I could use some help. I'm trying to get my guys truck running. His truck through a CAT code. we took a small trip to see family for easter. On the way home we started having issues. Now it won't start. Has new battery and new starter. When I turn the key, it acts like it wants to engage but doesn't. Put a scanner on it. It says ECM. I have never had any problems with these in the past. Will this cause these issues? I'm at my wits end trying to figure this out and its taking a toll on my bank acct. Would love some input on anything else to check before buying another ECM. Thanks!

 

Have you physically checked ALL of your Ground conductors / connections and Fuses and Relays / Relay sockets and stabs ?

99.5 % of mysterious electrical issues can be attributed to bad connections from vibration , Corrosion or Overloading / short circuiting .

Did you try removing the Negative battery cable from the battery for 1 Hour to allow any capacitive charges to dissipate from coils and capacitors ? Then reconnect the Negative battery cable to see if any changes occurred ?

I have an ‘07 Silverado and when mine did this I found 3 corroded in half but visibly NON blown fuses that failed a continuity test .
I also had issues with corrosion on those fuse stabs and sockets as well as several of the Relay stabs and sockets in the under hood fuse panel .

Long story short . Your time is far less expensive than the “Parts Cannon”