First gen Tacoma wiring

Hi
Ok so I am swapping a Tdi alh into a 2004 Toyota Tacoma and I bought a plug and play wiring harness from fast forward automotive and it’s a really nice harness I just need to hook up a couple wire to make it run

but my question is does anyone know or is really familiar with the wiring under the dash on these Tacomas because I need to tap into the vehicle speed sensor input side and the tach output side and I am having trouble finding the fire for them I bought a 2004 electric wiring diagram book but it’s not the easiest to read and fine the right wires


I also need to find on the back of the cluster the alternator excitor wire I found the battery light on the back of the cluster and there are two wires ones black with a white strip and ones light yellow and I think I need to tape into the yellow wire but I’m not 100 percent sure

Also when I remove the motor I remove the Toyota ecu and put my vw ecu in it’s place so I had to remove the wiring for the motor and when I did that I cut the wires that come from the transmission up to where it goes into the cab so I got the wires sorted and labeled now I just need a little help on finding out where there supposed to go back into the cab there are two connectors left that plugged into the Toyota ecu would those wires go back into some of those I just need help finding out what wires are what and where they need to be tied back into like the wires I need to get back into the cab are for the back up lights, vehicle speed sensor, 4wd actuator, tranny oil temp sensor, detection sw and I am not sure if that sensor or the 4wd position or the neutral position sensor, I also added a picture of the position of that last sensor if anyone’s knows that would be great appreciate

and this truck was a 6 cylinder truck with a manual transmission and it’s 4x4

 

I recently finished a 1KZ swap into my 2003 and it was my first time dealing with wiring and learned on the fly so I understand some of your frustration.

This is from the 2003 wiring diagram so it might be a little different.



The red/black wire is power to the speed sensor, green/red sends the signal to the speedo and blue goes to ground.

If your old engine was a 5VZ the green/black should be the tachometer signal coming from the igniter or if it was a 3RZ it would be the tach signal coming from the ECU. When I did my swap I moved this wire to a signal converter then ran another one back up to the cluster.

For the alternator the black/white wire is power to the light and the yellow goes to the alternator.



If I’m understanding this correctly you need to know what sensor is in the picture of the transfer case correct? If so that should be the 4WD detection switch and the low range detection switch should be on the other side (or the other way around.)

If your truck was originally equipped with a manual transmission it should have a Clutch Start Cancel switch rather than a neutral start switch.

 

@TnShooter

also another vw swap but pretty different model year within the 1st Gen which might make it of limited usefulness.

https://www.tacomaworld.com/threads/bimmertims-tacoma-build-tdi-swap-and-trip-reports.683473/

 

Yes it was a 6 cylinder truck manual and ok so it’s the detection sw 4wd so that sensor let it know when it’s in 4x4 or not and on the other side there is a oil temp sensor at the front on the tranny and then the next sensor back is the backup light switch I believe and then the last sensor on the right side is a vehicle speed sensor the transmission is actually form a 2002 toyta but that should make much of a difference other then it doesn’t have the 2-4 4wd switch on the t case that button on the shifter hand

 

If it’s the R150F transmission it shouldn’t have an oil temp sensor, I think that was only for the autos. These might help you a bit.

 

I'll try to get to this later tonight or tomorrow.
Family was in from out of town and they just left today.

I should have some free time here pretty soon to look at this.
Hang in their OP, I'll see if I can find some diagrams for you.

 

What transmission is in it now?

Also, the yellow wire for the alternator is only for the charge/battery light.
The alternator provides a ground when it fail. turning on the light letting you know it has failed. (is failing)