Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
I have a no crank no start issue, the pintle on my on gear display isn't illuminated so my vehicle isn't reading its in park. This vehicle has a new TCM and Fuse-block, the previous time the fuse block was the issue with the same concern but now it has returned with the same issue. Measured resistance at DLC connector, got 120 ohms for my High speed GMLAN network. Schematic shows internally built 120 ohm resistor in ECM and separate 120 Ohm resistor. Disconnected ECM to isolate circuit, measured resistance at DLC and still had resistance 120 ohms. This isolates my problem to the ECM leg. Tried new ECM but problem still exists. Measured terminals in ECM that contain resistor and have 120 ohms in ECM. Measured Power and ground at TCM, EBCM, Parking Assist control module and resistance between each module in that circuit leg. All measurements good. But have no communication with ECM,TCM,EBCM,Headlamp Control module, FPCM, park assist control module.
have you checked the actual communication wires to the pcm for an open? id be half tempted to check it at x165 pins 12 and 11. then look for 120 ohms. if you get it id move upstream from there on the schematic
