Engine/Transmission (1998.5 - 2002) PCM ?'s

[Bpostel]

Was wondering if anyone knows which wire running to the PCM supplies the power to it. I was driving down the road, tach started bouncing and quit altogether, cruise quit and AC also quit. This leads me to the PCM, swapped in another one and nothing. Anyone have any advice?

 

[dslmacdown]

I would try a crank sensor next

 

[trqmnstr]

I've read that when you have erratic tach readings and the truck jerks or quits, then the Crank Position Sensor is the culprit - but I'm no expert.

 

[Bpostel]

I just tried the cranksensor and still the same. If anyone knows which wire that supplies power to the PCM, please let me know, thanks.

 

[Bpostel]

Does anyone have a service manual that they can look this up for me.

 

[Marco]

Connector C-1



Cavity A2. LG/BK wire. Fused ignition Switch Input. ( Start- Run )



Cavity A22 RD/WT wire. Fused B+.



Cavity A31&A32 BK/TN wire. Ground.



Marco

 

[Bpostel]

Marco,

Thanks for the help. I switched PCM's and ECM's and still nothing. I went over the fuses, they looked ok. It must be something in the wiring harness. Do you have any other suggestions to try?

 

[Bpostel]

Well, I changed the wiring harness today and everything works again Oo.