Problem with Daughter's car

[Homercidal]

I pride myself on being able to figure out and fix most things around the house, including our cars. This one has got me stumped, and I'm afraid the method for figuring it out is going to involve too much wire walking! It's a 1999 Regal and to be honest, not worth putting much money into, so I've been hesitant to spend mechanic prices for something that I *should* be able to diagnose!

Here's the problem:

Front turn signals don't blink. All filaments seem to light up, but when blinkers are turned on, they don't blink.

Both back turn signals blink. They blink fast, just as if you had a burned out bulb somewhere.

I've replaced all bulbs in the front.

I have replaced the multifunction switch for the turn signals and wipers (she also has intermittent issues with some speeds of the wiper not working sometimes, so I naturally assumed this would be a reasonable item to replace.)

On either turn signal or Hazard, the front flashers do not flash.

I'd consider replacing the flasher module, but for 2 things: First, they don't seem to stock them in our town, and second, flashers work on a side-by-side basis, not front-to-back. There are only 3 leads on that module, an input and 2 outputs (I assume) so if the backs are working I believe the fronts would be as well at that point.

If the fronts didn't light up as well, I'd consider there to be a ground problem, but the leads all test to ground, and the turn signal filaments do light up when the turn switch is activated.

 

[jbunton]

Could just be the relays. Gms are bad for dumb electrical stuff as they get old. Can u get another relay from an auto recycler?

 

[cegan09]

Clean and check all connections at the bulbs, and make sure the ground path is good. Some bulbs ground through the socket.

I'd still consider replacing the flasher unit. It could be dying. Speaking in pure theory, the wire runs to the rear are longer than the front usually. If the unit isn't fully clicking off the longer leads may have enough additional resistance to let the bulb go out while the fronts don't. But the chances of that do seem really slim. Still, if you have a good ground at all bulbs, new bulbs, and none of the wiring seems bad, what else is there?

 

[Homercidal]

I think the relay and flasher unit is the same thing. They cost about $15 and not too bad just to try, but it can't possibly be the flasher as the rear flashes and they are on the same output as the front, per side.

 

[Maylar]

There's a pretty active Buick forum here -

http://buickforums.com/forums/

I have a 99 Park Ave, I'll look in my service manual and see if there are any blinker troubleshooting tips.

 

[GilaMinumBeer]

Sounds like a flash relay to me.

 

[nDub]

Blinker fluid?

Loose nut behind the wheel?

Wiggle the wires?

I'm super helpful?

 

[NothingRhymesWithCurtiss]

I had a Buick LeSabre that had similar problems, and between my father and myself, we couldn't pin it down. I had my neighbor who is a mechanic take a look and he determined that due to how the car is wired, it all stemmed from my faulty cruise control. We fixed the cruise, and everything magically starting work again.

Not saying this is the cause of your troubles, but thought it was worth a mention.

 

[bob1852]

Fuse?

On my old Isuzu truck, a blown fuse would cause other things to happen (faster blinker, etc) as a warning that a fuse was out.

 

[passedpawn]

Blinker fluid?

Nice. I was thinking that or the grimature or perhaps muffler bearings.

 

[passedpawn]

Sounds like a flash relay to me.

Front left and rear left should be flashing off same relay blade. So if one was working, it's not the relay.

Sounds like both sides are doing the same thing, too, so that would be two relays involved.

 

[cegan09]

I think the relay and flasher unit is the same thing. They cost about $15 and not too bad just to try, but it can't possibly be the flasher as the rear flashes and they are on the same output as the front, per side.

It could. If the flasher is wearing out it may not be clicking off fully. I'm going to make up some numbers for a second. If normally the circuit runs on 12V, the bulbs are designed to work on some range. They will light up if they get lets say 8-14V. If instead of fully clicking off to 0V the flasher is now simply dropping to 8V from 12V, you could see what you're seeing. The fronts with the shorter wire have enough voltage to stay on, however the rears with the longer wire run have enough additional voltage drop to turn off, hence blinking and not blinking front to rear.

