Coach battery not charging

Found the problem. Broken connector. Soldered the connection and works fine.

Order a Cole Hersee 24213 relay from Amazon and install it in place of the existing relay. It will last the lifetime of the RV. The old one (on Winnebagos at least) looks identical but is 80 amp rated and has plain copper contacts. They burn up rather quickly, as they operate every time the engine is started. The CH 24213 has silver tungsten plated contacts and is rated at 200 amps and will probably never burn up. The old relay will have only one small terminal for the wire that operates the coil, the new one has two, you need to fabricate a short jumper to connect one of these two small terminals (either one, you pick) and connect it to one of the mounting bolts to complete the ground circuit for the coil. Very common problem.

https://www.amazon.com/Cole-Hersee-24213-Continuous-Solenoid/dp/B005K2429I/ref=sr_1_2?ie=UTF8&qid=1522722190&sr=8-2&keywords=cole+hersee+24213

Charles

The relay in my E-450 was in the front on the passengers side near the head light. The battery had to come out to gain access.

Thank you. I'll check it out..

Cruisineasy,

In my Ford e-450 it was in the fuse box near to the brake fluid reservoir.

pianotuna wrote:
The OEM isolation relay may have burned contacts. Mine lasted less than one year. I caused it to be replaced with one rated two hundred amps continuous.

There is also a fuse in the OEM charging circuit. Mine was a 60 amp. After the third time it blew, I replaced it with a 50 amp autoreset circuit breaker.

Where is this fuse??

According to the manual, it's the same one that engages when you push the button on the dash, (Not sure what it's called) to start the engine if the chassis battery is weak. Is that right??
If so, it's on the firewall. Maybe I have a bad connection with the wire that engages the solenoid when the key is on..

AWESOME!!! Where is the relay??? I looked for it but could not find it..

The relay mentioned above looks like this and is $15 on Amazon.

The idea is that the Chassis Engine, when running, sends 12VDC to one of the small terminals. The other small terminal is probably grounded.

That voltage closes the contacts between Chassis Alternator and Coach (House) battery, so it's charged when the Engine is running. The Coach/House cannot discharge the Chassis Battery because they aren't connected with the Engine Off.

Do you have an Assistant? If so:
Open Hood, Start Engine.
One of you put your DVOM across the Coach Battery.
The other of you put a jumper across the two LARGE terminals.
Voltage at Coach Battery goes UP?
If Yes, Test of Relay satisfactory and complete.
If NO, Relay is either not being powered through Chassis (one of the small terminals) OR other small terminal not grounded
OR if NO, bad Relay Coil (between small terminals) or bad Relay Contacts (between the Large terminals). Spend $15. Make it $17 and buy the Assistant a beer.

The OEM isolation relay may have burned contacts. Mine lasted less than one year. I caused it to be replaced with one rated two hundred amps continuous.

There is also a fuse in the OEM charging circuit. Mine was a 60 amp. After the third time it blew, I replaced it with a 50 amp autoreset circuit breaker.