Rollendolan

I purchased the parts at Righetti Enterprises, a Cummins dealer in Stockton, CA. The people in their parts department are the most knowledgeable I have ever talked to. The company that works on multiplex, CCM, and J1939 is M & M Electronics in Ohio. I was told that the majority of the time that corrosion is either at the engine ECM or the rear diagnostic connector. Mike

I have resolved my problem. Thanks for everyone's input. The problem was a corroded J1939 wire and connector inside the female half of the ECM connector on the motor. Not an easy find. Attached is a picture of the pin and tools to remove the corroded pin. Thanks again. Mike

The ECM in the rear is on the passenger side. The motor home is in storage and I'll send you a picture of the connector when I go to the motor home. The triangular connector is a 3 pin connector -- yellow, green and bare wires. I have not found the one by the compressor. I am located in Northern California. Where are you located? Mike

All the connectors that I have found have what appears to be a shrink wrap on each end from the connector to the wire. None of them have electrical tape. I have unplugged the connector and everything appears to be okay -- nothing loose. Looks like the next connector from the rear ECM is going to the engine. I'll keep looking. Thanks, Mike

I found the connector on the right side. Also found the one going to the engine. I will keep searching. Do you have any other thoughts while I am searching? Thanks. Mike

I have checked in the arm rest area and don't see any wiring problems. I repaired the broken wire and it did not fix the problem. Do you have more info on this corroded connector next to the compressor? Is it a J1939 connector? Thank you for your help. Mike

I have not been able to fix the problem. I talked to Medallion and they believe it is a J1939 issue. I have been checking the connectors, front, center bay and rear. I just discovered the J1939 connector going to the transmission shift pad has a broken ground. I hope to repair that and see if that fixes it. Do you have any other thoughts? Thanks. Mike

Thank you very much for your responses. I will be looking into all of your suggestions and will let you know the outcome. Hopefully I will know something by monday afternoon. Mike D. 2008 signature

I own a 2008 Monaco Signature with 23,000 miles; Cummins 525 engine. On my last outing, I experienced the following problem: the check transmission light came on; then the check engine, ABS and ATC lights came on. Also, there were wild swings of the needles on the gauges and the window in the center of the dash read: "ENGINE COMM FAILURE". While all this took place, the engine ran normal, although the transmission locked out in 5th gear. The same problem exists now when you start the motor and let it idle. I have checked and all batteries are in good condition. Has anyone else experienced this problem or have any idea what it might be? Mike D - 2008 Signature