Carreralund

I've got a -89 Carrera 4.

When I start the Car after it has been undriven for over 12 hours or so, the warning lights for the brake fluid level and the PDAS is always on and after a while the alarm buzzer goes off and sounds for about 5 beeps or so.

After this all the lights come off and It's working normally.

Someone got an ide what my problem is or is this normal, and for how long should these warning light be on after starting the car?

___________
Andrew
Carrera 4
Oslo, Norway

Adrian

Dear Andrew,
The most common causes of this are
1/. Bad battery
2/. Old brake fluid
3/. You have some air in the system
4/. The pressure switch is slow to operate as the pressure builds

It is just annoying there is nothing wrong with your C4 just that the pressure is taking a little longer to build up than normal. Most common cause is the battery or the charge circuit not keeping the battery fully charged.

Ciao,
Adrian
964C4

Carl Muckenhirn

Andrew,

I've had similar situation for the last year. (Slow to turn off after cold starts)

Over the last 2 months I started getting intermittent illumination of the PDAS and Brake Fluid lights while driving. Finally lost all boost. I'm replacing the pressure switch now.

You may want to be prepared for it. I've also got an 89 C4 just at 100K miles.

carl.

Carreralund

This weekend the ABS warning light also started to light after cold starts. It stays on together with the PDAS warning light for about 2-3 minutes. Anyone with any tips to handle this?

Carl Muckenhirn

Andrew,

Are you sure it's the ABS warning light (9 in the picture) and not the brake pressure light (13)?

I've had intermittent ABS/PDAS lights that was traced to bad spark plug wires (arcing in the engine compartment interfered with the ABS sensors).

The PDAS and Pressure warning are probably related to the hydralic pressure switch mentioned above.

carl.

Carreralund

Yepp, ABS (9) and PDAS (8) stays on for about 2-3 minutes, sometimes longer. At cold starts also brake pressure (13) stays on untill the alarm goes off and sometimes even longer.

Andrew

Carreralund

Yesterday i lost power to the headlights lights and the Stereo shut down.
(Headlights automatically turns on when car is running, this is gouverned by law in Norway). It seems to me that it cut's power to surtain functions if the ABS and PDAS warning lights stays on.

It all came back on when the ABS and PDAS warning lights went of.

Youcef

Hmmm, this sounds very familiar to a problem I had with the ignition switch. When my ignition switch was worn (there is a thread called "Windows/Headlights/A/C Fan dead"). I had the similar symtoms where the brake pump would not activate along with lights etc. Might be worth a try to jiggle the keys while the lights are on and listen for the pump to activate, you can usually hear it best without engine running.

Youcef

Carreralund

"This weekend the ABS warning light also started to light after cold starts. It stays on together with the PDAS warning light for about 2-3 minutes. Anyone with any tips to handle this?"

Answer:

Have just changed the battery and this problem does no longer excist I'm also changing the "current regulater" (lack of better word in english) and this will probably solve first problem

Andy Roe

Andrew,

Glad to hear you've got the problem fixed. Sounds similar to a problem I had in my old C4 that was caused by a faulty "voltage regulator" on the alternator. I changed that & my battery and was all fixed!!

Andy