2001 Tundra SR5 Fuel Pump Wire Location?

Hey everyone!

First post here and happy to join the community. I am looking to put a kill switch in my Tundra, and I'm having a hard time locating it online. I am hoping there is a wire I can tap into inside the cab, and I am really hoping I don't need to go into the relay box under the hood and tap in from there.

Thanks

 

Anyone? Wondering if this type of question isn't allowed on this forum as there have been many views to this page...

 

Welcome....

I'll bring it back to the forefront in case it helps. While I have not seen many threads about kill switches on our first gens, I'm sure where there is a will there is a way.
The below PDF is the wiring diagram for 2001 if that will somewhat help. Many Electric Diagrams for various years can be found here---> Ultimate Wiring Diagrams Collection | Toyota Tundra Forum (tundras.com) thanks to @RainMan_PNW

2001 Tundra EWD - EWD429U

 

Yeah. Take what Bubba says and make it happen. Post up pics for a tutorial as this is something nobody here has done.

 

Pull down the manual that @BubbaW linked and search through the System Circuits. It will depend on what engine you have (there are different control diagrams based on each engine model - 2UZFE v8 or 5VZFE v6) and these older manuals actually include some system description information and trouble-shooting as well.

My best guess is that you will find there is a wire from the ECU (mounted in the passenger dash) that runts to the EFI relay coil and another that runs to the fuel pump relay coil. The load side of those relays are tied together, so killing either one of those would effectively disable the fuel pump from running.

 

I am simply spit balling for kicks and grins....what if one opens the gnd to fuel pump via Kill Switch for our 1st Gens ?

 

Thank you all so much for your input and information, I really appreciate it! I am going to try my best on Saturday to find that wire and hopefully I can figure it out and share with you all a step-by-step process. I will start with what RainMain_PNW said and look in the passenger dash, as well as study the diagrams that Bubba posted. I am very new to electrical diagrams and I am unsure how to read them and how they relate to where there are located in my truck, but I am going to give it my best. I will definitely update you all on my progress!

 

Can you elaborate on this a little more. I am trying to add a kill switch onto my 01 AC and I was actually surprised this wasn't a documented tutorial. I was watching Chris Fix's kill switch video and our cars are a little funnier cause the relays are in the engine bay and you can easily access the wires right behind the relay.

I used the wiring diagrams posted above to try and triangulate the cables that are on the back of the relay in the cab. I was pretty sure I found the cables I needed, but not of them tested 12v when the key was on. Check out my photos, am I crazy or do these wires correspond to the diagram?

I was thinking that the blue with orange stripe or black with blue stripe would definitely be my winner but no dice.

 

The gnd I mentioned a few years back is plausible but doing something at the driver kick panel with either the EFI or Fuel Pump relay would be a less wire run choice.

If more of the conductors were showing in the bigger connector, we might could tell more what it is and where it is.

If the 6 pin connector your showing with the B-L circled is located at driver kick panel, that should be 1A2 and if so the below pic should be accurate.

If by "key was on" you mean IGN ON only, there will be no 12vdc to fuel pump relay and that B-L wire you have circled. The fuel pump relay is only energized after truck has started and then the ECU sends the voltage to the fuel pump relay via the FPR output of ECU. In that state your technically at idle or light load, fuel pump is in low speed via the fuel pump resistor.

 

I was following this video: https://youtu.be/XUhXLsrZiE0?t=273
It starts at the section that I was copying with the whole "key was IGN ON only"

Does this not apply to a truck like ours? Yes the connector is at the kick panel, here is a more zoomed out photo:

 

That’s the smaller connector which I was showing in previous post. It’s the bigger connector we can’t see much of.

Haven’t watch video yet but to kind of answer your question concerning starting circuit. When we turn key to IGN ON, the EFI relay is only thing energized at that moment in tome. When we turn key to start, the starter cranks, ECU sees that STA signal along with crank/cam position signal, which energizes Circuit Open relay and lets current flow thru it’s now closed contacts to fuel pump via normally closed contacts of fuel pump relay.

 

I wish I had a better photo of that big wire clip but it's under the kick panel and it has a big black bar that you have to undo to unclip it.

Gotcha so I should be testing the blue and orange wire for 12v when I'm actually cranking the ignition.

 

Yes, the fuel pump has it's ground at pin 5 and is waiting for 12vdc at pin 4 to arrive.

