No brake lights

[pernest]

Drive thru deep road water in traffic — enough to completely drown the brake light switches. My brake cylinder pressure is probably not optimal but does provide enough pedal to brake easily.

I can easily replace the stitches but remember hearing that sometimes faulty master brake cylinder pressure can affect the circuit. Is there a way to test for this?

[jinx758]

Simple test light should work.
Point on terminal wire/switch tab & clip grounded.
Key on & press brake, both if dual circuit but should be redundant.

I'd make a test light from speaker wire & a bulb then set bulb on frunk hood - my wife rolls her eyes sometimes when I ask.

Good luck ... stay safe

jinx
_________________
" It's not valuable unless you learn something from an experience. " Henry Ford

It's not unlike the same difference ...

My Craigslist rescued 100 footer :
1971 Standard Bug
1776cc dual port
034 distributor
38mm EGAS Carburetor

[Cusser]

3-minute diagnosis.

Of course you didn't state what year......

_________________
1970 VW (owned since 1972) and 1971 VW Convertible (owned since 1976), second owner of each. The '71 now has the 1835 engine, swapped from the '70. Second owner of each. 1988 Mazda B2200 truck, 1998 Frontier, 2014 Yukon, 2004 Frontier King Cab. All manual transmission except for the Yukon. http://www.thesamba.com/vw/forum/album_page.php?pic_id=335294 http://www.thesamba.com/vw/forum/album_page.php?pic_id=335297

[pernest]

It’s a 1973 std. Each switch has 3 prongs — test each one with the light, ignition on, brake pedal pushed? Does fluid pressure in the master cylinder have anything to do with the continuity?

[Cusser]

[runamoc]

I installed this in the trunk for troubleshooting brake lights/switches. I can check for voltage coming from the switches with a VOM or apply voltage with a jumper to 'force' the brake lights on.

Use this 'affordable' clamp from HF to depress the brake pedal against the seat when no help is around.

https://www.harborfreight.com/36-in-ratcheting-bar-clampspreader-64152.html
_________________
Daily driver: '69 Baja owned 45 yrs - Plan B: '72 Ghia
Yard Art: 2 Sandrails
Outback: '69 Ghia - '68,'69,'70,'72 Beetle - '84 Scirocco, GTI - Pair of '02 Golfs- '80 Rabbit Diesel
VW Wiring = It's just wires

[pernest]

Connected the two parallel spades with ignition turned on — no brake light. Blinkers work so fuse must be okay. Will check to see if brake light connection somehow became disconnected from fuse box connection but I think it’s still connected.

So if the light doesn’t work even when the parallel switch spades are connected, what else should I consider?

[runamoc]

[Cusser]

[pernest]

I don’t thing it’s a burned out taillight bulb — normally one would work. Car has a three bulb assembly. The middle bulb is two filament and works with the lights switched on. I don’t think the master cylinder is involved because even when the two I parallel spades are connected, there is still no light. I could not find a correct diagram for the 1973 std beetle three bulb taillight assembly so I’m assuming it’s the middle bulb.

[jinx758]

We assume they worked before this puddle.

Things I'd check :

Clean grounds, water can get between screw/washer & metal if not clean, shiny, & tight to begin with. Also scrape pin on bulb & recessed U-cup where pin rests in holder housing.

Jumper wire from known hot to + of bulb.

If brakes used while in puddle - chance the wire/terminal connection shorted the switches as it mite be exposed if the rubber terminal boots are torn/missing.

"I don't think it's a burned out bulb".
You won't ever know until you test. Rule this out.
All we can do is make suggestions, it's up to you to verify a
PASS or FAIL.

Good luck ... stay safe

jinx
_________________
" It's not valuable unless you learn something from an experience. " Henry Ford

It's not unlike the same difference ...

My Craigslist rescued 100 footer :
1971 Standard Bug
1776cc dual port
034 distributor
38mm EGAS Carburetor

[Cusser]

[pernest]

Jinx

Yes, the boots around the switch were totally missing exposing the connections to water. I somehow got thru water at least 12 inches deep. The street is notorious for water retention and I had to use it to make an important medical appointment.

I verified cionductivity connecting the parallel wires. Will get a switch tomorrow and install. Thank you (and the others) for verifying my suspicions that the water experience might be the culprit.