i have a 2003 s type v6, engine would not turn over, battery check ok, alternator not registering, replaced alternator and recharged battery, battery light on, how do i get it to go off or is the battery really bad?

 

If you purchased an alternator from a parts house, the warning light may stay on. It's always best to have the alternator removed from the vehicle and overhauled by an automotive electrical specialist.

 

Do you still have the old alternator? You may have to swap the internal control module over to the new alternator. An aftermarket alternator may charge just fine, but the new control module won't communicate properly with the car, thus the warning light.

 

Different car but similar outcome.

https://www.jaguarforums.com/forum/x...tor-lt-238208/

Much discussion about alternators and wiring.

 

car would not turn over, battery ok, alternator not working, replaced alternator and recharged battery, how do you get the battery warning light off

 

If you replaced the alternator with a non-OE unit, you most likely won't be able to get the battery warning light extinguished. The original unit has control circuits which communicate with the ECU; after-market units will most likely charge okay, but lack the ability to interface with the ECU and the light remains illuminated regardless of charging status.

 

How many threads are you going to post about this?

https://www.jaguarforums.com/forum/s...-light-238847/

 

Perhaps he will keep asking until he gets the answer he wants...

 

Hi uncleken,

I have merged your two threads on the same topic so all the responses will be in the same place. Please do not start any additional threads on this topic.

Most auto parts stores have analyzers that can test your battery, starter and alternator/charging system. Also, they can scan your onboard diagnostic system to see if there are any stored powertrain-related Diagnostic Trouble Codes (DTCs) that could indicate some other electrical problem.

Corrosion on battery power connections and critical ground points can lead to insufficient battery charging and/or low voltage to the ECM and other critical components. One quick check is to connect an OBDII scan tool and see what voltage the ECM is reporting. If the ECM is seeing voltage significantly lower than the voltage at the battery terminals, you may have a wiring problem. For example, common trouble spots are the battery negative cable ground point on the body and the two ends of the engine ground strap, but there are many others.

Cheers,

Don

 

sorry about double post, couldn't find my first post, thanks for the information. always have great hep herer

 

Yes, it's still on the car. I've got to do some other things before I take it off. I'm trying to get one rebuilt if possible.