Passenger side headlight not working

[Sporgle]

I've got a 69 stock seen some years but overall good condition. I've got a problem with my passenger side headlight not lighting up. I've tested the bulb and it tested good in the driver side.

I did test with a voltmeter on the connector itself there are three wires inside of it a yellow a white and a brown or red but it's faded. All combinations yield the same voltage of around 11.9 to 12 with the engine off and just the battery except for yellow and brown which reads only about .2 volts.

I'm not very familiar with the electronics in this car so I'm kind of stumped is there a wiring issue or maybe a connector is bad is that the correct readouts for those wires? any help greatly appreciated thank you!

[Sporgle]

I forgot to mention, when the bulb is in and lights turned on all connectors read 0 volts. But only when the light is plugged in.

[KTPhil]

Check/spin fuses.
Check your wires against this diagram below.

White is high beam, yellow is low beam. Brown is ground.
_________________
Current Fleet:
- '71 Fastback
- '69 Westfalia
Retired:
- '67 Beetle
- '65 Beetle (x2)
- '65 Bus
- '71 Squareback

[my3bugs]

likely the ground connection . in my 70 there in the front trunk by the gas tank , left n right .

[Sporgle]

Checked and cleaned ground, checked and cleaned fuses. No dice.

The only electric work I've done is the turn signal switch. Could this cause any issues?

As extra info my low beams have never worked the switch is probably bad or something and the hazard switch is touchy and will cause the turn signals to not function if it isn't screwed in all the way. This car is a little of an electrical nightmare inherited from my grandfather who never replaced only repaired to good enough lol.

[ashman40]

When you say the bulb tested good when installed on the driver's side... did you test both HI and LOW beam function?

FYI, HI beam power comes over WHITE wires. LOW beam power is YELLOW wires. If your passenger side headlight plug has 0.2v on the yellow wire and 12v on the white wire it suggests your HIGH beams are ON and not your LOWs. The BROWN wire in the plug is a ground wire.
Power for the headlights comes from the headlight switch over the white/black wire to the headlight dimmer relay. The dimmer relay is a latching relay. This means it "latches" to an output path until the relay is next momentarily powered and then it "latches" to a different output path. This means the relay is powering either its LOW (yellow) wire or HI (white) wire output. Each wire from the dimmer relay should connect to the side of the fuse box where a brass bar is connecting a pair of fuses together. This allows a single wire to power a pair of fuses. The yellow wire from the relay powers fuses #5 & #6. The white wire powers fuses #3 & #4.


Rerun your test:

Turn the Headlight switch ON to the 2nd position (headlights and parking lights ON).
With one probe of your tester grounded to a "known good ground" (ground screw or fuel tank bolt?), test the white and yellow wires at the headlight plug. Only one wire at a time will read 12v.
Go to the wire side of your fuse box in the trunk. Fuses #3~#6 are your headlight fuses (#3 is 3rd from the right edge as viewed from the trunk side of the fuse box). If wired as shown above, fuses #3 & #4 will have white HIGH beam wires. Fuses #5 & #6 will have YELLOW. Test the pair of fuses here at the fuse box. Test both ends of the fuses to confirm power is flowing thru the fuse. Depending which colored wire at the plug was powered, test the corresponding two fuses here connected to the same wire color.
Next, pull on the turn signal lever to activate the dimmer switch. This should cause the dimmer relay to click and change its output.
Go back and test the white and yellow wires at the headlight plug. Power should have switched to the other colored wire. Also test that the pair of fuses for the same color wires are now powered at the fuse box.
This confirms you headlight dimmer switch and relay are working and powering the proper pair of fuses and wiring all the way to the headlight plug.
Lastly, retest for power on the WHITE and YELLOW wires at the headlight plug like you did above, but move the ground connection from the known good ground to the brown wire in the headlight plug. The headlamp itself using this brown wire for its ground. You should get the same voltage reading.

See below Speedy Jim's diagram on headlight wiring. Note how the headlight plug is wired. Confirm your wiring matches this diagram.

Above, you would imagine that the opposing wires would be the power wires and the different wire would be the ground. This is not how the plug is wired. If your plug is incorectly wired you can remove the wires from the plug and reinsert them in the correct position. You may need a small jeweler's screwsdriver to compress the locking clip of the brass terminal to free it and it will pull free from the plug. It helps to bend this clip outward slightly before reinserting it.
_________________
AshMan40
---------------------------
'67 Beetle #1 {project car that never made it to the road }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!}

[Sporgle]

Alrighty I'll give that a shot, I know for sure low beams don't work at all for either side it's a problem it's had for a while I assume due to the switch or relay.

Another person said it could be grounded out somewhere because once the circuit completes when the bulb is in I get no voltage at all on any wire going to the headlight. But I'll give the tests a shot and let you know, thanks!

[Cusser]

[my3bugs]

well , the high / low beam is in the turn signal switch here . so it just might have something to do with it , like if it cant complete cirquit ......does your high low switch do anything ????

lift towards you on the turn signal lever ?

you have to be pretty precise playing with wires . some new modern repo switches the wire codes arent as easy to color code . a few wires were like the wrong color or had no stripe i forget but i figured it out as i just put in one of these switches recently . ya your headlights go thru there ..........

just saying in a 70 the turn signals all run thru the emergency flasher switch , that was fun to figure out .

[VW_Jimbo]

X2 with rolling the fuses.

Turn the key on. Turn the headlights on. Then roll the fuses. They will most likely spark a little bit while you roll them in their holders!
_________________
Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[Sporgle]

High beams work for driver side and passenger side until passenger side gave out, and the dimmer for the dash light works, bulb is out but I know the dash works. Low beams don't work on either side.

[jinx758]

Use a multimeter & check wires for continuity without power.

Jam a piece of paperclip into wire. Run from battery to inside of headlight plug on yellow then white wire. This will bypass switch. Careful with this test as will not tolerate being grounded at anytime.

A few months ago my headlight switch separated from its metal housing. Used a zip tie to get me home. Still functional to this day.

Redneck troubleshooting at its laziest - always think outside the box.

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

[ashman40]

[Cusser]

Electrical stuff is tough to "fix" long distance.

For someone like Ashman, myself, or many others on this forum, this would be under 15 minutes to diagnose if we were with the vehicle. Bring it to Arizona, The Cuss will fix !
_________________
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