Another blinker problem...

[Clifford69]

I have read through a ton of threads and I haven't happened upon one that describes my problem...

69 Chevy C10 with an American Autowire kit. I took the front end off to replace the transmission when I put it all back together I discovered this problem.

All of my blinkers work normally with the lights off except for the front passenger side blinker. When the lights are on the front blinker light doesn't come on at all, everything else works as normal.

On the 1157 bulb there is a long filament and a short filament. The way it should work is the short filament is the blinker and the long filament is for the parking lights - at least that's how it works on the drivers side. On the passenger side the long filament lights up with the blinker when the lights are off, but nothing works when the lights are on.

I have switched the leads with no change to the problem. I also ran a ground wire from the battery to the light socket with no change. Positive voltage are nearly identical between the drivers side and passenger side blinkers.

Any assistance would be greatly appreciated!

[dmjlambert]

I used to have a thread bookmarked that talked about connecting jumper wires at the turn signal switch half moon connector under the dash, but I have not been able to find it again. Here is the routine from notes I took:

Disconnect the turn signal switch at the half moon connector under the dash. It takes finesse to disconnect it, there are tabs that you can try not to break off. Once disconnected, on the truck wiring side of the connector, connect an alligator clip jumper wire to the terminal fed by the purple wire. That is the wire that comes from the flasher. Connect the other side of the jumper wire to the terminal fed by these colors, one at a time, to make these various lights flash. This tests your truck wiring to the lights:
light blue - left front turn signal
dark blue - right front turn signal
yellow - left rear turn signal/brake light
green - right rear turn signal/brake light

If the lights come on and flash when you give each a trial like this, but some don't work when the turn signal switch is connected and you move the lever, then that would indicate the turn signal switch is broken.

Here are all the notes about that connector:
purple - from flasher
light blue - left front turn signal
dark blue - right front turn signal
yellow - left rear turn signal/brake light
green - right rear turn signal/brake light
brown - from hazard flasher
white - from brake pedal
black - horn button

[Andy4639]

There should be a rubber connector in the radiator support above the light housing. When you pull it a part there should be 3 wires connectors inside it. Take it loose and put a test light in each fitting and do your lights to see if it's getting juice to the light fixture. If it does then it's more than likely a grounding issue at the housing. The ground is through the light housing.

[Clifford69]

Originally Posted by Andy4639

There should be a rubber connector in the radiator support above the light housing. When you pull it a part there should be 3 wires connectors inside it. Take it loose and put a test light in each fitting and do your lights to see if it's getting juice to the light fixture. If it does then it's more than likely a grounding issue at the housing. The ground is through the light housing.

I have checked the ground in the light fixture several times and I get good voltage from both turn signals (around 9-10 volts). I have also run a ground wire from the negative battery post to the housing just to confirm, and there hasn't been any change in the symptoms.

Keep throwing ideas at me, I am willing to try nearly anything!

[Clifford69]

Another electrical issue due to a bad ground. My problem was the light housing wasn't properly grounded to the grill. When I attached the battery ground directly to the signal housing screw everything worked properly. Thanks for the help!!

[Clifford69]

Originally Posted by dmjlambert

I used to have a thread bookmarked that talked about connecting jumper wires at the turn signal switch half moon connector under the dash, but I have not been able to find it again. Here is the routine from notes I took:

Disconnect the turn signal switch at the half moon connector under the dash. It takes finesse to disconnect it, there are tabs that you can try not to break off. Once disconnected, on the truck wiring side of the connector, connect an alligator clip jumper wire to the terminal fed by the purple wire. That is the wire that comes from the flasher. Connect the other side of the jumper wire to the terminal fed by these colors, one at a time, to make these various lights flash. This tests your truck wiring to the lights:
light blue - left front turn signal
dark blue - right front turn signal
yellow - left rear turn signal/brake light
green - right rear turn signal/brake light

If the lights come on and flash when you give each a trial like this, but some don't work when the turn signal switch is connected and you move the lever, then that would indicate the turn signal switch is broken.

Here are all the notes about that connector:
purple - from flasher
light blue - left front turn signal
dark blue - right front turn signal
yellow - left rear turn signal/brake light
green - right rear turn signal/brake light
brown - from hazard flasher
white - from brake pedal
black - horn button

Thanks. I tried this with the same result, so that should eliminate the turn signal switch??

It's overcast today so I noticed that when the right blinker is on both of the long filaments on both turn signals blink, not just the one on the right. Also, when I turn the lights on the turn signal indicator in the dash lights up. It seems like a ground issue but everywhere I check I seem to have a good ground. I'm still lost...