so recently i discovered that my VSS was disabling my car from starting. i checked the pinout, and saw that it shared the same power feed and ground wire that CKP and CMP uses. I did a continuity test on the VSS connector's orange and bl/lb (power and ground) wires, and there was no short. pulled the sensor, and the pins showed no short with the same test. am i looking for a specific resistance 'window'? my FSM is surprisingly lacking (pdf version).

side note, i learned that it's impossible to simply swap PCM's. each one is programmed with the car's VIN, necessitating reprogramming, regardless if the basic things match up, and this information came from the local dodge dealer. very interesting to learn, as ive never come across this, though ive always owned older cars.

 

um, no Codes?
btw, VSS as in Vehicle speed sensor?

 

Yes. It shorts out VREF.

 

No, no codes.

Vref? I'm not familiar with that, can you elaborate on definition and function?

 

It's a 5V reference signal the PCM sends to the sensors on basically 1 wire. If the sensor internally shorts it brings the Reference voltage down and the computer doesn't know what to do.

 

ahhh ok. i realized earlier that if it runs with it unplugged, it must not be my wiring..so i will operate on the sound presumption of it being my VSS and mismatched PCM as to why my car isnt running. look forward to my new pcm to see if i can get her running normally!

 

New PCM arrived this morning. Purposely put it off thanks to waning what if's in my head. After it cooled down a bit (here in north texas, it will reach 102 during peak hours) I got out there around 7pm, plugged the PCM in, and reluctantly turned the key. SHE LIVES! So the new PCM is a success, and I still just need a new VSS. Next is the drive test to verify the transmission I overhauled is error free....*nervous*