Alt light stuck on.

[MustangShane]

Driving to work I pull in the parking lot and my alt light comes on. Check the guages and everything is in the appropriate range. So I shut it off and go inside. Driving it home the light stays on about 70% of the trip. Charging seemed fine no dimming of lights or anything. I get home visually check the connections and do a wiggle test. Light stayed on but the system was pumping out 14.2v without accessories and 13.24v with everything minus the wipers. Any ideas guys?

 

[Critter92X]

Just a guess, but your alt. brushes are probably wearing thin.

 

[MustangShane]

That would make it trip the alt. light?

 

[Critter92X]

Yea, that would probably make your alt. light come on if they are wore down enough.

 

[MustangShane]

Yea, that would probably make your alt. light come on if they are wore down enough.

But to say that after its charging the system fine. I mean 14.2v unloaded and 13.24v when i turned on the lights, int. fan full blast and the rad. fan ? Just seems like it doesn't add up to me. Well I have another alternator so if this is the problem then okay.

 

[Critter92X]

Yea I admit it sounds like the alt. is charging but if I had another alternator I would try it to see if the problem goes away.It's only about a 15 min. job that might save you from getting stuck away from home.It could be a bad wire to the light but that might take longer to check out than changing the alt. If the alternator/reg. change don't do the trick you can eliminate that and go from there and check the whole charging system from the battery to the light and ignition switch.

 

[MustangShane]

Well its something I didn't want to have to do. I'll probably get to it after this weekend an we'll see.