[Eonich]

Hoping for some help. I have a 2006 Commander, 5.7 l. I have not had any issues with the battery going dead but I frequently am seeing the battery/charging system warning light. It is not on when I start the car but the warning light will illuminate periodically. It will remain lit until I shut down the engine. The next time I start the car, no warning light. Then at some point later the warning light will come on again.
had the battery/charging system check at a local parts store. The battery showed 12 or perhaps a little less with the engine off. Voltage shows pretty much the same with the engine running and alternator functioning.
The warning light seems to come on when there is a bit heavier voltage load. Using the heated seats is one example.
My question; if I recall correctly, shouldn’t the alternator be charging at a slightly higher level? 14 volts is the number I have heard. Could the barely 12 volt output be a sign of a failing alternator? Would that case the warning light. Are there any other reasons the warning light would be coming on?
Thanks in advance for any help or advice.

 

[Big Blue]

Hoping for some help. I have a 2006 Commander, 5.7 l. I have not had any issues with the battery going dead but I frequently am seeing the battery/charging system warning light. It is not on when I start the car but the warning light will illuminate periodically. It will remain lit until I shut down the engine. The next time I start the car, no warning light. Then at some point later the warning light will come on again.
had the battery/charging system check at a local parts store. The battery showed 12 or perhaps a little less with the engine off. Voltage shows pretty much the same with the engine running and alternator functioning.
The warning light seems to come on when there is a bit heavier voltage load. Using the heated seats is one example.
My question; if I recall correctly, shouldn’t the alternator be charging at a slightly higher level? 14 volts is the number I have heard. Could the barely 12 volt output be a sign of a failing alternator? Would that case the warning light. Are there any other reasons the warning light would be coming on?
Thanks in advance for any help or advice.

@Eonich ;

You can get the battery tested first, just to be sure it's good & healthy, but, it sure sounds like a bad alternator to me.

 

[rblapham]

The parts stores can usually check the alternator also. In car I believe but I have never had it done. Yes with engine running the volts should be higher - 13 or 14 VDC

 

[andreve1964]

I recently had my alternator overhauled and found that the diodes on the inside had loosened from the PC Board. They are held on by what seems to be ceramic glue.
The revamp was inexpensive and now i get over 13V outputs.
Problem with under performing alternator is the battery will get cooked from over use as it makes up the output shortfall from the alternator.
Good luck!!