Again, I grant that the above seems like a really slim chance of being the case. But if you've already made sure the bulbs have good ground, the bulbs are new, the wiring isn't frayed and breaking, the fuses are all good, there aren't any other relays to be going bad, you're really left with nothing else to check.

 

[passedpawn]

I pride myself on being able to figure out and fix most things around the house, including our cars. This one has got me stumped, and I'm afraid the method for figuring it out is going to involve too much wire walking! It's a 1999 Regal and to be honest, not worth putting much money into, so I've been hesitant to spend mechanic prices for something that I *should* be able to diagnose!

Here's the problem:

Front turn signals don't blink. All filaments seem to light up, but when blinkers are turned on, they don't blink.

Both back turn signals blink. They blink fast, just as if you had a burned out bulb somewhere.

I've replaced all bulbs in the front.

I have replaced the multifunction switch for the turn signals and wipers (she also has intermittent issues with some speeds of the wiper not working sometimes, so I naturally assumed this would be a reasonable item to replace.)

On either turn signal or Hazard, the front flashers do not flash.

I'd consider replacing the flasher module, but for 2 things: First, they don't seem to stock them in our town, and second, flashers work on a side-by-side basis, not front-to-back. There are only 3 leads on that module, an input and 2 outputs (I assume) so if the backs are working I believe the fronts would be as well at that point.

If the fronts didn't light up as well, I'd consider there to be a ground problem, but the leads all test to ground, and the turn signal filaments do light up when the turn switch is activated.

Sounds like the front lamp returns have a short to ground somewhere up there. For example, I'm guessing that the relay is switching the lamp returns to GND (i.e., the relay doesn't source 12V to the lamps - that comes from elsewhere when the blinkers are turned on). I'd remove one of the relays, then check the load side of it to see if it ohms to gnd, then figure out where that short is. That's all a wild guess of course.

 

[GilaMinumBeer]

Front left and rear left should be flashing off same relay blade. So if one was working, it's not the relay.

Sounds like both sides are doing the same thing, too, so that would be two relays involved.

Looks like there is only a single relay involved. I think the issue is along the lines of;

It could. If the flasher is wearing out it may not be clicking off fully. I'm going to make up some numbers for a second. If normally the circuit runs on 12V, the bulbs are designed to work on some range. They will light up if they get lets say 8-14V. If instead of fully clicking off to 0V the flasher is now simply dropping to 8V from 12V, you could see what you're seeing. The fronts with the shorter wire have enough voltage to stay on, however the rears with the longer wire run have enough additional voltage drop to turn off, hence blinking and not blinking front to rear.

Again, I grant that the above seems like a really slim chance of being the case. But if you've already made sure the bulbs have good ground, the bulbs are new, the wiring isn't frayed and breaking, the fuses are all good, there aren't any other relays to be going bad, you're really left with nothing else to check.

^ this.

 

[Homercidal]

To add to the discussion I see now that this car has a "Daytime Running Lights" module. I will have to read up on this and check the schematic to see how that is wired in.

Have I ever mention how much I LOVE these fancy GM electronics?? This is not the first really weird problem I've seen with GM electronics.

At least the 3800 motor is holding up very well. Worse comes to worse, I can always just run new wires from the turn signal switch to the lamps. Nothing like bypassing an engineer's months of design work just to make it work right!

 

[Homercidal]

There's a pretty active Buick forum here -

http://buickforums.com/forums/

I have a 99 Park Ave, I'll look in my service manual and see if there are any blinker troubleshooting tips.

Checked the forums and no response yet.

I saw a 2002 Bonneville on sale for $2000 nearby. I'm half tempted to sell my daughters car and get her that one! (Or title the Malibu sitting in the driveway and let her have that one. Might help our place not look so much like a used car lot...)

Which reminds me I have to clean the turn signal switch on that car so it doesn't make the hazards click constantly. Did I say how much I LOVE GM electronics??