Community Forums

CrazyKnight · 05-02-2013, 02:39 PM

Ok I have searched for the last three days and a few glasses of wine. I am trying to figure out why the alternator fail and chime come on with the engine running and you turn on the generator. It has done this before and I guess the computer is sensing an over voltage condition and turning on the alt light and chime. Now the hard part, I just installed a great solar system which should be on all of the time, but I can turn off the system. It charges my L16's at 15 volts as recommended but as soon as I start the engine the alternator light and chime come on in less than 15 seconds. If the solar or generator are turned off....no light/chime. I have read all about the relays and isolators and had to fly out of town for a family emergency so as soon as I get back to the coach next week I will check all of the voltages in and out of the alternator.

I am just reaching out to the group to see if anyone has the answer or ideas so when I get to the coach I can have a head start. We take a month long trip in 3 weeks. Thank you in advance for ANY and all information and help.

DtBt · 05-02-2013, 04:48 PM

If the chassis battery voltage is above a threshold something like 13.7 to 14 volt (guess) the alternator will shut down to prevent an overvoltage situation. This will cause the alarm. You could increase the load like turn on the headlights and that should be enough to remove the alarm. If in fact something like the solar controller or inverter charger is set too high the battery(s) will cook as well.

CrazyKnight · 05-02-2013, 07:46 PM

Another thought, how would I run the AC units while driving. Would the load from the AC units be enough load to cause the light/chime to go out. My 4 L16 interstate batteries charge at 14.8 to 15.6 on all forms of charging yet alone if I ever equalize. Solar set at L16 setting 15.4 volts. I will check electrical schematic from Monaco when I get home for diodes and relays.

DtBt · 05-03-2013, 04:30 AM

Dash air will load the chassis batteries. Roof air is Gen/shore power only. I would think the solar would charge the house batteries only unless bridged while under shore power (BIRD or other control activated).

Burgy · 05-03-2013, 07:14 AM

On our 2004 dynasty... If I have the genny running and set to auto start on the remote panel the alarm will chime, the minute it set the AGS to manual/push the alarm never comes on.
Xantrax inverter, RC7 AGS, Onan 10K

Sounds strange but it's what I have found with mine anyway.

CrazyKnight · 05-03-2013, 01:09 PM

Will look into the charging system which charges the coach/engine batteries only after the house batteries are charged. Could the BIRD, which I think I read I have, be putting all the solar/generator voltage to the engine batteries AFTER the house batteries are fully charged and then telling the computer, hey run away alternator...over voltage condition and then it shuts down the FIELD voltage ?

I will know more when I get my electrical diagram off my laptop..at home.

Thanks

deSanford · 05-03-2013, 02:04 PM

I had the same problem Graig and Angie. It turned out to be a relay that was bad. Navistar service techs in Coburg sent me a new one and problem solved. When I went to Quartzsite with it 'BONGING' etc. the guys there did their best to figure out what was wrong. Thankfully it wasn't the alternator or a battery problem. Problem solved. deSanford

CrazyKnight · 05-04-2013, 08:52 AM

Quote:

Originally Posted by deSanford

I had the same problem Graig and Angie. It turned out to be a relay that was bad. Navistar service techs in Coburg sent me a new one and problem solved. When I went to Quartzsite with it 'BONGING' etc. the guys there did their best to figure out what was wrong. Thankfully it wasn't the alternator or a battery problem. Problem solved. deSanford

I think we just missed your visit in Q, but we had a blast with the gang. We are hoping that will be our problem or some simple form there of. Thank you for the direction and ideas. When I make it back to the coach let the games begin.

Thanks again

Larry and Suzette · 05-22-2013, 06:32 PM

I have a similar problem. With show power connected I get the alarm with the engine running. No alarm when going down the road.

Also I have seen the dash volt meter go to the peg and go to 8v when I shut the engine off. Restart and evey thing normal.

desanford, Do you remember what relay was bad?

2008 HR PDQ

deSanford · 05-22-2013, 07:46 PM

Sorry I don't remember which one. The service guys at Coburg can tell you over the phone. deSanford

Larry and Suzette · 06-16-2013, 02:18 PM

I asked this question of Monaco/HR via their web site tech support; "Question or Comment
On my 2008 HR Endeavor when I am connected to shore power and run the engine I get an ALT Fail alarm. This also happens when both the engine and generator are running.

Will this damage anything?
Is there some component that is defective?"

And received this answer form mcctech;
"There is not an issue with that. What happens is that you are charging both battery banks and when the boost solenoid connects the alternator sees a higher voltage coming from the house batteries than it is producing and it shuts down causing the alt fail light to come on.

Frank Phillips
Technical Advisor
877-466-6226
"

YC1 · 06-16-2013, 04:53 PM

Frank has a great answer. The BIRD system senses a charging voltage via alternator, solar, generator, or shoreline. Once the Bird system senses a charging voltage it combines the batteries. With the charger going the voltage is high enough to cause the alternator to fault as folks have found under some conditions.

The Bird system has a cutout feature that senses ignition voltage and will actually cut the Bird circuit off when the generator is running so the Generator can run the AC's etc and not interfere with the alternator. This is a strange thing to me because shoreline is no different than generator as far as AC is concerned. One can start the RV and still be plugged into shoreline and the Bird would activate which should cause the same symptoms.

I'm thinking under most situations the chassis batteries are low enough to hold the charging voltage down so it does not confuse the alternator. However driving all day with the generator running for the AC's would bring them up and very possibly bring the battery voltage up high enough to confuse the alternator.

So for the OP there may be a stuck relay and I can help isolate that when ready.

I'm sure some of this is clear as mud.