mpuldy

I just purchased a '96 911 4S, and i notice many times when I am driving the car and stop at a red-light, the ABD *Automatic Brake Differential' green light on the instrument gauge turns on. The light remains on until I start moving again and then the light goes off.

Any suggestions on what's going on?

Gbos1

Bad ABD / ABS Relays is most likely. Try cleaning them the contact blades there are 3.

Speed Sensors may need cleaned or replaced as well.

mpuldy

excellent suggestion! will try that in a few weeks when i have my next opportunity to work on the car...thank you!

993.Coupe

I had to replace both of mine recently (C2 only has 2, cleaning them didn't work) and getting the relay 'box' off is much easier with the help of some pictures:

https://rennlist.com/forums/993-foru...n-today-4.html

O'Reilys relays have been working great for me and readily available....