Light problem

Headlights on my mk1 arent working properly. Put the switch on half beam, the lights are on half beam. Put the switch to full beam, and they stay on the half beam. And when I put the high beam on, only one of the lights goes high beam

have you tried replacing the bulbs? check fuses, clean up earth?

Whats half beam?

Half switch, parking lights?

dipped beam ya numpty

Woteva

Ok put new bulbs in, its sorted the full beam out I now have it on both lights

But the half beam is still not coming on, just the sidelights

Don't know what model or year…but you might have dim/dip lights. Apart from the dip beam fuses having blown or the switch being up the swanny, the dimmer resistor might have gone open circuit. It is in the engine bay in the passenger side corner and has two yellow wires. Try joining the wires together and then test the lights. Hope this helps. J.

Its a 1981 Gti, bullet fusebox

I have had a look for the thing with yellow wires and there doesnt seem to be one

Mullet52 said

Ok put new bulbs in, its sorted the full beam out I now have it on both lights

But the half beam is still not coming on, just the sidelights

OK That contradicts what you said earlier because you said "half beam" is sidelights! Use the proper terms for the 3 settings:

sidelights
dipped beam
full/main beam

and then everyone can understand you.

OK, the full beam is now working on both lights

But when switching from sidelights to dipped beam, the sidelights are staying on and I get no dipped beam

Please help!!! MOT in a few days

Had MOT and its obviously failed on the lights, but thats all its failed on

So…..

The sidelights come on ok on the switch, but switch it to half beam and the lights stay on the sidelights

But the full beam works ok

Fuses okay? Getting +12V at the bulb connection okay?

Ye fuses are OK, how do I test if am getting a good 12v at the bulb connection

Am no good with electrics

Put a multimeter on the relevant connection, set on voltmeter, with the other connection on the battery -ve terminal or another good earth.

Would do if I had one :?

Mullet52 said

Would do if I had one :?

Ok I give up - I don't know how to find the fault or fix this without a multimeter - anyone else care to help???

Mr Mullet. Just had a look at the circuit diagram (again). The sidelights are supposed to stay on with the headlights, so that is one plus. From the light switch there is a single feed to the dip switch...as the main beam is working, it confirms that the lightswitch is OK. As the main beam is OK I presume also that the flash facility is also OK. There are two fuses for the dip beam (what you keep calling "half beam" so the problem is narrowed to the dip switch, the fuses or cut wires to the lamps. The later is unlikely as the dip and full beam wires travel together and the chances of both sides being damaged is remote. It looks like the dip switch is U/S, terminal 56b feeds the dip beam...as our friend says it really needs a poke with a meter. Failing that a 12 volt bulb on two wires. stick one on an earth somewhere and the other on the terminal 56B and operate the switch. If it fails to light...the switch is done for. After this its just about impossible to find the fault online....best of luck sir ! J

Terminal 56b? You mean on the fusebox? And by switch do ya mean the headlights switch on the dash?

Ye the flash is working, the full beam and sidelights are working. Just the 'dipped' beam isnt coming on

Terminal 56b is on the dip/flasher switch on the steering column. Your have to remove the plastic shroud to get to it. j.