Grave Yard Dead Brand New Battery.

[JamieGeek]

Originally Posted by dstankov

I could be wrong but those are one way diodes and the way I read the diagram is power from the coach battery can flow to the chassis battery (direction of the arrow on the diode) but the diode on the line going from the interconnect relay to the coach battery prevents power from going from the chassis battery to the coach battery (flowing in the opposite direction of the arrow).

Correct. The diodes are used to power the emergency interconnect from either source. (Note there are two of them both pointing at the interconnect). Thus power can come from the chassis ignition and power the interconnect or power can come from the coach batter and power the interconnect.

Note that the interconnect also controls a relay (to the left of the interconnect) that when you press the emergency start button closes and provides a direct short between both batteries.

[EA37TS]

Originally Posted by JamieGeek

Correct. The diodes are used to power the emergency interconnect from either source. (Note there are two of them both pointing at the interconnect). Thus power can come from the chassis ignition and power the interconnect or power can come from the coach batter and power the interconnect.

Note that the interconnect also controls a relay (to the left of the interconnect) that when you press the emergency start button closes and provides a direct short between both batteries.

Correct but power cannot flow from the chassis battery via interconnect to the coach batteries. So basically the coach battery(ies) can start the engine but chassis battery cannot start the generator. That is how it worked on my class C when my coach batteries died one time. The alternator had to charge the house batts for about 3 mins before the gen could be started

[JamieGeek]

Originally Posted by dstankov

Correct but power cannot flow from the chassis battery via interconnect to the coach batteries. So basically the coach battery(ies) can start the engine but chassis battery cannot start the generator. That is how it worked on my class C when my coach batteries died one time. The alternator had to charge the house batts for about 3 mins before the gen could be started

Not according to that diagram: When emergency start is closed both batteries are shorted together. Unless there is a diode in the relay/solenoid not shown.

[Chance]

Originally Posted by JamieGeek

Not according to that diagram: When emergency start is closed both batteries are shorted together. Unless there is a diode in the relay/solenoid not shown.

Do you know what the Interconnect Relay does? It obviously does more than connect the coach and chassis batteries together in parallel, but under what conditions? Otherwise there would be a manual switch that could do the same as a jumper cable (old motorhomes were often that way -- used a manual selector switch similar to boats).

If there is a brand and model number for the ones used on Axis/Vegas I'd like to research what it's full function involves.

[JamieGeek]

Originally Posted by Chance

Do you know what the Interconnect Relay does?

From what I gather the interconnect relay simply shorts the two batteries together when the emergency start toggle is held on.

[MrZip]

I think FORD is using Low grade batteries. A new 2015 coach and my battery was bad. I had to take the coach to a FORD dealer to get the battery warranted. Got a new battery and no more problems. Remember FORD/or GM is where you go for anything in the Engine compartment, concerning warranty

[Sandy]

I had a similar problem with my brand new Windsport 32N. Although with some difference.

I had my unit for a day or 2 and went to start the engine. Zip, zilch, nada. Not even enough juice to turn on the dash lights. Tried the emergency start but that didn't help. Finally put the charger on the battery and the engine fired right up. Didn't even have to wait for a little charge to run into the battery.

We went camping that day. Arrived at the campground and set up. I let the unit sit for a couple of hours and tried to start it again but it was as dead as a doornail . Being a little ticked off, I said "I'm going golfing" and off I went.

Came back after the round and tried again and it fired right up! Now what, lol. Did this several times over the next couple of days. Sometimes it would act as though it was completely dead and 5 minutes later it would start. Something else to add to the list of my wonderful Thor.

Called the dealership and they had no explanation. After the weekend I took it back to the dealer to have the 28 items that I had found wrong over the weekend to get fixed. They said they couldn't duplicate the problem but thought the battery was probably the culprit. They replaced it.

That was in May but so far I've only had the motorhome back for 4 days in total. (It's at the dealership now and has been there for the past 9 weeks again) So, I can't really say if the battery replacement fixed the problem or not. The few days that I had it back it seemed to work ok.

[up4306]

All,
As I mentioned in the original post, when the POP-a-Lock guy showed up with this "jump box" in his hand, the second he made the connection the RV started right up. The volt needle in the dash made no radical move indicating trouble.
Since that day the RV has started every time. I agree the battery is the culprit and will replace it before heading out again.
Thanks for the input everyone. Great Forum here.
David