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!
Though my scanner has a battery reset, unfortunatelys it does not support one for Cadillac or any GM model. Is there another way of resetting battery after a replacement was done? The cars starting fine exept the headlamps and signal lights dont work after battery replacemen; there are no other issues nor DTC...thank you.
Like wise the terminating resistor read 62 ohms with X3 connector unplug and 122.7 plugged in.
I am not versed in CAN Bus. But does the waveform indicate short to ground in the CAN Lo? I checked power to all connectors and all read battery voltage. It was only the ground wire in connextor X3 that read 29.6 mv KOEO and 31.4 mv KOER. In the absence of a wiring diagram, I cannot trace wires thats connected to connector X3.
I hope someone out there can share his thoughts or expertise. I want to make sure if its a component or module that is defective. Thanks
In reality they both look wrong. You are supposed to see 2.5 yo 3.5 volts on can h and 2.5 to 1.5 can l. You sure you have a good scope ground?? If they looked like that then I’d suspect a no communication with the bus.
I have tried other modules yet...I just finishede checking the integrated power/fuse and relay box and noticed that the two bolts holding the main connectors was loose, hmmm just wondering if can be a cause
The owner couldnt wait any longer and believes that it is the BCM that is faulty. Despite my telling him my intial tests showed otherwise, he took the car and bought a new BCM. A week later he called to ask if I can look at it again as the problem did not go away. This time I had to refuse and advise him to bring it to another shop instead.
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