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Replaced both front bulbs as well as passenger socket.
When hazards are turned on, rears both work/flash with no working front/side hazards.
Also, when turn signal is attempted, turn signal arrow flashes on dash but front signal light does NOT turn on (rear flashes normally).
Weird thing about this is that both front DRL (daytime running lights) work when interior switch is turned to middle switch and "on" BUT do not turn on when vehicle is started.
Doesn't sound like flashers or bulbs are the problem here. Bad ground to front lights for flashers to work? Maybe signal wire isn't getting power?
First, there are two filaments in the front bulbs - a dim filament for the parking/running lights and a bright filament for the DRLs and turn signals. The two operate on separate circuits so the fact that you get light from the bulbs with the parking lights or headlights on doesn't really tell us anything about the turn signals and DRLs.
Something else about your description is troubling... with a factory configuration, when the front lights don't work, the other turn signals (rear and dash) will come on solid and not flash at all. Have you made changes such as an electronic flasher and/or LED bulbs? Have you been doing anything behind the stereo that might have affected the DRL module mounted to the defroster duct behind the head unit?
Barring the obvious things (like the DRL module unplugged), you should start with a test light or multimeter to determine if you are getting power on the blue wire at each front socket when the ignition is on and the parking brake is disengaged (DRL function) and flashing power when either the hazards or turn signals are on. I suspect you'll find that you aren't getting the proper power at the sockets so you'll have to work backwards from there to determine why.
It is very doubtful that you have a ground problem since your parking lights work.
Maybe I misspoke in my first post. Rear flashers and turn signals work perfectly (dash turn signal now works correctly after turn signal flasher was replaced). Front turn signals and front flashers DO NOT turn on at any point at all. Ever.
Also, the only time I see the actual front parking light come on is when I manuall flip the interior light dial (left of steering wheel) from its far left spot, to either the middle click, or the far right click (causes headlights to flip up).
Is it possible I got bulbs with only a single filament? 3157NA is what I'm using, should I be using 3457A? Seems like they are interchangeable.
I will try to trace down the blue signal wire power source and see if it is an incomplete circuit. If the light turns on but this blue wire isn't feeding the light signal, that would explain the lack of hazard and turn signal lighting, yes?
The side marker lights also follow the same limitations as the front parking/DRL currently. Is it possible I need to replace the Left and right turn relays? Seems like those provide the power to the blue signal wire on each light's socket. Where are these relays located?
EDIT: the relays are likely not the issue, as the hazards also fail to signal the front lights. Has to be the blue the blue1414 and blue 1415 signal wires to each of the front lights activating the second filament of the bulb.
What could cause BOTH of these wires to fail to provide signal?
Maybe I misspoke in my first post. Rear flashers and turn signals work perfectly (dash turn signal now works correctly after turn signal flasher was replaced). Front turn signals and front flashers DO NOT turn on at any point at all. Ever.
Yes, I got that except that you hadn't mentioned replacing the flasher with an electronic one (electronic flashers are not dependent on the current load produced by the front bulbs in the same way the stock thermo-mechanical flashers are).
Originally Posted by Squirts11
Also, the only time I see the actual front parking light come on is when I manuall flip the interior light dial (left of steering wheel) from its far left spot, to either the middle click, or the far right click (causes headlights to flip up).
That is exactly as expected since the dim (parking/running) filament is only activated by the headlight switch in the Park or On position.
Originally Posted by Squirts11
Is it possible I got bulbs with only a single filament? 3157NA is what I'm using, should I be using 3457A? Seems like they are interchangeable.
Not if you got 3157, 3357 or 3457... those are all dual filament bulbs. The equivalent single filament bulbs would be the 3156, 3356 and 3456.
The differences in the second digit relate only to the candlepower (brightness) of the filaments. The NA at the end simply means Natural Amber (amber colored glass) and A means Amber (coated glass).
Originally Posted by Squirts11
I will try to trace down the blue signal wire power source and see if it is an incomplete circuit. If the light turns on but this blue wire isn't feeding the light signal, that would explain the lack of hazard and turn signal lighting, yes?
The front sockets have three wires... black for ground, brown for parking/running light power and blue for DRL/turn signal power. The black wire goes to a grounding bolt on the top of each side of the radiator support. That is not your problem. The brown wire is connected (with all of the other running and marker lights) to the headlight switch. That also is not the problem.
The blue wires go to the front sockets from the DRL module behind the stereo head unit. That module switches power source between steady power for DRLs and flashing power for turn signals through the use of two internal (non-serviceable) relays. The problem you describe would have to be the sockets, the wires from the DRL module to the sockets (unlikely that both side wires would break at the same time), or the DRL module itself (also unlikely unless you've been working on something near there). It can't be the power input to the DRL module because there are two separate power feeds to the module for DRL and turn signals.
I suspect you'll find the problem is the connections of the sockets to the factory wiring harness or corrosion in the sockets themselves (a common problem).
Yes, I got that except that you hadn't mentioned replacing the flasher with an electronic one (electronic flashers are not dependent on the current load produced by the front bulbs in the same way the stock thermo-mechanical flashers are).
That is exactly as expected since the dim (parking/running) filament is only activated by the headlight switch in the Park or On position.
Not if you got 3157, 3357 or 3457... those are all dual filament bulbs. The equivalent single filament bulbs would be the 3156, 3356 and 3456.
The differences in the second digit relate only to the candlepower (brightness) of the filaments. The NA at the end simply means Natural Amber (amber colored glass) and A means Amber (coated glass).
