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Discussion Starter · #1 ·
Have spent the better part of a month troubleshooting this on and off. Turn signals all work on passenger side, on drivers side the rear (tail) turn signal and the side mirror turn signal both work, however the front turn signal does not. So the blinker always starts normal speed and then goes to hyper speed clicking. I've already replaced the bulbs and the parking lights (same bulb, other filament) work fine, as do my low and high beams.

I wasn't getting any power to the the pigtail harness pin for the turn signal (it's separate from the parking light pin) so I replaced the front headlamp pigtail connector. Still not getting voltage to the left front turn signal supply voltage pin so it has to be an issue between the connector and the fuse box right? However, I don't see a fuse in the under hood fuse box for the turn signal. It looks like it shares the same fuse as the parking light, and the parking light works fine and I already have inspected the fuse (it's fine). Does anybody have any ideas where I can check next?

I also know that there is no flasher (its built into the BCM I believe), so I'm running out of things to check.
 

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Discussion Starter · #3 ·
new GM 2007 and new have a load of corrosion on the fuse pins/electrical connectors ....the CCP is made in china troubleshoot the connectors ..
Thanks j cat, I replaced the head lamp harness connector and I'm getting ~12 v to every pin with the exception of the turn signal pin. Nothing in the manual points to an individual fuse for the front turn signal (it appears to share the parking lamp fuse and that light is fine) so it must be a short in the wire between the fuse box and the connector, right?
 

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I'd be surprised if the signal light and the park light shared a fuse, 2 different circuits. The do share bulbs, but they are different filaments.

If there is any fuse sharing, it would be with the brake and the signals; they share the same bulb and the same filament.

But usually they are fused by side, so if the signal/brake works on that side at the rear, the fuse is good.

I would expect a poor ground.

I know you found a connector pin without signal voltage; but I would still be sure the ground is good.
Yes I know the parking light in that corner works; but you could still have a poor ground at that light.
The parking light draws a lot fewer amps than the signal.
The lower current results in a smaller voltage drop and the light can work.
The higher current draw of the signal will result in a bigger voltage drop and the light may not work.

Just add a wire from the ground point to the battery neg and try it.
 

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Discussion Starter · #5 ·
I'd be surprised if the signal light and the park light shared a fuse, 2 different circuits. The do share bulbs, but they are different filaments.

If there is any fuse sharing, it would be with the brake and the signals; they share the same bulb and the same filament.

But usually they are fused by side, so if the signal/brake works on that side at the rear, the fuse is good.

I would expect a poor ground.

I know you found a connector pin without signal voltage; but I would still be sure the ground is good.
Yes I know the parking light in that corner works; but you could still have a poor ground at that light.
The parking light draws a lot fewer amps than the signal.
The lower current results in a smaller voltage drop and the light can work.
The higher current draw of the signal will result in a bigger voltage drop and the light may not work.

Just add a wire from the ground point to the battery neg and try it.
Thanks Roy, so you're saying to add a wire from the ground point on the frame and run it to the negative terminal of the battery? Or to add a wire to the ground points on the back of the connector to the negative battery terminal? There are two ground wires, but according to the grounding diagram that I found they both terminate at the same grounding point on the frame (G100). Thank you for your assistance.
 
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