[chipwell]

Two weeks ago, I got an SES light with two error codes that indicate failure of the MAF Sensor (4BC2 - Air flow meter signal & 4BC6 - intake frequency to low). At the exact same time, I got two errors for failure of the left daytime running lights, and left brake light. Coincidence? I think not.

I've since replaced the battery (it was in need anyway), and the brake light bulb (just to be sure), and obviously checked all fuses.

So three electrical components go out at the same time. Is there a short somewhere? Is there a way to bench test *just* the MAF sensor to see if it's functioning?

Any help or suggestions greatly appreciated.

[Wilt]

After the battery change, did you clear the error codes and get them again after the battery change?!

[chipwell]

Wilt Yes.

[chipwell]

quick edit: even after replacing the bulbs and clearing codes, the problem continues.

[tdavis42]

Sounds like you have an issue with wiring somewhere after the wires split off to the left side of the car. You should start by looking at a wiring loom diagram and find where the left control bundle splits from the rest and start inspecting from there. It could be due to heat, brittle wires, or somehow getting spliced after getting hit by an object but my bet is on heat.

Here is a diagram of the harness that might be the same as your car. Im not sure of your year or model though.

http://parts.bmwnorthwest.com/a/BMW_...e/61_2886.html

[chipwell]

Thanks, tdavis42 - I will try to start there.