TheSamba.com :: View topic

Fri Jun 09, 2017 9:11 pm

73 -- Brake warning light is always on, unless I press the brake, then it turns off. Wiring appears correct, looking for ideas on how to trouble shoot.

Wed Jun 14, 2017 10:05 am

I've waited days to reply to this hoping that someone more knowledgeable would chime in. My understanding of the brake light switches is not crystal clear.

If I understand correctly, there are two ways that the brake warning lamp may be lit. The first of course is by means of one of the brake lamp switches. The second is by means of a blue wire with the brake warning lamp on one end and the voltage regulator at the other. In this second case, the voltage regulator sends voltage to the brake warning lamp when the key switch is on but the engine is off. This is for the purpose of a bulb check.

So, as far as trouble shooting goes, first I would see if while the engine is running the blue wire is energized. That would indicate a fault in the voltage regulator.

If it is not energized, then the fault may be in one of the brake lamp switches. Unplug each one in turn to see if the warning lamp goes out to identify which is bad. Take note of which wire goes where beforehand.

Hope that helps.

Maybe someone could explain the function of the red and black wires as they relate to the brake warning lamp. There seems to be one always hot wire, two sometimes hot wires, and a ground at the lamp, and I'm unsure of how they work.

Wed Jun 14, 2017 6:53 pm

Thanks. I.l give it ater and report back

Thu Jun 15, 2017 7:29 am

My brake warning light has not worked since I got my car, and maybe it's time it should. What suggestions does the collective have on checking/making this happen? I just replaced both switches, so that shouldn't be the problem./

Thu Jun 15, 2017 7:36 am

I had the same issue. I found out that the original master cylinder brake sensors with 3 prongs that the Thing mounted originally do not exist anymore.

So you can-t build the correct circuit needed for the light to work properly.

Thu Jun 15, 2017 10:01 am

perello wrote: … I found out that the original master cylinder brake sensors with 3 prongs that the Thing mounted originally do not exist anymore. So you can-t build the correct circuit needed for the light to work properly.

Don't exist anymore? They are ubiquitous. Search the part number: 113945515G

Thu Sep 02, 2021 9:02 pm

Does anyone have any guidance or pictures showing how you ran the wiring for these lights? Thanks!!

Fri Sep 03, 2021 8:15 am

When I put my Thing back together from the restoration I had the exact same problem. I found that I had the wires swapped on terminals K and 61 on the warning light (dang small terminal numbers...). Landed the wires properly and the light works perfectly.

The lettering on the warning light is really small and my eyes aren't what they used to be... Suggest you double check (with a magnifying glass if needed) the markings on the terminals on the brake light and make sure that the wiring is correct.

I hope that helps.