Weird electrical issue

[USAF Long]

So last Friday I went to unlock my car and the unlock on the fob didn't work. Tried it again a few minutes later and the car unlocked but my clock in my gauge cluster had reset and my stereo lost it's programming. So after setting the clock and date, and my stereo's clock and settings, I went about my way thinking that was odd. Drove down to Las Vegas that afternoon and everything was fine except my headlights seemed to be getting brighter and dimmer like a slight electrical surge... not bad but I noticed it.

The next day I'm down in Vegas and the car cuts electrical to the stereo and the dash warning lights all come on while driving for like 2-3 seconds. The car never turned off anything but it was almost like someone turned off the key for a second and turned it back on.

Later that night while driving it happened again and the lights were doing the slight surge again. Then it was fine on Sunday and Monday.

Last night after work I came out to my car and the clock and radio were reset again. I set them, drove home, drove to dinner, everything is fine, no surging in my lights.

I was kind of thinking the surging lights could be a sign of alternator getting ready to fail but why would my interior accessories lose programming?

I'm going to clean my battery terminals really good tonight even though I don't think there's any corrosion on them. Other than that, is there an interior electronics control module that could be failing? Ignition switch? Alternator? I'm stumped. Not sure on the surging lights, but that could be something else.

I'm getting sick of this B6.

[john_gonzo]

Quick test to see if alternator is charging: With engine at idle, measure the voltage across the battery posts. Should be about 14.2 Volts.

All those 'puters need a solid supply voltage. When that goes away, most bets are off as to behavior of said electronics.

[walky_talky20]

If the charge voltage is falling off, it could be failure of the alternator brushes. This can be a $5 fix.

DIY $5 Alternator fix

[john_gonzo]

Or a $17 fix of the alternator slip rings: Alternator-new-slip-rings

[USAF Long]

I'll dig out or buy a multimeter and see.

Sent from my VS870 4G using Tapatalk

[daught]

I'll dig out or buy a multimeter and see.

Sent from my VS870 4G using Tapatalk

Are the lights pulsating fast? Is the pulsation RPM related? If it is, a phase on the alternator is not working. Some meters might not catch that.

[diagnosticator]

Your problem has nothing to do with the alternator. Under the dash, there is a three post threaded connection for the several wiring harnesses. Make sure the 8mm across flats nuts are tight on the threaded studs. These posts are energized all the time, disconnect the battery before checking the nuts. If the nuts are tight, check the CECM under the driver's side dash above the horizontal row of relays. The CECM controls all of the exterior lighting. The door locks and interior lighting is controlled by the Comfort module. It is possible that heavy rain has caused the plenum to overflow, sending water down onto the CECM, and continuing to drain down to flood the space under the driver's side footwell carpet where the Comfort module is located.

[Shortrun]

I would be looking at the battery. Or any connection either on the plus side or the ground.