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low beam and high beam light

2K views 4 replies 3 participants last post by  ianrandom 
#1 ·
hello
last night my 1987 w126 SE did not switch from low to high beam light when I push the lever, low beam is off and no high beam is ON ,
I tray several time to switch some times it did ON but mostly it didnt.
I have checked the fuse its ok,
is that a relay issue (if there is one) where it is located, or it is a lever problem ....?

many thanks.....:eek:
 
#2 ·
Im having trouble understanding your wording. So, your high beams didnt come on, only your low beams. but then your low beams turned off and you had no lights? Or your switch did work and turned them on? Now they switch over only sometimes?

Sounds like a bad lever to me, but Im not sure that I understand everything.
 
#4 ·
OK, this is just blind brainstorming here, so bare with me if I am wrong, but since no one else is helping, I figure i will give it a shot.

Im not so sure that headlamps have a relay, do they? A relay changes the power direction of what it is connected to. Headlamps have a single power, either on or off. Our directionals have a relay because it is realying the power on and off in a uniform fasion. And the fogs will, because they turn off when the high beams are turned on. That makes sense, yeah?

Our headlamp highs and lows are always powered, its just that they are connected when the switch is turned on. If the fuse looks good, and has proper voltage then it wouldnt be a short, it must be not getting power. We only have one ground to the headlamps, so it is not that.

So if the fuse is good and there is power going to the highbeam wire at the headlamp itself, then it must be the microswitch located in the stalk that is malfuntioning..... at least that is what it seems like it would be to me.


If I am totally off track, dont be afraid to school me on how I am wrong, like I said, this is all just blind brainstorming.
 
#5 ·
I think there is a relay in the fusebox or near it. The longer one amongst the others if your car is similar. I'd say that was the likely culprit.The switches are pretty hard to break, but its possible i guess.

I recently fixed a bad contact in the switch by careful cleaning with switch cleaner and cotton wool buds. That was the indicators not working properly though.

When checking the fuses there is the standard warning that they can look ok but not be due to the aluminium type not being ideal.
 
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