headlights not working

[m4ckg]

I haven't had the car tested for 4 years and one of the things it's failed on are the headlights not working. Bulbs are fine as are the fuses, side lights and rear lights work so was wondering if it could be an earthing problem or some sort of relay. Any thoughts?

[Oldred_V8S]

I think a multimeter is your friend here.

You should undertake some voltage drop tests. Put the meter probes in the rear of the lamp holder (if poss) on DC volts setting (20v)
Switch the lights on and see if you get 12v on the multimeter.
If not, put the black lead to a good earth point. 12v = Y/N, if Y then you have a bad earth to the lamp holder, if N you have a 12v supply issue.

[m4ckg]

Thanks for that Oldred, do you know where the earth point would be for the lights ?

[J400GED]

I think it's on front of the right hand chassis rail below the rad outlet hose.

[Oldred_V8S]

m4ckg said:

Thanks for that Oldred, do you know where the earth point would be for the lights ?

I dont, sorry.

[m4ckg]

J400GED said:

I think it's on front of the right hand chassis rail below the rad outlet hose.

Thanks :-)

[taylormj4]

Think there is also a box with a PCB in that serves the headlamps and other things. It's located within the dashboard and needs it lifting to access. I had a problem many years ago with headlamps and it was the switch that had shorted to the metal back of the dash panel and blown tracks off the PCB in this box.