06 Silverado 1500, 4L60E

[surelyunsurebutitry]

Having problems finding the problem with my transmission, so far i have replaced PCM, checked/cleaned all grounds, continuity tested wiring from PCM to trans. Verified i have 12 volts w/key on at trans connector, ohm checked 1-2, 3-4, 3-2, TCC PWM and TCC pressure solenoid, all within specification. Codes i have are as follows.

PO740 TCC OPEN

PO753 SHIFT A

PO758 SHIFT B

PO785 SHIFT/TIMING 

P2761 TCC PRESS CONT OPEN

[Jsdirt]

9 times out of 10, multiple codes, no matter what system they're for, are due to bad wiring or connections. I'd find out what wires you're looking for, for the solenoids, and see if something has rubbed through somewhere, concentrating on areas of heat & vibration (loose sections of loom / harness, especially when curved around metal).

 

I had a bunch of similar codes with some network codes on my '07 900-series after a transmission swap. All that work, then had to deal with that b/s!! Was LIVID. Ended up being that huge round plug going into the trans case. Pins must not have made good contact when I plugged it in to the new transmission. Just some DeOxit D5 and a wiggle fixed it.