Strange alternator failure warning

[WheelingIt]

This will be a tad long but hoping some of you experts can guide us on where to go next on this problem. Here's the story.

About 2 weeks ago while starting off from a campground in FL we got an alternator failure warning on the dashboard. We took the rig to a local place specializing in Cummins engines and they checked everything obvious...alternator, chassis batteries, voltages. From an Engine point of view all was fine..the alternator was doing it's job and the batteries were fine. We left there and the indicator warning had gone so we figured all ok. Well not so.

Next time we started the rig same problem. We've now driven it several times with the same symptoms:
1/ Alternator warning light comes on when we first start driving (warning light is not on when we stop and idle)
2/ The warning comes and goes as we travel. At times the entire dashboard including the gauges go completely out and reset. Cruise control and turn signals are not affected.
3/ The warning plus intermittent reset of the dash keeps going for about the first hour of driving then it stops and everything runs normally. No warning for rest of drive.
4/ Voltages always show fine the whole time, around 13.9-14V.

Given the whole weird resetting issue we thought it might be a moisture or loose wire in the dash, but we just can't find anything obvious. We've pulled out the whole dash and tried to look at the mass of wires back there..nothing. The alternator seems to be working just fine and we can't for the life of us understand why the problem goes away after an hour of driving??

Any ideas on where else we can look?

Oh we have a Holiday Rambler Endeavor 40PDQ 2008 if that helps any.

[walt2137]

Sounds like your hamsar relay is the culprit on the alt light, on the dash going and coming the first thing I would check or do is clean and re tighten all dash grounds, if that don't get the dash problem I have no idea.

[WheelingIt]

Quote:

Originally Posted by walt2137 Sounds like your hamsar relay is the culprit on the alt light, on the dash going and coming the first thing I would check or do is clean and re tighten all dash grounds, if that don't get the dash problem I have no idea.

Ookay....so asking a very silly question no doubt. Where is the relay and do I need to swap it out completely?

We will do some wire tightening on the dash, but I still don't get why it stops after an hour of driving. This whole dash business only started the day our alternator problem started and both only last for about an hour coming and going. It's a bit maddening.

[walt2137]

Quote:

Originally Posted by WheelingIt Ookay....so asking a very silly question no doubt. Where is the relay and do I need to swap it out completely? We will do some wire tightening on the dash, but I still don't get why it stops after an hour of driving. This whole dash business only started the day our alternator problem started and both only last for about an hour coming and going. It's a bit maddening.

I don't know where it is on your coach call Monaco tech with your coach number and they will tell you and yes you need a new relay.

[WheelingIt]

Quote:

Originally Posted by walt2137 I don't know where it is on your coach call Monaco tech with your coach number and they will tell you and yes you need a new relay.

Thanks so much! Very happy to have a lead to check out. We'll get on it and i'll let you know how it goes.

[moisheh]

We had a problem where the dash gauges would just quit. Odometer as well. Everything else was working. I called Monaco and there is a known problem at the right rear wiring harness. There is a plastic connector in the wires that connect the Cummins computer to the Monaco setup. They should have used weathertight connectors. The connector is very hard to find as there are many wire bundles in that area. Along the frame rail and wrapped in electrical tape. Perhaps that is your problem?

[WheelingIt]

Quote:

Originally Posted by moisheh We had a problem where the dash gauges would just quit. Odometer as well. Everything else was working. I called Monaco and there is a known problem at the right rear wiring harness. There is a plastic connector in the wires that connect the Cummins computer to the Monaco setup. They should have used weathertight connectors. The connector is very hard to find as there are many wire bundles in that area. Along the frame rail and wrapped in electrical tape. Perhaps that is your problem?

Could be. We swapped out the relay today so we're going to see how the rig does on the drive tomorrow. If we're still having dash issues I will follow this idea up. Cheers very much for the tip!

[WeBeGone2]

I actually named my hampster. (HAMSER) I call him Jorge. Beepers come and go. Gen light flicks, windshield wipers come on by themselves. ATC lites up etc. I called the first owner and he swears that he killed no one in the coach leaving the ghost for me. I have tightened every nut, screw and connection. To no avail. Now I look forward to the distraction as I drive.

Quote:

Originally Posted by walt2137 Sounds like your hamsar relay is the culprit on the alt light, on the dash going and coming the first thing I would check or do is clean and re tighten all dash grounds, if that don't get the dash problem I have no idea.

[WheelingIt]

Whoo Hoooo...it worked! Switching out the relay and tightening whatever wires we could has solved the problem. Thanks so much for the help everone !! Once again, the forums rock. Nina