I own a 73 plus 2 and have recently encountered total lighting failure whilst driving at night. This seems to occur when driving hard and is accompanied by a soft pop or ping. After ten minutes or so, normal service is returned and I can creep home.
It has been suggested to me that late cars had the headlight circuit wired directly to the dash switch instead of using relays to operate the headlights. To stop everything from bursting into flames a bi-metalic strip based cut out was added which cuts the power when things get a bit hot.
Frankly this seems a crazy system as it plunges you into complete darkness with no warning. I’m considering converting the car back to the original relay system but it occurred that I may just be misunderstanding the bi-metalic strip system. Does anyone know whether renewing the bi-metalic strip unit would solve the sudden darkness problem, or simply postpone it until the moment when the dash board starts smoking (just to add to the fun)? Are there any benefits to this system?
Regards
Simon