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Hi,
I have a 01 caravan 3.3 auto that i had on ramps to fix coolant leak.
I ended up bypassing rear heater core. But we had a freeze -20. before i started it again.
When I started it (30 degrees air temp) the speedo went wacko and shifter indicator was all lit.
It died few times when i put it in reverse.
I drove it a block while it was trying to figure out what gear to be in until i parked it.
Next day it started up, speedo jumped then settled at 0.
Now speedo stays at zero. trans stuck in limp mode and drives.
I tested battery, wiggled wires. no corrosion at pcm. speed sensor wires look good.
Has code P1698 pcm is not receiving a bus message from the tcm.
erased code and it came back.
How do i test for broken wires. Bad module. Or is something else causing module to go quite.
I have multi meter and cheap basic scan tool. Can I test speedos resistance from tcm plug?
Schematics for tcm, ecm and any others i'll need.
Note air bag light is on, I don't know if it was before. I read somewhere that air bag module can disrupt bus signal. Can I just unplug module to test if tcm communicates again.
Those vans....those vans...it wouldn’t be polite to say what I want here. My neighbors have two, 01’ 03’. I changed a abs sensor on the 03’ and it whacked the tranny out. You have to go in the tcm with a scan tool and do reset procedure. It’s pretty simple but does need a tool. I’m not aware of another way. My old otc genisys handled it no problem.
There’s also the possibility that little silver box on the front of the fuse box has some corrosion. If you have other whacky electrical gremlins take that box apart and clean well
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