QuestionThe brake pressure light on the dash blinks on and off all the time even after replacing the master cylinder and the 2 switches on it. Is there a way to reset it it or is the problem somewhere else, Thanks, Marc.
AnswerMarc,
Just to remind you, my expertise lies in the older 356 models. Luckily, many early designs/concepts have lasted since the early 50's and appear in revised forms on 911's, 914's 944's, Boxsters, etc. Where this happens I'll promise to try to give you the best answer I can.
Also, I've done some work on 944's so I have a reference manual handy. As for the 928's, about the only time I see them is whizzing past me at about 85 mph. Unfortuantely, there's no reference in my manusl to a brake pressure warning light. But there is an interesting note in the brake bleeding section. The clutch, for 944's, and perhaps 928's as well, shares the same hydraulic fluid with the brakes. So this means the clutch would have to be bled when the brake system has been opened up.
If that is not causing the warning, then the only other legitimate reason would be low pressure at a wheel cylinder, like because of a leak...but you should be able to see seepage at least.
I don't know how you can reset that light if it turns out it's a faulty signal. All I can suggest is to check a wiring diagram to see where the pressure sensor is located, remove and then reinstall its electrical connections, and hope that works. Good luck.
Dave
