Engine/Transmission (1998.5 - 2002) What do these codes mean?

[AKDrifter]

My truck has had a some computer problems recently and the dealership showed me these codes:



P0645

P1694

P1693



They could'nt work on the rig because the fan was not on, I'm sending it down to Juneau today



Is there anything about these codes I should know before they diagnose and fix the truck?



Paul

 

[WadePatton]

Originally posted by AKDrifter

My truck has had a some computer problems recently and the dealership showed me these codes:

P0645

P1694

P1693

They could'nt work on the rig because the fan was not on, I'm sending it down to Juneau today.

That makes perfect sense. No fan, no workie. :-{}

And hey pal, here's some codes.



P1693 means that a companion code was set in the PCM/ECM. no big deal-generic code that says "there's a code".



P1694 "Fault In Companion Module" "No CCD/J1850 messages received from the powertrain control module-Aisin transmission"



P0645 "A/C Clutch Relay Circuit" "An open or shorted condition detected in the A/C clutch relay control circuit. "



"CCD" refers to the in/out circuits of the ECM/PCM. Further reading indicates that the main function of "CCD bus circuits" is to control instrument panel stuff.



Info from 2000 service manual.