Lost connection: House battery to Converter (SOLVED)
Boondocking way out west.
1995 Tioga Montara Class C on Ford F350 chassis, 460 V-8. Upgraded to BestConverter Ultra III in 2014.
Inverter chirping in the afternoon from low voltage, so started Onan generator. 14.4 volts on meter, later dropped to 13.9. Around this time the fan in the converter started pulsing low / higher. I thought this was because the battery was charged.
Turned off the Onan and everything went black.
Checked converter bottom 30A fuses (unscrew lower compartment). If fuses removed while Onan is on, lights go out. Implies power converter is the only source of 12 VDC.
Fan does not come on, implying the battery is not putting any load on the charger.
Turned off Onan and checked supply line from house battery. Less than one volt (dropping slowly because of backfeed from power converter.)
Key symptom: Converter no longer has a connection to the house battery, either to charge it or get power from it.
Yet battery is charged and starts the generator through the heavy cable.
Chassis manual shows “Modified vehicle power feeds” 50A fuse in Power Distribution Box. Pulled this with difficulty: OK.
Key diagnostic question: What has changed?
Wrote everything down, ran Honda EU2000i overnight to power furnace and most importantly the VPAP machine.
The problem is now fixed. Can anyone diagnose it based on the clues above?
1995 Tioga Montara Class C on Ford F350 chassis, 460 V-8. Upgraded to BestConverter Ultra III in 2014.
Inverter chirping in the afternoon from low voltage, so started Onan generator. 14.4 volts on meter, later dropped to 13.9. Around this time the fan in the converter started pulsing low / higher. I thought this was because the battery was charged.
Turned off the Onan and everything went black.
Checked converter bottom 30A fuses (unscrew lower compartment). If fuses removed while Onan is on, lights go out. Implies power converter is the only source of 12 VDC.
Fan does not come on, implying the battery is not putting any load on the charger.
Turned off Onan and checked supply line from house battery. Less than one volt (dropping slowly because of backfeed from power converter.)
Key symptom: Converter no longer has a connection to the house battery, either to charge it or get power from it.
Yet battery is charged and starts the generator through the heavy cable.
Chassis manual shows “Modified vehicle power feeds” 50A fuse in Power Distribution Box. Pulled this with difficulty: OK.
Key diagnostic question: What has changed?
Wrote everything down, ran Honda EU2000i overnight to power furnace and most importantly the VPAP machine.
The problem is now fixed. Can anyone diagnose it based on the clues above?
