Expert: Brad Sears - 1/9/2010

Question
I have a Mustang II 1977, Mach I version, and after six months of change my halogen bulbs (55/60W) for other brighter bulbs (100W) my headlights suddenly turn off, just the low lights. During this event the high lights are working well. I verified the voltage in the dimmer switch and voltage was not present for the low lights line.  I read other questions I for older Mustangs and the problem could be solved changing the circuit breaker. For my Mustang I tried to find this circuit breaker but I could not find it. Now I change the brighter beams for halogen beams (55/60W) and for the original sealed beams and I also had installed a headlight relay and replaced the headlight switch but the problem is still present.  Please, I need your help, what should I do, Do you know where the circuit breaker is installed in this Mustang?
Thanks.

Answer
The circuit breaker is in the headlight switch and is not built to take a 100W load. In this system you will need two headlight relays, one for low beam and one for high installed after the dimmer switch with the feed wire for the relays coming from the battery through an in line 30 amp fuse.
Brad