The front sockets have three wires... black for ground, brown for parking/running light power and blue for DRL/turn signal power. The black wire goes to a grounding bolt on the top of each side of the radiator support. That is not your problem. The brown wire is connected (with all of the other running and marker lights) to the headlight switch. That also is not the problem.
The blue wires go to the front sockets from the DRL module behind the stereo head unit. That module switches power source between steady power for DRLs and flashing power for turn signals through the use of two internal (non-serviceable) relays. The problem you describe would have to be the sockets, the wires from the DRL module to the sockets (unlikely that both side wires would break at the same time), or the DRL module itself (also unlikely unless you've been working on something near there). It can't be the power input to the DRL module because there are two separate power feeds to the module for DRL and turn signals.
I suspect you'll find the problem is the connections of the sockets to the factory wiring harness or corrosion in the sockets themselves (a common problem).
Thank you for the reply. I actually did replace the passenger side socket unit and spliced in the new 3 wires to the factory wiring. This didn't seem to help so I skipped replacing the drivers side.
I have done nitrous wiring behind the center console but have never removed the factory radio or the entire dash.
Replaced the DRL module and noticed no change at all. Still no front turn signals or front hazards. DRL lights are also not lit unless headlight switch it turned to middle position, then both front lights turn on.
The car is only activating one of the two dual filaments in the bulb.
Will be using a second DRL module to confirm this in a week, then will go from there. Any other suggestions?
Oddly enough, I don't recall suggesting replacing the DRL module. If that had worked, it would have been the first one to fail that I've heard about in the 17 years since they started using that module in 4th generation f-bodies... in other words, a real long shot.
Your best bet is to use a test lamp or multimeter to test for power on the socket contacts for the blue wire at the front lamps. Assuming that you won't have power there (because if you do then it's simply a burned out bulb), next check for power on the light blue (left) and dark blue (right) wires at the DRL module (with the conector still plugged in to the module). If you have power there then you know there is a break in the wiring someplace between the module and the socket. This is by far the most likely case. If not, check for turn signal power on the light blue/white (left) and dark blue/white (right) wires at the DRL module. Those are the input from the turn signal switch to the module. But even if they aren't working that still wouldn't explain the lack of DRL power so it is unlikely to be your problem.
So, once you've confirmed that the problem is in the wiring between the DRL module and the socket, cut off the replacement socket you installed and check for power on the blue wire of the original factory harness. It is likely the power will be there indicating that the problem is between there and the bulb - in other words the socket itself or the way it was connected. From there it should be a simple matter to narrow it down and repair the problem.
Oddly enough, I don't recall suggesting replacing the DRL module. If that had worked, it would have been the first one to fail that I've heard about in the 17 years since they started using that module in 4th generation f-bodies... in other words, a real long shot.
Your best bet is to use a test lamp or multimeter to test for power on the socket contacts for the blue wire at the front lamps. Assuming that you won't have power there (because if you do then it's simply a burned out bulb), next check for power on the light blue (left) and dark blue (right) wires at the DRL module (with the conector still plugged in to the module). If you have power there then you know there is a break in the wiring someplace between the module and the socket. This is by far the most likely case. If not, check for turn signal power on the light blue/white (left) and dark blue/white (right) wires at the DRL module. Those are the input from the turn signal switch to the module. But even if they aren't working that still wouldn't explain the lack of DRL power so it is unlikely to be your problem.
So, once you've confirmed that the problem is in the wiring between the DRL module and the socket, cut off the replacement socket you installed and check for power on the blue wire of the original factory harness. It is likely the power will be there indicating that the problem is between there and the bulb - in other words the socket itself or the way it was connected. From there it should be a simple matter to narrow it down and repair the problem.
This was extremely helpful and sound reasoning, I will follow these steps and have no doubt it will lead to solving the problem.
I'll update when I've solved it. Much appreciated whitebird!
Did you get this fixed?
My driver side front is not flashing.
I replaced bulbs, flasher module under the dash and the socket......
How much is a DRL box?
Did you get this fixed?
My driver side front is not flashing.
I replaced bulbs, flasher module under the dash and the socket......
How much is a DRL box?
Follow white birds steps before you buy a DRL module. I bought a DRL when I was having problems and it ended up being a loose connector under the dash. If it does end up being the DRL I'll let you have the one I bought just pay shipping. It works I just didn't need it.
Ok i checked the wires for power on the drl box:
-With left turn signal activated my voltmeter flashes when testing the light blue/white striped wire while the power at dark blue is continuous.
-With right turn signal activated my voltmeter flashes when testing the dark blue wire while the power at light blue/striped wire is NOT on at all.
Those results are exactly as expected. You have to check the wires that correspond to the same side. The two light blue wires (one with stripe and one without) are the left side and the two dark blue wires are the right side. The striped wires are the input from the turn signal and the solid color wires are the output to the lamps.
So yes, with the left signal on, the light blue with white will have flashing power for the left signal input and the dark blue will have steady power because it's the right side DRL output. What you need to check is if the plain light blue wire also has flashing power output to the left front lamp.
Likewise, with the right turn signal on, the dark blue wire is outputting flashing power to the right front lamp and the light blue with white is doing nothing since it is the left turn signal input. In this case there is no need to check the bark blue with white wire (right signal input) since you could not have the output to the right side without the input also working.
At the DRL box: Both the dark blue wires flash when right turn signal is activated. When left turn signal is activated only the light blue striped wire is showing power. So is this a bad DRL?
If the light blue with white wire shows flashing power but the plain light blue wire doesn't (and assuming the connector is solidly plugged into the module) then yes, the DRL module is not working properly.
05-20-2016, 02:50 PM
No Front turn signals or hazards! Help! 
