Parking Break, Break Fluid, and Battery light flickering together

[AV325i]

I have an 89 325Xi that sometimes has the parking break, break fluid, and battery light flicker at exactly the same time. The blower motor and headlights also dim in time with the flicker.

Does that give any help is telling where the short is at? This problem comes for a few days and then goes away, but is happening more and more frequently.

I'm not sure how to go about troubleshooting this.

Thanks!

[BlackSpeed66]

My car does this when it's cold and I haven't started it for a week or so. After a few minutes of warm up, it goes out. You might want to have your charging system checked out if it's doing this frequently. How old are the alternator and battery? Could also be the voltage regulator on the alternator as well. Much less expensive than the actual alternator and probably easier to replace. I had a '66 Chrysler with lights that would dim and flicker. Swapped the regulator and problem solved!

[Nomadic]

I had the same symptoms when my alternator was on its way out. My understanding is that the battery light goes on when if the alternator is not producing more voltage than the battery. Why ALL the warning lights come on instead of just the battery light is a bit of a mystery. It was a changing issue in my case. Make sure you check the alternator ground-strap.

[AV325i]

Thanks to the advice! I also noticed that the blower motor speed Increases when the 3 lights come on. That would suggest to me the voltage is going up which does not make sense. It has stopped happening lately, so I will just see what happens.

[taperunner]

HELP SAME PROBLEM... 1989 325is
this just happened to me a few weeks ago. i swapped the voltage reg, got the alternator bench tested and it still failed. So i got a new alternator as well. The battery was smoked to boot (because i guess the car had been underpowered for some time before everything finally went at once). so to sum up: New Battery, New Voltage Reg, New Alternator. BUT...the Bently says at 1500 RPM with all accessories turned off the battery should read between 13.5 and 14.2. At rest my battery sits at 12.4 and running it stands about 11.9 to 12.0 (at idle, at 1500, at 2000, at 2500). then when the car is turned off it charges back to 12.38 or 12.4. I've tried taking it for a bit of a drive and it doesn't change much, goes down slightly in charge. but the voltage doesn't seem to be getting back to the battery.

what does anyone recommend the best way to start eliminating causes?

thanks