First time owner, electrical gremlins

[daceto817]

Hi Bimmerforums!

So this is about two issues that have been happening that seem to be connected, I'll describe two specific events that have occurred and the symptoms.

First one happened about a week ago. I was driving on the highway at 80 mph or so, smooth road, no rain, nothing out of the ordinary. A few things happened at once: the radio cut out and came back, a couple warning lights on the dash flashed including the stability control light, and the car stuttered like it came out of gear for a second. The transmission light stayed on, so I pulled off the next exit. The car drove the few miles to the exit fine, but once I stopped at the light on the off ramp, it wouldn't start going again until I shifted it into 1st (I have an auto so it wouldn't go while in D). Pulled into a gas station and turned it off for a minute, then turned it back on and went home.

Second one happened about an hour ago. I was sitting in traffic on the way home, and earlier I had noticed that the radio and dash lights were flickering, the brightness going up and down intermittently. Traffic started to move so I accelerated and the same thing happened as it did in the first occurrence: radio cut out, a bunch of warning lights came on, but this time the jerk was much more noticeable and abrupt. It freaked me out, this time the warning lights all went out but the dash continued to flicker for a few minutes.

Any thoughts? I'm about to take the passenger seat out to check for water damage, but I wanted to ask here to see if I could narrow down what needs to be checked and/or replaced. I also plan on getting a code reader as soon as I can.

[TheAngryBear]

Check your alternator voltage, battery voltage, and grounds.


2001 750iL DD74441
Stock

RIP: 2003 540iA Sport GS56111
H&R front springs, Ultimate Cup Holder, Euro Dash & Armrest, Grom, BavSound Stage1

[daceto817]

The grounds in the engine bay are solid, should I undo them and clean them as well? Where else would I find grounds that should be checked? I've had the battery and alternator checked in the past and they were good, but that was a few weeks ago so it could've changed.

[TheAngryBear]

Check your battery grounds in the trunk and ensure the clamps are tight on the posts.

As for the engine grounds: visible corrosion/dirt/grime? Pull and clean. Otherwise just ensure they are tight.

Voltage is always a good thing to check. These vehicles are very sensitive to low voltage.


2001 750iL DD74441
Stock

RIP: 2003 540iA Sport GS56111
H&R front springs, Ultimate Cup Holder, Euro Dash & Armrest, Grom, BavSound Stage1

[JimLev]

Could also be the ignition switch too.

[daceto817]

Update, went to get the voltage tested and apparently the voltage regulator is toast. Guess I'll add the alternator to the list of things that need replacing. Thanks for the help!

[JimLev]

Update, went to get the voltage tested and apparently the voltage regulator is toast. Guess I'll add the alternator to the list of things that need replacing. Thanks for the help!

Wasnt your battery light on?