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Posted by: Ampex351 Jun 11 2020, 09:14 PM

The big red light light on the dash was on ALL the time. Very annoying. OK...found the master cylinder (new from P.O.) nothing wrong. Bled the brakes, all calipers rebuilt. Red light STAYS on. Removed the wire from master cylinder and tested the circuit. The switch in the master is BAD. Can these be purchased? Where?

Thanks!

Posted by: jvmarino Jun 11 2020, 09:17 PM

I believe there is a manual reset button on the switch. If the switch gets activated due to a circuit imbalance, this switch needs to be pressed in the reset the switch. It is a plastic post behind the wire tab. I tried to attach a picture I saw on another recent post.

Posted by: Ampex351 Jun 11 2020, 09:22 PM

QUOTE(jvmarino @ Jun 11 2020, 10:17 PM)

I believe there is a manual reset button on the switch. If the switch gets activated due to a circuit imbalance, this switch needs to be pressed in the reset the switch. It think it looks like a plastic post between the wire tabs.

It won't reset. It's stuck open and will not respond. I just saw on Auto Atlanta
they sell replacements. If I go that route and take out the faulty switch and replace it will brake fluid leak out while I'm doing the change over?

Posted by: jvmarino Jun 11 2020, 09:28 PM

It has been a long time since I messed with the master cylinder, but I do believe fluid will come out. It shouldn’t be high flow as the system will have no pressure on it and the reservoir cap should prevent much gravity flow. You will likely need to bleed it afterward.

Posted by: framos914 Jun 11 2020, 10:27 PM

Did the red light turn off when you pulled the wire off the Master Cylinder? If the light went out, that's a sure way of knowing your reset switch is defective.
The emergency brake uses the same light.

Posted by: Ampex351 Jun 12 2020, 12:52 PM

QUOTE(framos914 @ Jun 11 2020, 11:27 PM)

Did the red light turn off when you pulled the wire off the Master Cylinder? If the light went out, that's a sure way of knowing your reset switch is defective.
The emergency brake uses the same light.

Yes....we pulled the wire off of the switch, light on dash went out and the light still works when e-brake is set. Not to be offensive to anyone BUT I think you'd have to be pretty dense to not realize something is wrong with your brakes when you need to depend on a red,light to tell you. The car will let you know something's up.
For now Im just going to leave the switch wire off.

Posted by: Mikey914 Jun 12 2020, 01:18 PM

I've got the ones we use for ours Hows $6+ shipping Reg domestic would be cheap. Only problem is they are 1 pole meaning the negative is off the body. I have a 2 pole ATE in box fro $35 if you want it. Just PM me

Posted by: 914werke Jul 28 2020, 11:27 AM

QUOTE(jvmarino @ Jun 11 2020, 08:17 PM)

I believe there is a manual reset button on the switch.

On the early (two pole) switch there is no reset

Posted by: dr914@autoatlanta.com Jul 28 2020, 12:05 PM

yes all three varieties are available

QUOTE(Ampex351 @ Jun 11 2020, 08:14 PM)