AW4 resistor

lumpyidle · Dec 20, 2017

Hi everyone, can anybody tell me what the tcu resistor pack does? I've got an '89 Comanche that won't shift, and I discovered that it's broken and missing. Can this be the problem?

cruiser54 · Dec 20, 2017

lumpyidle said:
Hi everyone, can anybody tell me what the tcu resistor pack does? I've got an '89 Comanche that won't shift, and I discovered that it's broken and missing. Can this be the problem?

I wish I knew...

I can probably get the value of that resistor if needed though.

Are you getting power to the TCU? Is the fuse there?

lawsoncl · Dec 21, 2017

lumpyidle said:
Hi everyone, can anybody tell me what the tcu resistor pack does? I've got an '89 Comanche that won't shift, and I discovered that it's broken and missing. Can this be the problem?

The one in the wiring harness? It's a pull up resistor for the switch on the brake pedal that tells the t/c to unlock the torque converter. Shouldn't make it not shift at all. ** Edit http://www.naxja.org/forum/showthread.php?t=1053970 says it's a 1k resistor.

Can you define what "won't shift" means? Is it starting out in 1st and won't upshift, trying to start in 4th, skipping a gear, etc? You check the transmission fuse already?

lawsoncl · Dec 22, 2017

I saw your other post asking about a used 2wd AW4. What's the issue with yours? The AW4 is pretty reliable and most shifting problems are not mechanical. Often it's bad solenoids which can be replaced without dropping the tranny, bad throttle position sensor, throttle body cable not connected, or some other electrical issue.

If you pull the trans fuse, does it shift manually using the shifter?

cruiser54 · Dec 22, 2017

Listen to this guy^^.

BenWheelin · Dec 25, 2017

lawsoncl said:
I saw your other post asking about a used 2wd AW4. What's the issue with yours? The AW4 is pretty reliable and most shifting problems are not mechanical. Often it's bad solenoids which can be replaced without dropping the tranny, bad throttle position sensor, throttle body cable not connected, or some other electrical issue.

If you pull the trans fuse, does it shift manually using the shifter?

The way I read his post, the TCU is absent. As suggested, it should still shift manually with no electrical input. Unless it's making terminal sounds, it should be an easy fix.

AW4 resistor

lumpyidle

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cruiser54

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lawsoncl

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lawsoncl

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cruiser54

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BenWheelin

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