What does this &@#*! light mean?

Raul · 12-02-2002, 11:03 AM

My 72 911T has the optional large combined "Oil Temperature/Pressure Gauge" At the top of this gauge is a light and below it is some funny symbol like a hand brake maybe. Below that it says "OIL". Yesterday after I swapped out the rear brake pads and then started up my 911 this light started to flash, (brakes work fine.) just like a blinker, I can even hear it flash. My oil pressure is fine and oil level is ok also oil is being pumped through the oil tank. The drivers manual talks about this gauge but not a word about the light. What does this light mean? Also, what does VDO stand for?

k9handler · 11:25 AM

it's the E-Brake light...
and can be adjusted to match your new brake pads...
instructions can be found in the Haynes repair manual (pg 188 #17)

Here is what it says...

Pull up the tunnel cover and handbrake lever boot, then raise the handbrake lever by one notch of the ratchet.

Loosen the single screw and reposition the switch contact block, if necessary, so that the warning light just comes on.

I had this happen about 8 months ago and this procedure worked.

Wayne 962 · Wayne 962's Garage

I believe it also doubles for a brake failure light on that year car. Sounds like you may have to bleed your system...

-Wayne

k9handler · 12-02-2002, 11:59 AM

I also should have mentioned that...thanks Wayne, I missed that one.

Raul · 12-02-2002, 03:07 PM

Thanks for the good info. Now it makes sense. I'll check both out. I misunderstood when Porsche put "OIL" right under the light.

Tyson Schmidt · 12-02-2002, 10:08 PM

Actually it really has nothing to do with the handbrake. That is a separate drum system. The light doubles as a brake pressure warning light, as Wayne said.
What likely happened is that the pressure differential switch on the side of the master cylinder was triggered while you were pumping the brakes back up after the new pad install.
It will likely require disconnecting the battery (Both ground straps at the same time on your particular car.) to reset the light to stop the blinking.

billwagnon · 12-03-2002, 10:12 AM

If I recall correctly, after I replaced my master cylinder mine did that. There is a button on the master cylinder that you push to reset the light.

Raul · 12-06-2002, 11:28 AM

I tried disconnecting both batteries and that did not work. How do I get to the brake's master cylinder?

jeff m · 12-06-2002, 12:42 PM

The sensor on the MS is accessable from under the car, if you pull off the wire you will be able to confirm that flashing light is caused from MS.
Then check that your handbrake still ops the flashing light when on.
But I think just bleeding the brakes will solve your prob.
If not then it's the sensor, If your brakes are good, (only you can decide that) you could remove wire from sensor under car. that will stop that annoying light. Then you will not have to drive with one hand at 12 o'clock!
jeff
911T

Tyson Schmidt · 12-07-2002, 09:07 AM

Actually Bill Wagnon is right. There's a reset button on the pressure differential switch on the side of the master cylinder. I didn't think the early master cylinders with the 2-wire switches had this feature, but apparently they do.
It's a little white plastic pill-shaped button sticking out of the center of the switch. Push it in to reset.

billwagnon · 12-07-2002, 05:43 PM

Here's the sequence (not including up/down with the jack):

remove wheels
remove belly pan
replace master cylinder (fun fun fun!)
bleed brakes (more fun)
put belly pan on
put wheels on (woohoo almost done!)
get in car for brake test, notice flashing light
scratch noggin...research research research
remove belly pan
push the pill-shaped button
replace belly pan

believe it or not ALL of my projects go this way!

Raul · 12-09-2002, 02:36 PM

Thanks guys. I removed the pan and found the button (the button was a tiny thing). Now the light doesn't blink ... at all, not even with the e brake on. But then I don't think the light ever came on with the e brake on. Now I guess I'll have to find the e brake switch and adjust it.

Is everything with the Porsche engineered so oddly? Not that it is engineered poorly just differently. Why can't things be easy to get at and work on.