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 other shop that had me come in to check this 2013 chevy equinox 4 cylinder. they took the engine out to replace rear main seal. it won t crank or start.i tested power and grounds at pcm there all good .i have 2.7 volts at can high 2.23 on can low .but i have 120 ohms on pin 6 and 14 with battery disconnected i test conunication wires at pcm for short to ground they are good what am i missing
Post schematic? You tested can wires for short to ground?? 120 is not good. Check Can wires from dlc to ecm for an open I’m betting you’ll find an open or terminal issue at pcm connector
I believe you will have 120ohms if you are testing at a module that is still connected with a terminating resistor. What do you get between high and low at the dlc with the neg battery removed?
You have an open in the network somewhere. Probably upstream of the PCM, or the PCM itself. Between the DLC and the PCM are the EBCM (ABS), Power Steering Control Module and the Automatic Transmission assembly. All of those modules must be plugged in and working for communication to make it to the PCM.
Some or all of those connectors would have been unplugged during this job, so start with a careful visual inspection. I've got money on the EBCM connector not fully seated.
thanks for the help.i just figured it out.the customer has missed the pins and rammed the plug in on steering rack.straighten the pins plugged it back in started right up 60 ohms at dlc and communicating with modules now.thanks everyone
