Beefdoc

Here's the story: 2 weeks ago truck dies like shut of key while driving in town. Pulled to mechanic, figured another injector pump shot. Nope, technician finds fuse #9 blown, replaces, truck runs, no problem, checked wiring and could not find short. Thought maybe fuse got weak after 435k miles. Fuse 9 apparently just powers up PCM and cummins controller.

Last week, truck was running/working fine, parked for 2 days had quarter of inch rain on it, went to start it no go, fuse blown. Put in 2 more fuses, still blew immediatly (big spark) when ignition key is turned on. Came back to truck 6hrs later tried another fuse and away we went, worked fine.

Drove truck 250miles that day, no issues. Parked it and had a half inch of rain on it. Tried to start it 2 days later, fuse blows immediately when ignition key is turned on. It is a DEAD short, get good sparkage when it blows. Have talked to mechanic about rewiring power to the PCM and Cummins controller, but do not have a way to get truck to him yet (do it myself if I knew which wires were power wireds). Thought I would drop a line on here and see if anyone has a good idea where to start looking for this short. Currently fuse still blows and truck will not function.

Thanks for your time
Matt

AggieJustin

Here's the path of that circuit from the Junction Block all the way to the connectors on the ECM and PCM. Hopefully it will help find a connection that is corroded.

The output of Fuse #9 goes to Connector C1-pin#10 on the back of the Junction Block. The wire for the circuit is Light Green with a Black tracer.



At splice S107. I'm not sure if this splice will be there or not, since this is a splice to feed the Fuel Pump Relay in the PDC for a gas engine.



At splice S171. This is the splice that splits the feed to the ECM and PCM.



At connectors C125-pin #1 (on the ECM), C130-pin #28 (on the PDC) and C1-pin #2 (on the PCM)