Alternator Won't Charge Coach Batteries

[Captain Morgan]

After a week of camping in Myrtle Beach, we discovered that the coach batteries were loosing voltage as we headed home. This became evident when the low voltage alarm on the inverter sounded and shortly after my DW lost power to the DirecTV Receiver and Television. Everything appeared normal in the cockpit as the dash volt meter indicated the Alternator was working properly and the dash heater and wipers (it was raining) all appeared normal. One interesting observation was the volt meter on my GPS (must be connected to the coach system) indicated 10.9 volts and dropping on the screen. We pulled into a service station and I determined that the alternator and chassis battery were fine. We continued our trip home without a problem, although without 115vac.

Today I started troubleshooting the problem. I have a 2003 Pace Arrow 37A on a Workhorse W22 Chassis and the rig has a F73-1020 Battery Control Center under the hood. All visible wiring was in excellent condition and tightly secured. All fuses checked fine. All chassis related voltages checked at 14+vdc but anything to do with the coach batteries checked at 10.4vdc with the engine running. The solenoid that connects the two sides works fine (starts charging the coach batteries) when I push the emergency start switch, so I don’t believe it’s the solenoid.

It appears whatever senses the voltage on the coach batteries either isn’t detecting correctly or isn’t energizing the solenoid to allow the alternator to charge them. BTW, everything is fine when I plug into shore power.

Any thoughts?
Bob

[Captain Morgan]

After a week of camping in Myrtle Beach, we discovered that the coach batteries were loosing voltage as we headed home. This became evident when the low voltage alarm on the inverter sounded and shortly after my DW lost power to the DirecTV Receiver and Television. Everything appeared normal in the cockpit as the dash volt meter indicated the Alternator was working properly and the dash heater and wipers (it was raining) all appeared normal. One interesting observation was the volt meter on my GPS (must be connected to the coach system) indicated 10.9 volts and dropping on the screen. We pulled into a service station and I determined that the alternator and chassis battery were fine. We continued our trip home without a problem, although without 115vac.

Today I started troubleshooting the problem. I have a 2003 Pace Arrow 37A on a Workhorse W22 Chassis and the rig has a F73-1020 Battery Control Center under the hood. All visible wiring was in excellent condition and tightly secured. All fuses checked fine. All chassis related voltages checked at 14+vdc but anything to do with the coach batteries checked at 10.4vdc with the engine running. The solenoid that connects the two sides works fine (starts charging the coach batteries) when I push the emergency start switch, so I don’t believe it’s the solenoid.

It appears whatever senses the voltage on the coach batteries either isn’t detecting correctly or isn’t energizing the solenoid to allow the alternator to charge them. BTW, everything is fine when I plug into shore power.

Any thoughts?
Bob

[Onaqwest]

Bob, I had the same problem recently, however, my problem was the solenoid. Yours is a fault with the BCC (Battery Control Center ) board. I sent you a private message with a link to some schematic diagrams and trouble shooting procedures that may help. lou