Headlight problems - mainbeam weirdness
Discussion
Its MOT time again so checking the lights and find that they appear to work fine until:
Flash mainbeam and only the passenger side lights up ok but only the drivers side dipped stays on.
Put mainbeam on permanently and the passenger side lights up ok but the drivers side goes from dipped to sidelights only.
I've trawled through the previous posts on light problems and tried all the suggestions but to no avail.
Only thing I can think of is the dip/main relay is faulty somehow, does anyone know what car it is off or a part number for one ? and to make sure I'm checking the correct one is it located in the fuse box or elsewhere.
The car is a 1988 S1.
Any other ideas welcome please.
Flash mainbeam and only the passenger side lights up ok but only the drivers side dipped stays on.
Put mainbeam on permanently and the passenger side lights up ok but the drivers side goes from dipped to sidelights only.
I've trawled through the previous posts on light problems and tried all the suggestions but to no avail.
Only thing I can think of is the dip/main relay is faulty somehow, does anyone know what car it is off or a part number for one ? and to make sure I'm checking the correct one is it located in the fuse box or elsewhere.
The car is a 1988 S1.
Any other ideas welcome please.
Odd.. Most of what fallows is for my S3C. Doubt yours would be any different..
I can't see how the relay would be the problem as the signal from the relay obviously works for the nearside and its the same wire that then leads to to offside, IIRC.
On my car, the 'end' of the wires are at the offside, they then pass along the front of the car joining the wires from the nearside and into the main loom just forward of the washer bottle. If the signal gets to the nearside lamp, it ought to get to the offside lamp unless you havbe a break in the wire somewhere between the nearside and offside lamps. Try taking a line direct from the nearside to offside lamps, mainbeam to mainbeam. If that doesn't work, erm. I'm stuck.
Unless its your bulb.
You've checked that already haven't you?
I can't see how the relay would be the problem as the signal from the relay obviously works for the nearside and its the same wire that then leads to to offside, IIRC.
On my car, the 'end' of the wires are at the offside, they then pass along the front of the car joining the wires from the nearside and into the main loom just forward of the washer bottle. If the signal gets to the nearside lamp, it ought to get to the offside lamp unless you havbe a break in the wire somewhere between the nearside and offside lamps. Try taking a line direct from the nearside to offside lamps, mainbeam to mainbeam. If that doesn't work, erm. I'm stuck.
Unless its your bulb.
You've checked that already haven't you? Sounds like there is a break in the main beam supply to the driver's side. When you use the head lamp flash it brings in high beam in addition to anything else that was switched on. If you switch high beam on permanently then this switches off the dipped beam, leaving just the sidelight on the side with the fault.
Sounds like a simple wiring fault, and if I were you I'd start by checking out the wiring connector down by the bonnet hinge on the side with the fault. They're interior grade connectors ideally placed to pick up spray from the front wheels and they just aren't up to it. As a short term fix you can cut the faulty connector out of the plug and fit a seperate bullet connector, but if you've got time it is worth replacing the connector with proper waterproof connectors. I recommend SureSeal connectors if you take this route.
Sounds like a simple wiring fault, and if I were you I'd start by checking out the wiring connector down by the bonnet hinge on the side with the fault. They're interior grade connectors ideally placed to pick up spray from the front wheels and they just aren't up to it. As a short term fix you can cut the faulty connector out of the plug and fit a seperate bullet connector, but if you've got time it is worth replacing the connector with proper waterproof connectors. I recommend SureSeal connectors if you take this route.
Thanks for the help, all working fine now 
so at least I can't fail the MOT on lights.
It was someting up with the connector, I had checked I was getting power through the female bit and it was ok, fault must have been in the male bit. I've cut it out and directly conected the wires for now and will replace the connector with those mentioned if you can let me know where to get them from.
so at least I can't fail the MOT on lights. It was someting up with the connector, I had checked I was getting power through the female bit and it was ok, fault must have been in the male bit. I've cut it out and directly conected the wires for now and will replace the connector with those mentioned if you can let me know where to get them from.
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