A follow-up to the previous post re. Diagnosis.....
Diagnosis from large rv dealer in texas was completely wrong !!!!
I took the coach to Cummins Western Canada branch in Winnipeg where they determined that the code 13 meant low/no voltage. From the service department:
"Test run - shutting down on code 13. Perform troubleshooting. Excitation field not energizing. Check excitation wiring. Remove panelling from generator. Remove intake assembly. Check brushes - wiring on brush block folded over. Straighten wiring and inspect brushes. Check slip rings. Reassemble and test generator. Good. check AC output, good."
So while at Cummins, I asked whether the generator will run with low battery voltage as that is what I was told was the reason it would not stay running. Essentially the generator has its own power source called the Quadrature windings and this provides power to the control board.
From a Tech: "once the unit is started, it should keep running as the quadrature windings should provide power to the control board. This should be independent of the DC Power."
I know in a related post there was discussion if these generators have an alternator and while I don't know about other types, apparently mine does not.
So although I need to replace my house batteries (they are what starts my generator) as they are long in the tooth and a bit weak, I am glad I didn't by new ones at the dealer and THEN still not have the generator work. I guess I am concerned about the mis-diagnosis as either they didn't know what the problem was and since it wouldn't start with just house batteries they assumed that was the reason OR, more disconcerting, they new batteries weren't the main reason but wanted to sell me batteries at an inflated price and then still perform tests etc to get the generator to run. The service manager and tech wanted me to stay an extra day or two so they could bring in batteries from another source.
Maybe it doesn't apply in all cases, but in this case it paid to take the problem to a qualified expert. I hope this helps others.
Jeff
Ps. Regarding the diagnosis this is what was provided to me:
"Under voltage - code 13
(After voltage regulation was enabled Output Voltage fell to less than 108VAC (90% of rated) for 5 seconds)
Corrective action:
1. Push the line circuit breaker to Off, start the genset and measure output voltage. If output voltage is normal, the problem is in the circuits external to the genset. If there is no voltage, test for and service a grounded or shorted main, field or quadrature windings (p.10-1) or grounded or shorted voltage sense transformer (p.11-5).
2. Replace the control board (p.11-1).
As your unit is appearing not to be producing voltage, this can be from several area:
1. Control Board is Non-Serviciable;
2. Issue with Stator:
a. The Quadrature windings provide power to the control board;
b. Main windings - AC output power; and
c. Field windings - create rotating magnetic fields
3. Brush Block or slip rings. "