Electrical power cuts out

[Loover21]

While my engine is running my lights will turn off briefly as well my gauges for fuel, oil life etc will turn off. It does not seem as though I am losing engine power though. My heat also died at the same time a couple of times but the last time the power cut out the heat stayed on. I had my hood up the last time this occurred and it stated making an odd side from the side where my belts are located but I could not pinpoint where it was coming from as it only lasted a few seconds. My battery is new this year and I ensured that my alternator is charging the battery using a multimeter. Any thoughts?

Its a 2002 Grand Prix GTP 3800. No mods!

 

[falcongt]

I would check all major wire connections (battery, starter, alt, ect) for corrosion and tight connections. I would check ALL fuses inside and under hood to make sure non is blown but also to make sure they are fully seated and not flopping around. I would also wiggle the ignition key the next time it happens. It sounds to me like something is loose.

 

[dbextreme]

I had a problem:

Radio cut off, windows quit working, gauges quit working, lights would cut off when I hit the brake, other weird stuff.....

I purchased an ignition switch because all symptoms lead to that. Before I installed it I checked my battery, I pulled the positive terminal off and it was gummed up. I cleaned it all worked fine. If all your stuff is new, maybe something didn't get tightened down. If you are hearing "sounds" around your belt area (beside your battery) you may have arching at the terminals. But as falcon said, check terminals, grounds, the lead to your alternator, ect..

 

[Loover21]

I will go ahead and check the things that you pointed out, I just don't have the time now as I'm heading out of town.
Another symptom that I just noticed is when I turn on my A/C my lights turn off, when I turn the A/C off , my lights come back on!