[qcj]

There have been several occasions where my check engine light would come on and I look at the Detroit pro indicator and it would say aux output open circuit. It will stay on about 15 seconds and go off, then maybe come back on and go off again, and not come on anymore during an all day trip. This always happens at the beginning of a trip never during a trip. One would never know anything was happening if you did not see the light. Then I might not see it again for several months. Everything seems to be operating as it should. Looking at the DD codes in my booklet it would be #31.

[ashley]

Chappell had that happen with a different code, happened 3 times went away never came back

[folivier]

I plan to pull the connector plugs on the DDEC module at the engine and clean the pins with Deoxit next week.
I use VMSPC and occasionally get a comm fail on some gauges, also have gotten a check engine light a few times.

[qcj]

Where is this plug Forest?

[folivier]

I'm talking about the ones on the passenger rear side of the engine. There is a rectangular box that has multiple sets of wires going into it. I will pull them and clean the pins. I figure it can't hurt, if any pins are oxidized the signals might be low.
If you're not running VMSPC you should be. http://www.silverleafelectronics.com/node/6
Quite a few of us are using it.

[encantotom]

a few thoughts. i had ecm problems and it took an old salty experienced DD guy to find it. when the engine compartment got wet it happened the most but sometimes just while driving. i got a check engine light then the engine would derate and sometimes shut off.

after a ton of time and effort, a mechanic found that the ddec unit on the engine had two issues. 1st is it had a bolt that had dropped down from somewhere higher on the engine and gotten wedged between the ecm and the block. it had not worn a hole yet but would have. the ecm is isolated with rubber grommetts.

the other was that one of the pins was bent over. it was an unused pin, but it did prevent the plug from seating all the way which allowed water to get in and cause the fault.

once the pin was straightend and the bolt removed i never had another problem.

for your particular fault, it should also flash a code. if you were running vmspc it would store it. i did find this link for a similar code

http://www.justanswer.com/heavy-equipmen...n-cir.html

http://www.dieselenginetrader.com/diesel...eadid=3001

if you do a search on the error code you got you will find quite a few discussions about it

tom

[qcj]

OK I know where that is. I had Bernd, my local diesel gurus, check on this several months ago and did not find anything. He zeroed all faults and I went months with no problem. Then the other day it came again. I guess what I really would like to know is how important is it. It doesn't seem to have any effect on anything??? I will check out Module and thank you. The first time I had this was on the way to Speatfish.

[qcj]

Tom, thanks, I have googled it also, but no results. I will keep trying and if it does not put me on the side of the road I'm not that worried. These motor homes are quite complicated for an old boy like me.