Alternator Not Charging Chassis Battery
1996 Lazy Daze on a Chevy P30 chassis. I have an alternator that is not charging. The simple answer might be that it is the alternator but these Chevies have an "exciter" circuit that determines wh...
Forum Discussion
I get 12.2 V on the battery with the engine on or off.
I don't get 13v+ with the engine on anywhere, including the alternator. Here are the voltages I get with the engine on:
Batt - terminal to terminal - 12.2
Alt red terminal to batt negative - 12.2
Isolator 1 - 12.2
Isolator 2 - 12.2
Isolator E - 11.7 (this is strange - lower than the others)
Isolator A - 12.2
Sounds like bad alternator, don't get caught up in the "exciter" idea
Quick test
On the isolator, Move the alternator wire on top of the chassis battery wire, usually bat 1, but verify this before moving
Start the engine check for voltage
If you have voltage it's a bad isolator
Test two
No voltage move the 'E' wire on top of the other two
If still no voltage bad alternator
Replace wires to normal positions after testing, before putting away the tools
