Alternator/electrical system question

[athens7]

While chasing my little green turn signal indicator light problem, I find that when the car is at hot idle, turning on the headlights will shut down the radiator fan. As soon as I cut the headlights off (parking lights still on), the fan turns back on. This was replicable 100% of the time. Is it part of the car's design to do this, or is this a sign of a problem? It would seem to me that the car should be able to run both lights and fan simultaneously while running, especially at a hot idle when the car needs the fan the most.

 

I am wondering if my alternator is having a problem. I have heard that as Banner batteries die, they can take the alternator with them, perhaps as the result of constantly trying to charge the battery. What test might I perform to check the alternator, and what other issues might cause the car to not be able to power all of it's electrical systems while the engine is running?

[pksurveyor]

My Banner battery died without warning. It lasted about 4 years. Your 5 years old battery probably is at its last leg.

[athens7]

My 5 year old battery is in a legally compliant disposal facility. I have a shiny new PC680MJ with billet hold down (middle aged car guy bling). I am worried that the alternator has been burned up by the Bummer as it was dying.

[scannon]

Still sounds very much like a ground problem to me. Go through and clean all ground wires/cables where they mate to the frame or engine. You might also add a ground cable from the battery to engine block or battery to frame if the car doesn't already have both.

[slomove]

  athens7 said:

My 5 year old battery is in a legally compliant disposal facility. I have a shiny new PC680MJ with billet hold down (middle aged car guy bling). I am worried that the alternator has been burned up by the Bummer as it was dying.

 

Man, looks clean.

 

I don't know how you do that. I looked under the bonnet today after last weekend's 300+ mile trip and there are sand dunes, rocks, piles of butterflies, wasps and other crap in the engine compartment. Once a while a take a power washer to flush it all out but I guess I will never get it really nice again. Oh well, maybe the Georgia roads are just cleaner.....

[powderbrake]

  scannon said:

Still sounds very much like a ground problem to me. Go through and clean all ground wires/cables where they mate to the frame or engine. You might also add a ground cable from the battery to engine block or battery to frame if the car doesn't already have both.

I ran a seperate ground wire to the fan and to the lights, they draw a lot of current.

[athens7]

  slomove said:

Man, looks clean.

 

I don't know how you do that. I looked under the bonnet today after last weekend's 300+ mile trip and there are sand dunes, rocks, piles of butterflies, wasps and other crap in the engine compartment. Once a while a take a power washer to flush it all out but I guess I will never get it really nice again. Oh well, maybe the Georgia roads are just cleaner.....

 

12,000 miles on the car. I have never put a pressure washer or any water under the bonnet. I did buy a bottle of Dirt-X to put on the engine from the same guy I got the light weight racing air for the tires from :jester:.