Q: All 4 heated O2 circuit high, and alternator not charging

asked by on October 30, 2016

Ive swapped out alternator with a good one from my other stratus and still no charging.all 4 heated o2 circuit high and I've replaced all 4 O2 sensors and replaced PCm. I'm very mechanically inclined and i cant figure this out. Please help!

My car has 132000 miles.
My car has an automatic transmission.

As you may know, the alternator is unrelated to the O2 sensors and these will not impact the charging of the battery. The charging issue may be related to a bad voltage regulator which is a unit that monitors the charging of the battery by the alternator to be sure that it does not over charge or under charge the battery.

When this is not working properly, this can cause an otherwise good alternator to not charge the battery properly. I would recommend having the alternator and voltage regulator tested to determine what may be causing the problem. If you would like consult another expert for a second perspective, a certified technician from YourMechanic can come to your car’s location to help diagnose the charging problem and pinpoint the fix.

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