History of Problem:
1. After MH sat for about 6 weeks the Engine would not start and "Engine Communication Error" displayed on Dash.
2. Replaced 30 Amp Fuse in Rear Fuse panel and Engine Started about 5 times in a row.
3. Next Morning 30 amp Fuse Blown Again.
4. Investigated and found Battery + and - Pins burnt off at ECM Board. Also found that power to Engine Board is directly from Battery and not thru Ignition Solenoid. I believe this was so Solar can trickle charge Chassis battery but it also means power always on to ECM and VIM
5. Replaced ECM and transferred ECM wires (30 or so) to ECM Connector on Chassis wiring harness. I accidentally switch 1 of the 4 Battery +- Pairs and Fuse Blew. I switched wires to correct and fuse did not blow and MH Started.
6. Silverleaf on front 6 Pin Diagnostic plug does not display any Engine Parameter but the Front Dash Gauges work. I checked the front 6 Pin and rear 9 pin Deutsch Plugs with Engine Data Link Monitor and Rear rear Diagnostic Plug works and Front does not. Silverleaf works on Rear Diagnostic Plug also.
7. Coach is drive-able but have 1 ECM Warning on Dash (SPN 558 FMI 5) when Engine is at idle. As soon as I increase RPM the Warning clears and SPN 558 FMI 5 is gone.
8. 2 drive-able issues.
Jake Brake does not work on either High or Medium position. I believe the ECM believes that the Jake Brake is on. So therefore the coach jerks when I take off from a stop light with light accelerator pressure but if I am able to accelerate more firmly not jerk. I also believe that the ECM does not see from the front of J-1939 DL when I turn Jake Brake switch on or off.
Cruise Control turns on but unable to activate. The ECM does see that the Cruise Control is on or off.
9. Aladdin does not work for Engine Parameters.
10. Therefore, I decided I have a J 1939 data link problem. I performed a Multi-Meter J -1939 DL 60 Ohm Resistor and J -1939 wire check. The Resistor Check was good. There was J-1939 no ground or power shorts on Rear 9 Pin Diagnostic Pin. On the Front 6 Pin plug, I did not do a Resister check but the J-1939 wire check showed a short or ground on the J-1939 - wire.
So, therefore I am looking for any help on this. According to J-1939 trouble shooting steps, the next thing to do is to check for shorts or ground on the different J-1939 backbone segments. Also if anybody has had J-1939 problems, is their a service center that was able to resolve the J-1939 problem.
Thanks Dean
2006 HR Navigator 43 PDQ
DD60 Engine