hemi_fan

I have a 2001 LM7 Swap in a Volvo 240 with a stock PCM and 4L60e. It is throwing a lot of trans codes! I basically have a stock silverado harness plugged into the trans, PCM and fuse box. Any thoughts on where to start diagnosing all of these codes?

brandon6.0

iTrader: (32)

maybe a bad ground or no power to the trans wiring. Check pin E for 12v with key on.

U made the harness yourself or purchased a standalone harness? could also be a bad internal trans harness as well. Do u know if the trans work before u installed it?

hemi_fan

The harness is just a stock one modified per LT1swap.com

I do not know for sure that the trans wiring is all good but I am optimistic that it is ok. The guy I bought it from seemed like a straight shooter and had pulled it himself. I'll check for 12V.

brandon6.0

iTrader: (32)

yea check the 12v because without that the shift solenoids will not work and neither would the other solenoids.

hemi_fan

I checked the 12V and sure enough I had it wired wrong. I corrected it now BUT I am still getting all the codes. I have 12V on pin E now. Seems unlikely that all of the solenoid are simultaneously bad. The car shifts into "D" and drives but seems like it is just in 2nd gear all the time. Other thoughts?

hemi_fan

I noticed that the trans wiring is grounded to the Right Rear of the engine block per the wiring diagram. I'm now thinking that this is the issue. I also have a problem with the O2 sensor heater circuit. When I put the fuse in for this circuit it prevents the vehicle from starting/running (no fuel, PCM signal, etc.). It shares the same ground.

brandon6.0

iTrader: (32)

yea the o2 sensor circuit can cause weird issues.

rickpaw

This may sound dumb, but check to see that the trans plug is not plugged in backwards. I did this after the trans is installed, and got the exact same codes.