As for the big connector, it took me a bit to find pin 13 to help confirm but since it is a bigger conductor size for AC motor and the color matches, L blue-R red. I feel fairly confident that bigger connector is 1A4.

Having said that and if you will confirm some of the other pin colors, I'd suggest also giving pin 26 Yellow, which feeds the COPN relay highlighted below with red arrow, as a choice.

The L/O for fuel pump relay contact pin 4 is not a bad choice, simply giving you an idea for 2 choices.

 

This is wonderfully helpful. You are so helpful! I would agree with you that this is definitely the 1A4 connector with all those colors matching up.

I will try cranking the engine today and testing those two color options. One last question... I was gonna go buy a switch today to install, how many amps do I need it to be?

 

In ChrisFix's video he uses this one: https://www.homedepot.com/p/Gardner-Bender-8-Amp-Single-Pole-Toggle-Switch-1-Pack-GSW-18/100141285

I like that it already has leads and it's form factor, but it's only 8 amp.

 

Since the EFI, COPN and Fuel Pump relay circuitry is protected with a 20 Amp fuse, I questioned why he felt an 8 amp switch would suffice, so I watched the video.

At the 2 minute mark he shows the switch which is 20 amp as seen in pic below. I also looked at the tools/parts list he mentioned and the link to the relay took me to Amazon concerning a.....
Nilight 90012E Heavy Duty Rocker Toggle 15A 250V 20A 125V SPST 2Pin ON/Off Switch

$8 Nilight 90012E Heavy Duty Rocker Toggle 15A 250V 20A 125V SPST 2Pin ON/Off Switch Metal Bat Waterproof Boot Cap Cover-5 Pack, 2 Years Warranty

Amazon.com: Nilight 90012E Heavy Duty Rocker Toggle 15A 250V 20A 125V SPST 2Pin ON/Off Switch Metal Bat Waterproof Boot Cap Cover-5 Pack, 2 Years Warranty : Automotive




I'll stick to what I was going to recommend which would be a 20-25 amp SPST switch with at least 16 gauge wire.

 

Very nice attention to detail on that one. I bought a 20amp switch and am getting back to business on this.

I have the 1A4 plug detached and I was gonna check the cranking voltage but the car doesn't crank. I am assuming a lot of these wires need to be plugged in to do that.

Am I safe to assume that if I cut my switch into the Blue and Orange wire (L-O) that it'll do what I need to do. Thought I would test the cranking voltage to make sure that's my chosen wire.

 

Also @BubbaW I like the yellow wire to the COPN relay because it's just one wire into the plug vs the blue and orange wire which has two. If I disable the COPN cable would the car still crank?

In my head it would be nice to have the car crank but not start to make a thief nervous and give up.

 

For sure....won't look them all up again since you have the 2001 EWD but I'll list a few important ones....

Pin
24 - Pink....gnd for starter relay @ it's pin 2
26 - Yellow....gnd for C/OPN relay @ it's pin 2

That should be enough

My answer would be, if you cut the Blue and Orange wire (L-O), the Fuel Pump will never receive the 12vdc it needs.

What I would do personally and always try to do before cutting that wire or any wire is to always double check that I am definitely on the right wire by checking for continuity from point A to point B.

You have the meter for it, so pull the Fuel Pump relay and unplug connector 1A4. You'll probably need an extra length of jumper wire but put meter on resistance and check for continuity from pin 4 of Fuel Pump relay to pin 5 Eng bay side of connector 1A4. If you have a dead short, you're cookin and on right conductor.

One other comment/question....if you do choose the L-O wire, the drawing shows pin 4 and pin 5 from Fuel Pump relay is doubled up at connector 1A4 pin 5, is that true ?
If true, I would consider cutting on opposite side of connector where there's only 1 conductor.



It's April Fools but I aint gonna play one. Cut at your own risk !

 

Sorry, didn’t catch that you did another post.

Yes, truck will crank but the fuel pump will not operate.

You can test that by pulling the C/OPN relay in Eng bay. and see the reaction. The fuel pump relay will then not have 12vdc going thru its normally closed contacts 3 and 4 to feed 12vdc to fuel pump during initial start sequence. As long as key is held in start position, starter will grind

 

..

 

Got it all wired up and it's working great! I took some pictures and found an AWESOME spot to mount the switch, so I will get those together for a little mini-tutorial.

 

...and ye ole' thief will be waiting for the pics