny metal inside each of the little holes. These connector to the spades of the fuse.

With the key off and no jumper wire the test light should NOT light on both sides of the fuse. When you turn the key on the light should light on both sides of the fuse.

 

Again

I install a new LH-IG 7.5A before I ran a jumper . As soon as I installed, I test light key off (no light) and then on , light came on. I also test light the socket without the fuse in the socket seat , no light w key off. I turn the key on, The light came on, on fire wall side of the socket seat, and no light on the other end socket seat. Later, I test the grn/yell #2 at 4 pin (E9) to other end at connector AE1 (I unhooked) there I found out that #2 grn/yell didn’t light but the other 3 pins lite. That is why I jumped the grn/yell #2 wire. The battery light came back on (ever before) when I turn key on, then started the motor. Immediately the charging gauge at cluster needle race to 13 volts. It stayed there for 15 mins then it trigger something , motor slowed down a slight in lil rough mode and charge cluster needle start to come down to 11 volts. I put on gas at paddle , needle goes back up to13 volts then foot off the gas comes back then to 11 volts. The skid control wire has a tear at the wheel and one other wire believe to be headlight or turn signal wire torn down ward by a neighbor puppy . Those wires I’m going replace then go back to #2 grn/yell wire (jumper) start working on it again soon. Yes, The LH-IG 7.5A is correct fuse and socket location is legit point I replace u set under dash fuse box.

 

This is all good info and now proves the fuse and good and working right according to what you report.

I would take the test light and check the pin 5 pink wire at the AJ1 connector. If it lights with the key on you know you wiring up to there is good. Then you can focus on the green/yellow from AJ1 to the E9 alternator pin. This seems like where your break in the wire will be if you have one.

Getting closer to figuring this out.

Do the blinkers now work without the jumper wire installed? They should

 

The blinker also battery light start to work after I put jumper at #2 grn/yell wire but only the rear turn signal work to blink , not the front. Blinker is flashing faster then normal at rear turn signal. I’ll check AJ1 connector when I replace puppy damaged skid and headlight harness . I’m at auto store looking into harness now.

 

I find that hard to believe. If the fuse is good which you said it was the blinkers should work without the jumper wire.

After the fuse the power is separated into 3 different circuits. One for the blinkers one for charging and another one.

If hooking up the jumper is the only way to get the blinkers to work you still have a problem at the fuse. Simple as that.

I feel like we are just going in circles here. You said you tested the fuse without the jumper wire and both sides lite the test light. If this is true the blinkers should have been working

 

Perhaps behind that fuse panel needs an inspection? Maybe burned, broken, chewed off?

Disconnect battery before removing!

 

That’s when I disconnect the AE1 and tested the pink wire to (w battery not hook up but jump from positive battery to pink wire at AE1 then went under the dash to LH-IG 7.5A fuse pull out and tested the socket seat away from the wall , it lite (without the battery on nor key in) just jump test the pink wire. It lite. That’s why I went back to #2 grn/yellow where I jumped light test earlier which it didn’t lite. So I jumped a wire from E9 #2 grn/yell to AE1. I put the battery cable back on and turn the key and battery light came on. And start the vehicle . That’s part I said fuse lite at LH-IG 7.5A . Way before anything else , I did test light same fuse with battery cables on and key on … that’s where the LH-IG 7.5A (fire wall side lite). So there two things I did w LH-IG 7.5A for testing. I know that part is good. Remember I track it down to #2 grn/yell wire (break) between E9 and AE1 ,,, that’s where I jumped w a wire and battery cables on and I turn the key and battery light came on finally. I started the engine , first it charge at good 13 volts then after 15 mins it started to go to 11 at charging gauge cluster. I suspect it’s the wires that the puppy chewed on and pulled at two place . That’s the parts I order today . Which is skid sensor wire and light wire connector till then I should be able to know ,, it might go good after I install the new skid sensor wire . We shall see.oh it throw a C1330 plus C1241 diagnostic reading. Both pointing to skid.

 

Nope. Pink wire from AE1 to fuse panel (under dash) to fuse LH-IG 7.5A check out ok w test light w battery unhook but jumped just for a test. Continuity is good on the pink wire.

 

Where is AJ1 located at? On the book its states under the passenger dash . Is that correct?

 

Sorry AE1 not AJ1… the one you have been looking at

 

Ok. I install new skid sensor on passenger side wheel ( where the puppy rip out). I turn on the key ( abs and skid light) lite and went off as soon as I started the engine . Solve the abs and skid light. But charging went good then started to go down again at cluster gauge . Then I went back to #2 grn/yell wire jumper, undid the jumper to a regular small size wire , this time I bypass it from #2 (E9) grn/wire to AE1. I re started the engine. I put volt meter (#2 grn/yell bypass wire) at AE1 , it read 13.88. I hook the old cut #2 grn/ yell w alligator clip wire to bypas. No difference stayed at 13.88 volt . Diagnostic reading code I erase. Never came back on except P1605 (I’ll post screen shot here). All the light off at cluster except door ajar and seat belt light on. The truck charging good . Yay !!!! I test drive it in town. Good. My finding is engine number 2 wire ( alternator /starter harness ) #2 grn/yell break . I bypass it . Now back to normal.

 

Nice to hear it is fixed and back to normal.

As I had mentioned all along not providing key on ignition power to the alternator is a common problem on these trucks and will keep them from charging.


Just to add to this:
The green/yellow wire could have broken and if it grounded (shorted out) it would have blow the fuse also.

The bad fuse is the only way to get no charge and no blinkers. Had the green/yellow wire broken and the fuse remained good the blinkers would have never quit working.

Doesn’t really matter now since it’s all fixed but I post this for the next guy who might read this one day.

Also worth noting the replacement of the wheel speed sensor and wiring where the puppy damaged it most likely had nothing to do with the charging issue.

You fixed two separate problems at the same time

 

Ok. I install new skid sensor on passenger side wheel ( where the puppy rip out). I turn on the key ( abs and skid light) lite and went off as soon as I started the engine . Solve the abs and skid light. But charging went good then started to go down again at cluster gauge . Then I went back to #2 grn/yell wire jumper, undid the jumper to a regular small size wire , this time I bypass it from #2 (E9) grn/wire to AE1. I re started the engine. I put volt meter (#2 grn/yell bypass wire) at AE1 , it read 13.88. I hook the old cut #2 grn/ yell w w alternator clip wire to bypas. No difference stayed at 13.88 volt . Diagnostic reading code I erase. Never came back on except P1605 (I’ll post screen shot here). All the light off at cluster except door ajar and seat belt light on. The truck charging good . Yay !!!! I test drive it in town. Good. My finding is engine number 2 wire ( alternator /starter harness ) #2 grn/yell break. I bypass it . Now back to normal.

 

I guess this diagnostic C1605 is just a matter of buying a bottle of mass air flow And clean.