Troubleshooting my electrical issues., My first problem was blinking red light on the dash for brakes Options

[vin man]

Edit: Renamed the thread because what started out as one electrical problem has led to others and I'm hoping to capture all the information in this one thread.

Initial Problem:

When I turn on the 72, the red light on the dash (in the top part of the gauge on the left side of the dash) blinks and won't stop. I've made sure the e-brake is all the way off. I'm wondering where is the switch that controls this light?

I've read that when the brake master cylinder is replaced, there is a switch on the MC that needs to be reset. I used a MC from Rock Auto and there is not reset switch button. Only the electrical switch that activates the brake lights.

I have a brown wire that is connected to nothing in the area of the e-brake handle. I've tried grounding it but the light still blinks on the dash.

Any advice would be appreciated.


Click here for video of the blinking light: Blinking red light

(IMG:http://www.914world.com/bbs2/uploads_offsite/i304.photobucket.com-11380-1486858110.1.jpg)

Master cylinder:
(IMG:http://www.914world.com/bbs2/uploads_offsite/i304.photobucket.com-11380-1486858537.1.jpg)
(IMG:http://www.914world.com/bbs2/uploads_offsite/i304.photobucket.com-11380-1486858538.2.jpg)

[Spoke]

You can pull the bulb out to stop the flashing.

[vin man]

You can pull the bulb out to stop the flashing.

will I still hear the clicking of relay?

[Spoke]

You can pull the bulb out to stop the flashing.

will I still hear the clicking of relay?

The relay will stop flashing when the bulb is removed. See the turnsignal/brake warning schematic below. one of the wires from either the MC switch or the e-brake switch is shorting to chassis. Removing the bulb will break the circuit and the flasher relay will not operate.

This isn't a fix of course because somewhere the wire to the MC switch or e-brake is grounded. When you fix the grounded wire, you can put the bulb back in.

My guess is the brown wire to the e-brake is touching the chassis under the seat or throughout its run to the bulb.

[vin man]

You can pull the bulb out to stop the flashing.

will I still hear the clicking of relay?

The relay will stop flashing when the bulb is removed. See the turnsignal/brake warning schematic below. one of the wires from either the MC switch or the e-brake switch is shorting to chassis. Removing the bulb will break the circuit and the flasher relay will not operate.

This isn't a fix of course because somewhere the wire to the MC switch or e-brake is grounded. When you fix the grounded wire, you can put the bulb back in.

My guess is the brown wire to the e-brake is touching the chassis under the seat or throughout its run to the bulb.

If I do as suggested and remove the bulb, breaking the circuit of the flasher relay - will my turn signals still work? I removed the relay and the turn signals did not work.

I want to fix it properly and find the short, but in the interim, I don't mind pulling the bulb provided I will still have turn signal functionality.

Unfortunately, when it comes to electrical diagrams, I don't comprendo well.

[Spoke]

If I do as suggested and remove the bulb, breaking the circuit of the flasher relay - will my turn signals still work?

Removing the bulb will not affect the turnsignals. Porsche designers had the bright idea to double use the flasher for turnsignals and to flash the brake warning light.

I thought in the first pic the wire to the e-brake switch was disconnected.

[vin man]

If I do as suggested and remove the bulb, breaking the circuit of the flasher relay - will my turn signals still work?

Removing the bulb will not affect the turnsignals. Porsche designers had the bright idea to double use the flasher for turnsignals and to flash the brake warning light.

I thought in the first pic the wire to the e-brake switch was disconnected.

There is a brown wire with white tracer that is disconnected in the area of the e-brake. But I'm not sure if this is the wire that goes to the e-brake switch. I suspect it is since the same color wire is one of the 2 wires on the master cylinder. But I have not yet verified. I was thinking - since that wire is disconnected and the light still blinking, maybe it is not the e-brake wire, but instead a seat belt sensor wire?

I hope to identify the switch tomorrow eve and confirm that a wire is on it.

[vin man]

If I do as suggested and remove the bulb, breaking the circuit of the flasher relay - will my turn signals still work?

Removing the bulb will not affect the turnsignals. Porsche designers had the bright idea to double use the flasher for turnsignals and to flash the brake warning light.

I thought in the first pic the wire to the e-brake switch was disconnected.

There is a brown wire with white tracer that is disconnected in the area of the e-brake. But I'm not sure if this is the wire that goes to the e-brake switch. I suspect it is since the same color wire is one of the 2 wires on the master cylinder. But I have not yet verified. I was thinking - since that wire is disconnected and the light still blinking, maybe it is not the e-brake wire, but instead a seat belt sensor wire?

I hope to identify the switch tomorrow eve and confirm that a wire is on it.

#1 - pulling the bulb is not the answer. While I no longer get a flashing light on the dash, the flasher relay does make a noise. It flashes much faster - almost sounding like a fuel pump.

#2. There is no switch anyplace near the hand brake that I can find.

(IMG:http://www.914world.com/bbs2/uploads_offsite/i304.photobucket.com-11380-1487027916.1.jpg)

(IMG:http://www.914world.com/bbs2/uploads_offsite/i304.photobucket.com-11380-1487027916.2.jpg)

That experiment also didn't work out for the relay. It smoked. Now I need to see if I can find a new one.

Edit: This is the start of problem number 2 - no turn signals or any systems using the flasher.