01' 996 ABS light problem

[biomech]

Hi Folks,

New to the forum and also a new owner of a used 01' 996 C2. I've had the 996 for about a month and love driving it! But, in the recent few days, I've had both the ABS light and PSM off light come on while driving. Both lights reset every time I turn the ignition off but, they usually come back on after 5 to 10 miles of driving, and normally always while on the freeway.

I hoping I can do some diagnostic at home before bringing it to my mechanic. Any help is greatly appreciated.

[Loren]

A faulty brake light switch or a bad MAF sensor will generate ABS/PSM failure (both lights at the same time) on a C2.

Those are the most common causes. Have someone stand behind your car and see if the brake lights work - if they do you can rule out the brake switch.

[zegypt]

A faulty brake light switch or a bad MAF sensor will generate ABS/PSM failure (both lights at the same time) on a C2.

Those are the most common causes. Have someone stand behind your car and see if the brake lights work - if they do you can rule out the brake switch.

Loren.....is this true for a 2002 C2 as well?

[Loren]

A faulty brake light switch or a bad MAF sensor will generate ABS/PSM failure (both lights at the same time) on a C2.

Those are the most common causes. Have someone stand behind your car and see if the brake lights work - if they do you can rule out the brake switch.

Loren.....is this true for a 2002 C2 as well?

Yes, it can.

[zegypt]

Loren - I think you're right. My right brake light is out (but the left brake light is working). Can you tell me where the brake light switch is located and explain how to replace it? I assume it is the switch under the brake pedal.

Lastly, can it be that one of my brake lights is simply out or does it have to be the brake light switch?

[Loren]

Loren - I think you're right. My right brake light is out (but the left brake light is working). Can you tell me where the brake light switch is located and explain how to replace it? I assume it is the switch under the brake pedal.

Lastly, can it be that one of my brake lights is simply out or does it have to be the brake light switch?

Removal

Release by turning 90°, and pull out of the installation opening.

Installation

Reverse of above. When installing the switch for the first time, it is essential to press it vertically against the bearing surface. It will otherwise not be possible to lock the switch (90° turn), even if great force is exerted.

Adjust if needed.

The pedal must move a perceptible distance of approx. 5 to 10 mm before the brake light lights up.

At the same time, check (make sure) that the brake light lights up before the pedal meets perceptible resistance or before brake pressure builds up.

[zegypt]

That did the trick.

Thanks, Loren. Your help is greatly appreciated!