Relay Problem

[DCTENT]

I have had the Realy Switch in Battery Compartment of 2006 Apex start clicking, while driving causing all lights to Dim as well as a slight pause in Engine, also has done same while in storage, HOWEVER evry time I get it to repair shop of course its working fine, Anyone else had this problem & what to do?.
Thanks Dave

[DCTENT]

I have had the Realy Switch in Battery Compartment of 2006 Apex start clicking, while driving causing all lights to Dim as well as a slight pause in Engine, also has done same while in storage, HOWEVER evry time I get it to repair shop of course its working fine, Anyone else had this problem & what to do?.
Thanks Dave

[Dale777]

Dave,

I have exactly the same problem. From the very 1st day that I picked my coach up at the factory on May 23, 2006, I have had this problem. About every 10-20 seconds, the battery isolator/relay in the battery compartment will click twice within 1 second. When this happens, the chassis voltage will drop from about 13.9 volts to about 12.7-12.9 volts and the headlights and dash lights will dim and the engine RPM will drop slightly.

Initially, the factory service center told me this was normal. A week later, they told me they fixed it, but they did not tell me how. After I left the factory service center, the problem continued to occur intermittently.

After I got back home in Texas, I narrowed this down to happening ONLY when the house batteries are discharged. When the house batteries are fully charged there is no problem. WRV had me take the coach to Cummins for them to check the alternater, but there was no problem found.

At one point just before the FMCA rally in Charlotte, NC, a factory support person suggested that it was a problem with the programming of the Vansco multiplexor that sends a signal to the relay to tell it to engage. He planned to send a replacement Vansco multiplexor to the rally to have WRV install it, but that did not happen. He also suggested that it might simply be a bad battery isolator/relay.

Subsequently, at the FMCA rally in Charlotte, NC, WRV had neither the Vansco multiplexor nor a replacement battery isolator/relay, so instead they installed a jumper from the alternator to the battery isolator/relay to force the relay to always engage when the ignition was on. However, this apparently caused another problem, since my fuel gauge no longer worked correctly. At the rally a technician from Guaranty RV cut the jumper and all was back to the previous condition.

Currently, the coach is in at a dealer in Texas for a long list of repairs, and this problem is one of them. So far, they have not resolved the problem.

If anyone has a solution to this problem, I would love to know what it is.

Dale Dowdy
2006 Alpine Coach 36FDTS

[DCTENT]

Dale:

Thanks for the response, My Coach also is in the shop here in Minnesota with many problems, I will advise the shop of your response regarding the Relay & if we find a solution, I will certainly pass it on!
Thanks Dave!

[EngineerMike]

Dale- sounds to me like a problem w/the Vansco because of the feedback issue w/the jumper voltage.
Ordinarily the Vansco commands chassis voltage to the solenoid relay when the house batts are up to a reasonable state of charge. That connects the charge source to both banks. Usually that'll be <~12.6V going to the solenoid to snap the relay shut & connect chassis batts to charge (relay should snap shut down to 7V per WRV last week). Alternator is putting out ~14.1V, and you are getting some feedback into other circuits (meaning Vansco has connected those); this voltage appears to be feeding back thru the Vansco programming to affect those circuits.
You would get that same 14.1V to the relay signal wire w/engine running (properly programmed) anyway cuz it is chassis batt voltage, which jumps to alternator voltage while running, going thru the Vansco to the solenoid.
Above is all excellent theory as far as it goes, but I can't explain why it all works OK w/the house batt's charged. Maybe somebody else can?