Chassis not charging coach batteries, need some help diagnosing

[Gilman]

I had similar issue with 2017 Essex. Check your solenoid that connects to your house n chassis batteries.

[lotpainter]

Similar issue on my DP. Found broken battery cable going to house battery's. Also check fuse.
House battery's are usually deep cycle and chassis are starting battery's.

[kayla44]

Shouldn't house batteries be 6 volt deep cycle? When checking with multi meter shouldn't reading on each battery be in the 6+ range? Not 8, or 13-14

[lotpainter]

You could have either but most likely 12 volt. IF they are 6 volt they will be tied together positive to minus to make the two battery's 12 volt. If more than two another bank would be the same then the banks attached together pos to pos and minus to minus so as not to be more than 12 volts for the entire battery bank. The total voltage must be the same as the chassis battery's. They charge of the same alt. Best untie all battery's and charge and test each one.

[jdmalibu]

So I believe my solenoid failed again, started with now power to fridge motherboard, the realized dead coach battery while plugged in. The I checked the converter fuse which are not broken. Also I’ve been listening for the converter charger to run and it’s been silent.

I’ve used the Boost quite a bit lately, and even bought a new coach battery as I thought that was the issue.

So reading through this thread I will order the 200Amp model, with a bit more resting first to make sure it’s the solenoid.

Learning a lot this summer about the RV, seems like there is always a Next repair to make.

[Sbrownstein]

Originally Posted by jdmalibu

So I believe my solenoid failed again...

Easy test if you have a voltmeter. First measure the voltage across the small terminals, should be 12 volts if solenoid is engaged. On diesel coaches the voltage may be lower since many vendors fire the solenoid with 12 volts and then "hold" it engaged with pulsed 12 volts to avoid unnecessary heating.

If the solenoid is engaged, measure the voltage between the heavy duty connections. It should be "0" if the solenoid is working. Anything else indicates that the solenoid is not up to snuff.

If the solenoid is not powered, try doing the same thing while someone holds down the boost switch, which will manually fire the solenoid to parallel chassis and house banks.