Originally Posted by frederick w
After a 5 hr. trip the MH sat for 3 days in which the lights were on
for short intervals.
The Aux. disconnect didn't work because the bat. voltage dropped to 10.
I wonder what took the2 house bat. down so quick. After an hour on shore power, the aux. switch worked and now the 2 batteries. read 12 volts.
The interstate batterie dates weren't pricked out on date tab and no date codes on sides of batt.
Now I don't know how old they are. Don't know if bar code will give date.
Thanks in advance.
If the batteries have gone below 11.3 volts. it's likely they will never return to a full state of charge. 10.5 volts is considered 0% of charge or completely dead.
Deep Cycle Battery FAQ
As mentioned earlier they may just be too old to take a charge, the solenoid that switches on with the ignition may be faulty and they dont charge from the engine alternator, or the house charger isn't recharging them from shore power.
You can check the solenoid by disconnecting from shore power and starting the engine. Go to the energy management center and check both the house and chassis batteries. If the chassis battery shows 13.4 - 14.5 volts the engine alternator is working. If the house batteries don't show similar voltage the transfer solenoid is bad.
With the engine off and connected to shore power you should see around 13.7 volts on the house batteries. If you see 12 volts or less you have a problem with either the transfer switch or the house baytery charger.