Brake, Headlight and Turn Signals are dead

[deadhead]

I am making progress on my 1966 1200A PU. She starts, runs and comes to a stop now. All lights are dead however. Does anyone have a suggestion on how to best diagnose the situation? I always like to start with the simple (and cheap) repairs first LOL! A few pictures are here..

 

[FDChappie]

Fuses would meet that criteria.

 

[Scoutboy74]

Nice little truck. With exterior lighting issues, I like to start at the bulbs and work my way back to the power source in a logical and methodical manner. Pop the red and amber lenses off so you can examine each of the bulbs. You'll note that these bulbs are a dual filament design, one being bright for signals/brakes and the other being dim for tails/markers. A bad bulb filament is easy to spot, so look for and discard any of those you might find. Next thing to look at is the contact surfaces on each of the bulbs. Are they shiny or badly corroded? Shine them up if needed. Speaking of corrosion, that leads me to the topic of grounds. Bad grounds are to blame for a vast majority of external lighting issues on any vintage vehicle. These lights derive their ground through lousy contact between the housings and the sheet metal. Any corrosion present there could potentially hamper the ground, so pop the housings free from the sheet metal so you can see how bad it looks and then take corrective measures. With that completed all around, reset the housings and bulbs. Did you regain any function? Let us know and we'll go from there.

 

[deadhead]

Fuses would meet that criteria.

FDChappie, Thank you! I like the way you think.

 

[deadhead]

Nice little truck. With exterior lighting issues, I like to start at the bulbs and work my way back to the power source in a logical and methodical manner. Pop the red and amber lenses off so you can examine each of the bulbs. You'll note that these bulbs are a dual filament design, one being bright for signals/brakes and the other being dim for tails/markers. A bad bulb filament is easy to spot, so look for and discard any of those you might find. Next thing to look at is the contact surfaces on each of the bulbs. Are they shiny or badly corroded? Shine them up if needed. Speaking of corrosion, that leads me to the topic of grounds. Bad grounds are to blame for a vast majority of external lighting issues on any vintage vehicle. These lights derive their ground through lousy contact between the housings and the sheet metal. Any corrosion present there could potentially hamper the ground, so pop the housings free from the sheet metal so you can see how bad it looks and then take corrective measures. With that completed all around, reset the housings and bulbs. Did you regain any function? Let us know and we'll go from there.

Scoutboy, Thank you for your ideas. This sounds reasonable and I will follow up. Unfortunately, like a lot of people right now I have about 3 inches of snow and 28 degrees outside. Give me a little time and I'll give an update. Thanks!

 

[Scoutboy74]

Very good. In the meantime, do you have an incandescent test light at your disposal? It's just a pointed probe with an encased light bulb and an alligator ground clip with a length of wire running between the bulb and clip. If not, you'd do well to get yourself one. They're inexpensive, yet invaluable tools for basic automotive troubleshooting. Hand held meters are great to have as well. In this case, when all you're trying to determine is the presence or lack of voltage at any given place, rather than a precise amount of voltage, a simple light to indicate "deal" or "no deal" really fits the bill. This is foreshadowing of the next step if your inspection and clensing measures don't bear any fruit. With verified good bulbs and grounds, but still no lights, you'll next need to check for the presence or lack of voltage at the bulb sockets. Like Chappie said, checking fuses is quick, easy and essential as well. The headlights themselves aren't fused though. For obvious safety reasons, the headlight switch incorporates a resetting circuit breaker for the headlight circuit. Aging circuit breakers and light switches can certainly fail. At this stage, every single component that makes the lights work from stem to stern is a potential culprit until physically ruled out.