Turn signal problem. Fronts wont work but rears do??
10-09-2008, 01:33 PM
#1
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Turn signal problem. Fronts wont work but rears do?? Ok on my 02 T/A my front turn signals will not flash when I turn on my left or right blinker. Both rears will flash as they are supposed to, even the little green arrow in the car will actually flash, but the fronts will not do anything. I have changed the bulbs, sockets, turn signal flasher and hazard flasher. Oh and the fronts will be lit up for DRL operation but just will not flash.
10-09-2008, 04:10 PM
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No they are not always on, they will light when I unlock the car with the remote like they normally would, they light up when I have my headlights on like they normally would, but when I go to turn the turn signal on they will not work.
10-09-2008, 04:31 PM
#4
So the DRLs don't work? The front bulbs are dual filament - a dim filament for parking lights and a bright filament for turn signals and daytime running lights. The dim parking light filament is the one that flashes for the alarm and goes on when the headlights are on.
Use a test light to check for power on the blue wire at the front socket (light blue wire on left side, dark blue wire on right side) when the ignition is on and the parking brake is off (DRL function).
If there's no power at the socket then test the DRL module behind the radio. You should have power output on the same color wires. If so, there's a break in the wires someplace between the DRL module and the front sockets. If not then the DRL module itself is the problem. The DRL module also controls the front turn signals so it could be responsible for all the symptoms you describe.
Use a test light to check for power on the blue wire at the front socket (light blue wire on left side, dark blue wire on right side) when the ignition is on and the parking brake is off (DRL function).
If there's no power at the socket then test the DRL module behind the radio. You should have power output on the same color wires. If so, there's a break in the wires someplace between the DRL module and the front sockets. If not then the DRL module itself is the problem. The DRL module also controls the front turn signals so it could be responsible for all the symptoms you describe.
10-10-2008, 07:10 AM
#6
There are two connectors at the DRL module - an 8-pin black connector and an 8-pin blue connector. In the black connector you will find the same light blue and dark blue wires as at the front sockets (left and right respectively). You will also find a light blue with white wire and a dark blue with white wire that are the input from the turn signal switch. Unplug the black connector and use a test light or multimeter to test for flashing power on those two wires when the appropriate turn signal is on. If that checks out then you know that turn signal power is getting to the DRL module but it's not getting from there to the front lights so the module must be defective.
