04 Silverado Signal/Flasher Issue

[jwhjr]

About a month ago I started getting an intermittent issue when putting on my left blinker. The hazards would go on instead of just the left blinker. It's becoming more frequent now, so now I want to figure out what's going on because it's getting annoying. I've checked to see if any bulbs/fuses are out and they're all good. It doesn't seem to matter if it's cold/warm etc. either. I'm thinking maybe something in the multifunction turn switch is going bad, but that's an expensive shot in the dark (the replacement is around $100) if it's something as simple as a bad ground somewhere. Just wondering if anyone knows of any common issues with those symptoms. I've had to replace the switch in 2 previous GM trucks (99 Suburban and 2000 Blazer). If I do need to replace it, does the wheel have to be pulled off to do it? I did the replacement on the 99, and we had to pull the wheel to replace it.

[Scott K]

I think you are correct, it sounds like a turn signal switch. Yes you would need to pull the steering wheel, and remove the trim covers.

[Gus]

I had the same problem with an 03 silverado. It was the flasher unit and not a switch. I don't think it was in the column, but I didn't fix it myself.

[Jeremy airjer W]

what happens when you turn the four way flashers on and off a bunch off times when this happens?

Or wiggling (up, down, back, forth slightly) the turn signal lever while its in its turn position

If either affects the symptom than the I'll second the switch.

[jwhjr]

Wiggling it while all four are on doesn't seem to affect it. I've tried turning the four way on and off a couple of times in the past and it hasn't seemed to help, but I'll try that again and a few more times the next time it happens. What does seem to work to stop it most of the time is to turn the right blinker on and then go back to the left. I only have 1 left turn on the way into work and it didn't happen this morning, but if it happens on the way home I'll try what you've suggested again.

[muddpuppy]

I also had the same issue in an 03 Silverado, I replaced the Flasher fuse/relay under the dash. It was atillte over $100.00 I could only find it at the dealers. If you pull the drivers side lower dash piece under the steering wheel off you will see the fuse it's li 4" long and 1" thick. was like a 20 min fix

[Jeremy airjer W]

The thing that bothers me about the flasher being the problem is the flasher usually has two different circuits. One for the turn signal and one for the four ways. They are usually fused separately as well. The flasher doesn't care which circuit feeds what all it wants to know is if there is current flowing through the circuit.

The switch is what decides where the power goes. It either goes to the left, right, or all of the above. The flasher only supplies the power or the lack of power. It can not decide where to send the power.

[muddpuppy]

This is for a TrialBlazer but I am guessing they user the same part but if not the issue is the same.

Auto Recall Date: MAY 05, 2005

Vehicle Component: EXTERIOR LIGHTING:TURN SIGNAL

Estimated Vehicles Affected: 286478

Model Affected

2004 CHEVROLET TRAILBLAZER

2004 Chevrolet Trailblazer Defect Summary:

ON CERTAIN TRUCKS AND SPORT UTILITY VEHICLES, THE DRIVER WISHING TO SIGNAL A TURN BY MOVING THE DIRECTIONAL SIGNAL LEVER, (UP OR DOWN) MAY CAUSE THE FRONT MARKER/TURN LIGHTS AND REAR TURN LIGHTS TO FLASH IN A MANNER SIMILAR TO HAZARD WARNING, RATHER THAN FLASHING ON THE DESIRED SIDE ONLY.

Defect Consequence:

THE DRIVER MAY NOT BE ABLE TO CLEARLY SIGNAL THEIR INTENTIONS TO TURN, CHANGE TRAVEL LANES, OR POTENTIALLY WARN OTHERS OF AN IMPAIRED VEHICLE OPERATING CONDITION INCREASING THE RISK OF A CRASH.

Remedy:

DEALERS WILL REPLACE THE SUSPECT FLASHER MODULES WITH A NEW FLASHER MODULE DESIGNED WITH SEALED RELAYS AND MORE DURABLE CONTACT MATERIAL INSIDE OF THE RELAYS FREE OF CHARGE. THE RECALL BEGAN ON AUGUST 4, 2005. ISUZU BEGAN MAILING OWNER LETTERS ON AUGUST 4, 2005. OWNERS MAY CONTACT CHEVROLET AT 1-800-630-2438, GMC AT 1-866-996-9463, ISUZU AT 1-800-255-6727, BUICK AT 1-866-608-8080, AND OLDSMOBILE AT 1-800-630-6537.

