Technical Headlight Failure

[BobAllan123]

Hi, I have a strange problem!
When driving on a journey in the dark, usually after about an hour, the headlights fail, both dip and main beam. Also the hazard flashers and the inside dome light also fail. It happened twice and each time I fiddled with the fuses and relays and after about 15 mins fiddling the lights came back on again. I could not find the problem because it is intermittent so i rigged up an emergency switch which is a power supply direct to the lights from a switch in the cab. Last weekend I was on a long journey again, after an hour the lights went out and my emergency switch worked. Need to get to the root of the problem though so does anyone have any ideas? There is a new earth now from both bulbs so unlikely to be an earth problem (as I have read in other posts). It is like something is overheating then when it cools down it works again. I swapped the headlight relay as well but as it only operates the headlights I didnt think it would make any difference and it hasn't.
Its not a motor home, just an old panel van I bought to take stuff to our holiday home which is two hours away!
Thanks.
Bob

 

[Stratos41]

Bob
Since problem comes to many circuits and the car is quite old I believe you have loosed wires or dirty terminals. If there is not any noise during the interruption (loosed cables) then probably is rusted terminals. Unplug the battery terminals.
Find in the main fuse box the terminals of the main lights. Remove them, clean and restore. Get out the light relays sprey with contacts cleaner and back again.
SMELL the fuse box closely. If smells burned you have to visit an electrician.
Good Luck