Medium and Heavy Trucks
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Hi Josh, My name is***** will be glad to try to help. If the batteries test good, all the cables from the batteries to the starter check good and the connections are clean and tight including all grounds, All fuses and relays check good, have the ECM bench tested or try a test ECM to see if the problem resolves. Is the check engine light cycling with the key on as it should?
Are you getting any fault codes?
Hi Josh, I help on here part time in between jobs but we can post back and forth as needed. I will always reply back on my next available log in. When the scanner arrives check for any codes logged in the memory and let me know what they are. Could you confirm that there is no check engine light at all when the IGN is turned on? It should come on and then cycle off. If not the ECM is not communicating, lost power or ground, or faulty ECM. Let me know
If the ECM is not communicating, check the inline fuse between the battery box and engine ECM and that harness.
Sounds good. Pleasure to help
Thanks for the update.
Hi Josh, The ABS module is separate but is there is a short or a poor ground somewhere it can cause all kinds of odd things to happen including frying ECMs and modules, etc. What are the fault code numbers?
J1708 is a data link harness fault in the J1708 data link. Check the harness for corrosion, damaged connector pins, poor or broken grounds ( Battery to starter and chassis/frame), or damaged wiring. Look for any wires that may be rubbed through or shorted.
Click on this link for the schematics to help.