Turn signal issues

[57taskforce]

I've been scouring over the search function, but haven't been able to find what I'm looking for. Here's my symptoms, my K20 didn't have any signals but hazards, brake lights, everything else works. After poking around with my test light and multimeter, Turn signal switch is shot and flasher is bad. No biggie I will replace them. However, I decide to do some testing on the body side of the steering column half moon plug. After replacing the flasher, I've got power at all three of the wires that should have power. I made a jumper wire and started to jump power from the purple hot to the various wires in the plug to test the individual light circuits as outlined in post 5 of this thread: http://67-72chevytrucks.com/vboard/s...d.php?t=645408
All circuits check out except for the light blue/drivers front fender marker light. (My truck doesn't have a front bumper currently installed so no bumper parks/signals.) when power is applied the light stays lit and doesn't flash. If park lights or headlights are on the driver front fender marker light goes out. Also there is no left signal indicator lit on the gauge cluster. Passenger side works as it should so I don't think it's an issue with no front bumper lights. Again all other lights work as they should in there various functions. Any ideas?
I'm wondering if I've got a bad bulb in the left signal indicator on the dash, I'm not sure if this would cause the issue I'm having. I was gonna swap a new bulb in after work but I didn't get home in time before it got dark.

[VetteVet]

I would check the ground on the left marker light. If it has a poor ground the voltage drawn by the headlights and tail lights might not be enough to overcome the high resistance caused by a bad ground on the marker light.
You may have a bad bulb in the cluster or it might not be making good contact with the ground on the cluster. the power wire for the cluster turn indicators is wired in parallel with the front signal lights. If you jump between the purple or brown wires in the column connector and the light blue wire the cluster light should come on. Purple needs key on.
Try it on the dark blue wire (right side indicator) to verify.
Do the markers flash with the front turns?

[71CHEVYSHORTBED402]

I'm green, and colored blind to boot. Sounds like a ground issue to me. I think I'd look at the wires at the core support. For instance, the black wire from the marker light soldered onto the blue wire for the park light.

[VetteVet]

Here's the wiring diagram to help you out.





You will notice that the marker lights are fed by two, brown wires and they ground to the fenders. this is where the bad ground to the fender comes into play.

[57taskforce]

I was hoping you'd find this thread vettevet! The dark blue wire does flash the right signal indicator on the dash and the right front marker in the fender. Thanks for the diagram it does clear things up some. I will check the fender ground tomorrow.

[57taskforce]

After some poking around this evening I believe the indicator bulb is the culprit. I pulled my cluster and sure enough the passenger signal indicator bulb is blown. With the cluster unplugged I can replicate the exact symptoms on the dark blue wire as I was getting on the light blue wire. I'm gonna get some bulbs and give it a try.

[VetteVet]

Originally Posted by 57taskforce

After some poking around this evening I believe the indicator bulb is the culprit. I pulled my cluster and sure enough the passenger signal indicator bulb is blown. With the cluster unplugged I can replicate the exact symptoms on the dark blue wire as I was getting on the light blue wire. I'm gonna get some bulbs and give it a try.

not that it matters but I think you said the left indicator was bad.
I think you have a handle on it. VV