Electrical ? Turn signal lamps and map llight

1968 GTX
I am having trouble finding the problem with the instrument panel turn signal lights. Neither lights up when in use. The map light does not work either. Outside lights, blinkers work fine. Flashers work fine. Dimmer switch works fine. Dome light works.
Also, there is a small cylinder (with three prongs) under the dash that plugs into a connector with two yellow and one pink wire. What is it. No identification on it.
Thanks

www.mymopar.com will have wiring diagrams. the can is either the turn signal or the hazards "flasher". You might seperate the lower end of the harness that connects up to the dash & jump 12V to the appropriate terminal & see if the lights light up & either work upstream or downstream from there, kinda generic but that'd be a start.

That small can is probably the timer for the light package. Turns ign switch lamp on for timed period once door is opened, and usually gets warm when door is open for a while. Provided it's all working. The map light should be tied in with pink wires maybe?

Could just be bad bulbs for the turn indicaters.

Yes it does get warm. Thanks

new bulbs

bulbs new

the round black bakelite plugin on the pins on theback of the printed circuit board on the dash up there, can you trace out the other end of that harness loom & jump fire to the 2 wires for the respective indicator lights?

Ive had lots of the black connectors not carry current.I have a supply that Ive pulled and some new ones I bought.NAPA did carry them.Rocky

You have two separate problems, as the dash blinker light circuit is separate from the map light.

The blinker lights run off the round multi-pin connector on the dash light circuitboard. the copper traces on that board weren't treated from the factory and tarnish at the lightbulb connector. also, the pins that the round multi-pin connector are attached to are riveted in place, and they are prone to get loose with vibration and can even break or tarnish around the area the pin makes contact with the circuit board. I don't believe your blinker switch or the steering column connector is the problem because your blinkers work. I tend to think it is at that connector on the back of the gauge cluster.

The canister is as mentioned by another member, your key light timer can. it works on heat.

The map light is part of the curtesy light circuit that can include the console and dome lights. with that circuit, all the lamps have a live positive feed connected all the time. when you open the door, use the dimmer switch or flip the map light switch, what you are doing is grounding the circuit to the body. they are all tied together. This is why when you open the door the map light comes on. The map light has a switch that has its own ground so that you can turn it on while the other lights stay off. Pink energizes the switch and yellow is ground. if you remove the fixture with the two screws that hold it to the dash it is very easy to test for continuity with a circuit tester light or volt/ohm meter while it is still attached.

Good info

Like Bug Bad Bee said, you have two different issues.

Map light - Yellow (switched ground) and Pink (Full time +12V) are the correct colors for the courtesy lights but I am not familiar with any 3 prong round connector. The only ones I have dealt with have a two prong and single bullet connector. Do you have a console?

Maybe these links will help. The third link is harder to follow but usually more accurate.
http://www.mymopar.com/downloads/1968/68BelvedereGTXSatelliteRoadRunnerA.JPG
http://www.mymopar.com/downloads/1968/68BelvedereGTXSatelliteRoadRunnerB.JPG
http://www.mymopar.com/downloads/1968/68BelvedereGTXSatelliteRoadRunneFull.pdf

Turn signal lights are on a completely different circuit & fuse.

Thanks