New to the list. Just purchased a 1975 F150 from Iowa, originally from Fairmont MN with 71 k ? on it. Has some minor rust starting but nothing to serious for a 30 year old truck. The voltage regulator was bad and before I could replace it I ended up loosing both high and low beam headlights. Have not been able to locate the fuse, tried both the fuse box and looked for an in line fuse, no luck.
Any suggestions? Thanks in advance.
Jim

 

Sounds like a nice truck.

Do all the other electronics work - wipers, park lights, radio, heater fan?

Usually when the headlights go out (but park lights still work) the problem is either the headlight switch or the dimmer switch on the floor - more often its the dimmer switch...

Dimmer switch will run about $15 and headlight switch will run about $30.

Marty

 

Marty , Thanks for the reply. Have already replaced the dimmer. So I think the switch will be the next item.
Jim

 

Do the park lights come on? dash lights?

Marty

 

Yes, still have parking lights, dash lights wipers and heater fan.
Jim

 

Take a test light and test for power at the back of the headlight. More than once, I've seen both headlight bulbs bad...

Did both lights go out together? Did the high beam and low beam quit at the same time?

Marty

 

Mart,
First I lost high beams and the next day I lost the low beams. I did not know it at the time but my voltage regulator was fried and had to be replaced. Almost cooked the battery.
Jim

 

Try testing for power at the headlight. It's possible the high voltage fried the bulbs...

Marty

 

You can get close to 16 volts out of the alternater if the reg packs it. I would check the lamps with an ohm meter and the connecters to head lts with a voltmeter.