so ive been trying to work out all these lighting problems with 67 caprice wagon and so far ive figured out that i probably need to head light swtich(only half of my gauge lights turn on and my license plate light isnt getting power).
now someone pointed out when im driving at night with my lights on and i turn my right turn signal on my left brake lights turn off and then when i turn the signal off all 3 lights come back on.then when i turn my left signal on nothing happens at all,but when i have my lights off all my signals work just fine.HELP a new guy out thanks
The problem with these old cars is that the steel body is designed to be the return "wire" to complete the circle. You may have a great ground from the bulb to the light housing but not have any kind of ground path were it bolts to the car due to corrosion. Where the sheet metal panels are spot welded together could be corroding causing the resistance to go up. Somewhere between the front of the car where the battery is and the back where your light is the connection breaks down. I recommend doing what the factory did with the plastic bodied Corvette, and that is to run a separate ground wire that can return the current to the battery as that will remove the rusty steel body as the return circuit.
There are three bonding straps in the engine compartment. Two go from the firewall to the engine valve cover bolts. One goes from the car body down to the frame. It's under the heater box on the firewall.
Since the negative cable from the battery bolts to the engine block, a good ground is needed to the body of the car, hence the two grounding straps from the engine to the firewall. Funny things can happen without them.