Possible alternator issues

1995 JEEP GRAND CHEROKEE

145,000 MILES • 4.0L • 6 CYL • 4WD • AUTOMATIC

TMAX5800

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So I think I may I have a problem with my car’s alternator but wanted to get more opinions. First of all, my car after about 5-10 minutes of driving will sometimes make a whining noise that gets higher pitched with more RPM’s but will be more audible the closer I am to idling. Secondly, the sound on my after market radio is very faint and only comes out of the dashboard speakers. Lastly, the electric door unlock and windows seem to struggle at times. After doing some research it seems like all of these can be pointed towards a possible alternator that has been going bad or just has an issue. Let me know what you think.

Mar 19, 2021 at 11:13 AM

ASEMASTER6371

CERTIFIED EXPERT
52,796 POSTS

Good afternoon,

Did you try removing the belt from the alternator and see if the noise stops? It may be the issue but need to confirm.

Can you upload a video of the noise so I can hear it?

I attached the belt diagram for you below.

https://www.2carpros.com/articles/replace-serpentine-belt

I would use a voltmeter to test the voltage at the battery with the engine running to see what the actual charging voltage is. 14 to 14.5 is normal. Check or spin all the other pulleys when you have the belt off to see if there is any noise.

https://www.2carpros.com/articles/how-to-check-a-car-alternator

I attached a wiring diagram for you below check all the fuses listed for power on both sides.

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-check-a-car-fuse

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Roy

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Mar 19, 2021 at 11:47 AM