521.. the left turn signal?

[crafty1]

I started having weird issues now, the left turn signal seems to "stop" working.  I went outside to look, its seems to be working, but on the dash, no clicking sounds.  --  There was a point when both left and right stopped working on the inside as well.  Any suggestions?

 

thanks

 

[MicroMachinery]

When's the last time you replaced your flasher? Also, cleaning the fuse box and connections is never a bad idea.

[Stoffregen Motorsports]

Check for bad grounds. I know everyone says that, but that's because it's true.

 

There is usually a ground point at each corner of the vehicle and they're pretty easy to spot.

[datzenmike]

If the ground was bad none of the lamps that share it would light.

 

 

 

Looks like you have an intermittent problem. Hard to chase down.

 

The old flashers were load dependent... in other words they needed at least two good lamps in order to flash them. If a bulb blew out the flasher didn't work on that side. Like-wise if you had a trailer with extra bulbs it would flash annoyingly faster. Today they are electronic and flash at the same speed no matter how many bulbs are used.

 

The clicking sound is only the relay inside opening and closing. Some are louder than others. No clicking means no working.

 

If the right side flashes then the flasher unit is working. Replacing it won't change anything.

 

I would take a good look at the front and real signal lamps. Are they corroded and rusty?  Making good contact with the plug bases when pushed in?

[thisismatt]

The turn signal stalk switch is also a POS, but it doesn't seem like that would be your problem.

[DanielC]

First, turn on the four way flashers.  They override the turn signal wiring, and if they work, it narrows the problem down into the wiring on the turn signal switch, and wiring in the cab.  the power for the turn signals goes through the four way switch.  Make sure the four way switch is completely off, and not half way off.

 

Make sure all the lamps (bulbs) are good.  You can do that when the four way flashers are on.  On the rear of the truck, make sure the taillights, stop lights, or back up light are not trying to flash, with the four way lights on.  If they do, that is a definite indicator of a bad ground.

 

The front turn signals ground to the cab sheet metal.  There should be a black wire under one of the voltage regulator screws, that go the the alternator frame, and the negative battery post.

The rear turn signals have a harness that connects all the lamps.  this harness has a ground lead that goes to the taillight frame.  The taillight frame should ground to the bed of the truck, and the bed should ground to the frame of the truck.  You can eliminate some ground problems by running a wire directly from the taillight frame to the truck's frame.  Do this on both rear taillights.

[dat521gatherer]

If  they are working on the outside but not on the dash check the dash bulbs.

[datzenmike]

Try the 4 way flashers to check the dash bulbs. Either they, work or not. If not working check that the rears and fronts are.