I discovered that my tail lights only work when the headlight switch is set to parking lights. First thing I did was to replace the relay but the relay is not the problem. In the fuse/control panel at the co-pilots feet, connector #10 connects the switches with the relay in the back. The only time #10 has power is when the headlight switch is in park mode. I must have a bad switch, but which one. Does the headlight switch or the running lights switch control the tail lights? With that answered, I can replace either of the switches, or perhaps find another power source for the tail light relay.
The headlight switch controls the tail lights. With the running lights on, the tail light will still be off IF the headlights are not in the parking light or the headlight position.
Thanks Michael, and that tells me that the headlight switch is bad. A temporary solution may be to run a jumper between the front, or back, terminal board connections for the tail lights and the running lights. This should cause the running lights switch to actuate the tail lights relay thereby turning on both the running lights and the tail lights. The running lights are protected by a 15 amp fuse and it seems to me that the tail light relay should not add many amps. What do you think?
That would likely work as a stop gap measure. Without a diode, that would turn on the running/clearance lights anytime the headlights were on also thus defeating the purpose of the separate clearance light switch if you ever want to flash your clearance lights. If you are just driving the relay trigger, you will be pulling very little additional current through the clearance light circuit. If you are on the load side of the tail light relay, I would be more concerned about the load.
Chester,
Look at the switch. I am guessing that it is a double pole double throw switch. The side with the running lights will be jumpered front terminal to rear terminal. If it is a double pole double throw switch, simply pull off the terminals and rotate the switch 180 degrees.
Or jumper the headlights to the rear pole. That will eliminate your running lights only mode until you get a new switch.