mtdave2

Speedo Not Working, Relationship To Abs, Cruise? Sharp Wiring Person N

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I put 1uzfe and trans from a 95 ls400 donor car. I used the lexus dash in the 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

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oh I guess i should say so it is clear. I have searched for the answer and there are many for the cable driven speedos. mine is all electric. not much i could find on that!

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Hi Dave and welcome.

I don't have an intelligent reply for you. Or a dumb answer for that matter.

One of the other members will chime in here, probably tomorrow. Also check "TIS.com" It is the lexus site for technical information.

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Thanks Paul, I hope someone will help. I'm worn out figuring everything out the hard way!

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For a speedometer, simply use a GPS. For the other thing, way over my head.

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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.

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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!

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