brake warning light

I have a '72 standard Beetle. In my quest to get EVERYTHING functioning properly in this car I am down to one last small item. and it is driving me nuts.

How is the brake warning light suppose to work? Other than the obvious "comes on when the brakes mess up".

I have heard that you are supposed to be able to test the light by pushing on the lens(?) I would guess that it would have a slight 'spring' to the lens in order for it to operate like that. Mine has no 'spring'. pushing on the light does nothing, the lens doesn't move in, nothing lights up. How do I remove it?

Thanks,

Dave

Reply to
john
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Your year has no push-to-test. It automatically tests itself when the key is turned to ON.

This is what the inside of the warning light looks like:

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This is what the wiring scheme for the 2 brake switches looks like:
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Red wire goes to term "K" on the warning light. More elec "stuff" on my web site:

Reply to
Speedy Jim

Up thru '71 the lens pushed in to test the bulb. Starting in '72 that light is supposed to come on, along with the generator and oil light, when you turn the key on, but the engine hasn't started.

Unfortunately, a lot of the solid state works in these late units have died. If you're good with small electronics you can fix it, but it might be easier to find a good used one. I'm sure I have several of these here.

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----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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Reply to
Jim Adney

After some more troubleshooting I have some new news. I am getting power at the light, but the light isn't burning. There is a relay that two of the wires coming out of the light go to. How do I check the relay?

Thanks,

Dave

Reply to
john

O.K. after some hours out with the Voltmeter I have some new questions. I don't think the light is the culprit. From what I understand from the diagrams I have been studying, the warning light should take it's test power from the oil light located in the speedo.

There is a blue wire that comes up from the abyss that is the inner fender well on the drivers side. This wire then runs through what looks to be a fusible link. Two blue wires then emerge from the other side of this link. One goes to the oil light, one to the brake warning light.

I just don't get this. I get power to one side of the warning light, but no light. I picked up two bulbs while I was out today and neither one works. I cleaned off the ground lug and the connector and still get nothing.

Is this system in any way connected to the door switch/ignition buzzer? That is actually the last part of my electrical repairs. I forgot about that one. I just haven't been able to find a replacement switch.

Thanks,

Dave

Reply to
john

Yes.

Yes.

This wire then runs through what looks to be a

No.

Two blue wires then emerge from the other side of this link.

Yes.

No.

I posted links to these 2 drawings last time. Maybe my posts are being filtered out?

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Term #61 goes "Low" when the OIL light is On. Term #15 is live with key On. If the light does not light under those conditions, then the internal ckt (transistor) is bad.

Reply to
Speedy Jim

When the late, non-pushbutton, warning lights stop working, It's generally because there's a dead transistor inside the light assembly itself. You can take them apart and replace the transistor if you are familiar with this kind of stuff.

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----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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Reply to
Jim Adney

It appears that I am not getting a ground with the light socket. I can ground a tester to the gear shift and check inside the socket with the bulb removed and I get power, but with the tester on the ground lead and the hot side of the light I get nothing. I'll just keep working with it. It is really hard to see where everything connects from the back of the light because the wiper assembly is directly in the way.

I actually have a degree in electronics, but that was 15 years ago and I never put it into use so most of it has been forgotten.

Thanks,

Dave

Reply to
john

Do you have the Bentley manual for your car? Sounds like you don't, because most of your questions are answered in the wiring diagrams there. Get one; it will be one of the best investments you'll ever make.

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----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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Reply to
Jim Adney

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