lexus v8 and dash in toyota. speedo issue. need sharp wiring guy.

[mtdave2]

I put 1uzfe and trans from a 95 ls400 donor car. I used the lexus dash in the 92 Toyota. I have it running and almost all is well. The speedo is not working and I am trying to understand the circuit to make this thing work!

The speedo does not work nor does the trip meter (nor does the torque converter. So the whole system is dead. I used an uncut loom and the 2 wire speed seniors (two of them) are wired through a plug I didn’t have to touch. The only wiring I did was to connect the output from the engine ecu (spdm) to the dash wire for the speedo.

My question is how the abs system and the wheel speed sensors play into this. I know they must and is probably why my speedo is not working. Though I have not seen any wiring diagram that really shows how this all works. Exactly which wire from the abs to the ecu sends info to which pin on the ecu, at what pulse rate? I dont have wheel sensors, so how i can fool this thing!

Any help would be greatly appreciated

 

[mtdave2]

so far I have established that the ecu is getting pulses from both speed sensors on the trany. still no output from the ecu to the spdm pin. no lock up on od either. this model does not have an od button, it does it all automatically.

 

[mtdave2]

interesting turn. I found that the spdm wire have voltage in it coming FROM the dash TO the wire. ugh

 

[BoatRacer]

I wish I could be of help to you, but I appreciate your replies. I hope to do a similar swap at some point and this could help out.

 

[mtdave2]

if anyone cares, there was interment connection in one of the wires going to the speed sensor. I ended up just running two new wires and I had an extra plug. wired it up and it worked! I had tested that circuit several times and it was always good. one more time because i had checked everything else, and I found the issue. what a pain!