Estimated Vehicles Affected: 286478

Notes: GENERAL MOTORS CORP. 05044

[Jeremy airjer W]

I should do some homework before I type!

Just when you think you have it all figured out GM has to change it up. You guys are correct. The turn signal switch is now just an input to the flasher module. The flasher module looks for the signal and directs current flow to the correct side of the vehicle or if the four ways are on to all four corners. The turn signal switch basically does not control where the power is directed anymore!

And I thought it was over complicating things when ford decided to control the washer pump with the body control module!

[jwhjr]

Thanks for all of the input everyone. It looks like I'll probably try replacing the flasher module first since that is slightly cheaper, and a whole lot easier to replace then the multifunction switch. I'll report back once I do whether it takes care of the issue or not.

[Jeremy airjer W]

JW, hang on to that old part. I'd like to take a look at the inside of it. I'm down in cottage grove everyday maybe we can arrange something. Or toss it if your not interested!

[jwhjr]

I'll hold onto it for you. I'll probably get to this in the next few weeks.

[jwhjr]

airjer - any opinion on a NAPA flasher vs. a Delco one? If I remember correctly, you use a lot of NAPA parts. I can get the one I want for about $15 cheaper than a Delco one.

[Jeremy airjer W]

The nice thing about NAPA stuff is there are many times that it is the actual O.E. part with a NAPA sticker covering the O.E. one. I have run into this many times.

With that being said I had a stratus in the other day with a bad flasher. The first NAPA one didn't work at all, the second would blow the hazard fuse as soon as you turned them one, and the third came from the dealer (problem solved).

I vote for let you try it and let us know how it works!

[Jeremy airjer W]

I should also mention that if you crack that thing open you may find a simple issue that can be repaired without replacing. One of the reasons I would like to take a look. There are many times that I have repaired light out modules/ EEC power relays/ and flashers with a soldering iron.

[jwhjr]

I pulled the part out this morning and put the NAPA part in. So far the symptom hasn't happened, but I haven't done a ton of driving. There is now something else "weird" going on. When you hit the brake pedal (even when the truck is off), you can hear a click from the flasher relay even if no blinker/hazards are on. I triple checked that I have the replacement in all the way, but it's still happening. Bad module from NAPA, or symptoms pointing to the multifunction switch? And to your comment in the other thread airjer, I expedited this repair

[Jeremy airjer W]

lol!

[jwhjr]

I put the GM one back in and it doesn't click when hitting the brake pedal. I returned the NAPA one and have a GM one on order from Merit Chev, but it won't be in until next week. I'll give the GM one a shot and let you know what happens. I can get the dash apart pretty quickly now. Now if I could only muster up the energy to change out the 4x4 switch in the 99 Suburban...

[Jeremy airjer W]

The only thing I can see is that it also supplies voltage for the trailer lights/brakes. It may be a relay switching to supply brake power to the relay. Otherwise the brake lights for the vehicle bypass the module.

[jwhjr]

I put the GM one in today. So far so good. I'm heading up north later today so it will get a test on a nice long drive. No clicking when the brake pedal is pressed.

[Jeremy airjer W]

Sweet!

I told a co worker about GM's new plan. After I described what they are doing he said the same thing I thought when I read through this. Thank god I found out about it know before I arrogantly condemn the turn signal switch!!

[jwhjr]

After a trip up north and back and various other driving, I'm going to call this one fixed. Before I replaced it, it was acting up pretty much every time I was out and it hasn't since replacement. One thing to mention is that there are two replacement parts listed for the flasher. The direct replacement is labeled 2/4, and the other one is labeled 3/6. The 3/6 is for HD trailering or something like that. I replaced with the 3/6 because it was about half the cost of the 2/4. It blinks about 3x faster, but once you get used to it it's not a big deal. I'm guessing when I have trailer lights hooked up, it will slow down a bit because I noticed my other one would blink a little slower when towing. airjer, I still have the old one if you still want it to tear into and "fix". Just PM me and we can figure out how to get it to you.

[Hookmaster]

I think I saw you recently. A Silverado with the turn signal going like a bat out of hell.

[Jeremy airjer W]

That could have been any silverado with a turn signal bulb burnt out.

[jwhjr]

Where did you see it at hookmaster?