Time for a new alternator?

[uh60james]

I have noticed the last few nights when I have been driving the lights are going bright and dim when at low RPM's. For those who have ever drove a humvee it looked just liked the lights do when you first start them.

 

[BrooklynBay]

Did you check your voltage when this happens? It could be a bad dimmer switch for the dashboard lights. I have that on mine. Do you have this problem on your headlights? Did you check your battery terminals for corrosion?

 

[uh60james]

Headlights, interior lights, dash lights all do it. I replaced the battery about 2 months ago with a Die-Hard.

 

[shamaal]

The local O'Reilly autoparts tests alternators, perhaps there's one or similar type store in your neck of the woods. Likely problem would be regulator or blown diode. I've never used them so I can't say how comprensive the test is.

Otherwise a bad connection as BB suggests is a very distinct possibility. Aside from the battery post, where the cable connects to the connectors gets eaten up where they mash the wire. Generally speaking you would have problems starting, but I've seen faulty connections cause other problems as well.

On my 91 there is a slight dimming between high revs and idle but not significant.

 

[ma96782]

Disconnect your battery and alt......take them down to a large auto parts store....they'll usually test them both for free....while you got the battery disconnected clean up the post connectors.

Check the wire condition of the alt plugs.

Make sure the battery is fully charged before putting it back into service.

Aloha,Mark

Headlights, interior lights, dash lights all do it. I replaced the battery about 2 months ago with a Die-Hard.

Also, check your ground strap and cable condition.....BTW, I don't trust Die Hard (SEARS) they have been know to sell used batteries as new......and they have mis-diagnosed my vehicle's elec. system problems on more than one occasion, after selling me a new battery (of course).