Skip the auto shop - Our mechanics make house calls

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

asked by on

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Auto shutdown relay clicks and won't stop until negative cable is off

Hi, thanks for writing in. This may suggest a short of some kind causing the power to continue to be supplied to the relay. The starter relay is a small unit near the starter that directs power to the starter...

Q: When driving, my engine sounds like it is missing

You definitely have a misfire. It sounds like the misfire gets worse under load, which is why the Check Engine Light starts blinking. This indicates the catalytic converter is being damaged. A misfire under load is usually caused by a...

Q: Crankshaftpositionsensor

A failed crankshaft position sensor can cause symptoms like this. When you crank the engine, the engine control unit looks for a signal from the crankshaft position sensor to determine where each cylinder is. When the signal is received, the...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...