Payload

My passenger low-beam headlight wouldn't come on for inspection. The high beam on that side works. I checked the voltage at the plug on both sides. These are H4 bulbs. With low beams on I get 12V across the yellow and brown wires on the working (driver's) one, but not the passenger's side one (top and drivers side wires on each connector when installed).

I've eliminated the following causes:
Bad relay - since the driver's side works I think the relay is good.
Bad fuse - Fuses 38 & 39 are both good.
Bad bulb - I swapped the passenger one into the drivers side and it worked.
Bad position sensor in the motor - Not sure if there is a separate sensor for left and right, but since the passenger high beam works, I think this can't be the problem.

Anyone have any idea what else could be causing this?

Thanks in advance,
Matt

Mrmerlin

if the fuse and the bulb are good and your not getting power to the connector,

NOTE try dropping the CE panel to verify that you have power on the rear sides of the fuse holder the fuse may be good,
but the connection in the panel may not be good.

Then the failure is usually under the headlight in the wire harness,
where the harness is crimped to the chassis. .
Remove the wheel,
then the fender liner,
then front block off plate.
Examine the harness with the lights up and down first,

what your looking for is a harness thats been stretched ,
usually in the up position,
gently pull the harness so there is a bigger loop of harness so it wont be stretched in either up or down position.

Then turn on the lights and try moving the harness around to find the break in the wire,
once this is done,
then cut the harness where the wires seem to be damaged and fix the broken wire.
NOTE this will usually be where the crimp was .

michaelathome

Spot on!! I had to remove my headlight cover on my '88 and work the wires back and forth a bit however this was my solution.

Michael

h011yw00d

^^^ +1. Where they crimp the wires to the frame is where the break was for me. I always use this to "wow" people when I'm describing this community. I'm like, "they told me to go there and, holy crap, there it was..."

Stan, you rock, brother...

Mrmerlin

Keep Em Flying !...
Thanks Drew,
Stan

Payload

^ +1.
Thanks Stan for the diagnosis and everyone else for corroboration.

The break was not at the crimp, but still on that section of wire. The yellow wire had parted already and the white was about to go. Spliced in an extra couple inches of wire. This being my first time disassembling the wheel well, the whole job took about 2 hours - could probably get it done in an hour if I had to do it again. I recommend removing the brake duct (1 bolt holds it from inside at the top rear) so you can get both hands in and still see what you're doing. Before and after pics below.

Mrmerlin

from the picture you posted it appears that your bumper shocks are collapsed,
if you can take a picture of the front of your car that shows the fog lamp placement this can be confirmed .
NOTE the fog lamp lens should sit back about 20mm from the front edge of the bumper cover opening.
NOTE it also appears the the headlight washer hose is damaged IE a small hole from getting pinched