Signal Problems

xwing79

Member
This is my first post, need a little help with my turning signals. I've got a 2002 P5 and haven't had any electrical problems until now. Last night I noticed that my turning signals on the left side of my car don't work. Both front and rear signals as well as the left turn signal indicator on the interior control panel. The right signals work fine, just not the left. My headlight and tail light on the left side work, just not the turning signals. I looked in the manual and can't find a specific fuse for the left turning signals so I'm not sure if that's the problem or not. I've got the weekend to figure something out before I have to take it in to the dealership and get shafted, so if anyone has any ideas they'd be much appreciated.
 
I'm thinking, a fuse or a relay. call me captain obvious! If you figure it out, be sure to spread the info.
 
xwing79 said:
This is my first post, need a little help with my turning signals. I've got a 2002 P5 and haven't had any electrical problems until now. Last night I noticed that my turning signals on the left side of my car don't work. Both front and rear signals as well as the left turn signal indicator on the interior control panel. The right signals work fine, just not the left. My headlight and tail light on the left side work, just not the turning signals. I looked in the manual and can't find a specific fuse for the left turning signals so I'm not sure if that's the problem or not. I've got the weekend to figure something out before I have to take it in to the dealership and get shafted, so if anyone has any ideas they'd be much appreciated.

You're talking the one that is a part of the headlight isn't flashing, right? Not the bumper one.. those just light up, never flash.
 
Kansei said:
You're talking the one that is a part of the headlight isn't flashing, right? Not the bumper one.. those just light up, never flash.

Neither turn signal is working. They don't even light up, much less flash. That's what led me to believe that it's a fuse, but I couldn't find one that controls just the left turn signals.
 
if the bulb for the turn signal in the headlamp was dead, the lights would flash very quickly.

It does sound like a fuse or relay, but like you said it doesn't seem logical that there would be separate fuses and switches for the left and right side. If I wasn't at work right now I'd run out to my car and scope things out for ya, but alas I'm stuck in the office for another couple hours.
 
Kansei said:
if the bulb for the turn signal in the headlamp was dead, the lights would flash very quickly.

It does sound like a fuse or relay, but like you said it doesn't seem logical that there would be separate fuses and switches for the left and right side. If I wasn't at work right now I'd run out to my car and scope things out for ya, but alas I'm stuck in the office for another couple hours.


Thanks man, let me know if you come up with anything. My brother-in-law seems to think it's a common wire between the two signals and the control panel indicator. I'm hoping it's not because that could be really expensive...
 
The turn signals are hooked to the HAZARD (15A) Fuse in the main fuse box under the hood on the driver's side. However, if the fuse is blown, no signals will work at all. What happens if you turn on the hazard button? Do both sides blink? If so, then it is likely a bad turn signal switch. If not, it is likely a bad flasher control module. This is, of course, assuming that you have verified that it is not a bad bulb.

Go here for reference: http://protege5.ugly.net/09-18.PDF page 16
 
wildo said:
What happens if you turn on the hazard button? Do both sides blink? If so, then it is likely a bad turn signal switch.

Also the wires to these switches tend to attach through a sort of clamp that goes over a spade that sticks out of the switch. (I'm sure that clamp has a real name but I can't recall it at the moment.) In some environments that sort of connector can fail - it's still in place but a layer of crud builds up between the metal contacts so the switch no longer works. My point being that if you narrow it down "to the switch" through the suggested test you really want to try cleaning those connections before replacing the switch. I had to replace a turn signal on a Honda once and it was unpleasantly expensive. Far cheaper to just clean the contacts if that will do the trick.
 
I guess the thing that is most puzzling to me is that the indicator on the control panel doesn't light up either. That makes me think it has something to do with the stalk. Is this a hard thing to fix on your own or is this something that I could do that the dealership would shaft me for?
 
Well, the turn signal lever is just a switch. It doesn't necessarily have to do with the light turning on. The whole system (exterior and interior signal lights) is powered through the 15A HAZARD fuse. Have you performed the "hazard test" mentioned above? What happens? If the left lights still don't come on then it is probably not the lever, it is probably the flasher control module... Either way- both items should be pretty easy to do yourself, assuming you are a bit mechanically/electrically inclined
 
Anybody have any ideas? I just started having the same problem recently, my whole left side signals do not work.
 
I see that this is an old thread...

Has anyone figured out the fix for this? My wife's car has the exact same symptoms...and it is also only on the left.

Someone...Anyone...please, help!
 
so.... did you try the flashers?

If they work - change the switch stalk (verrrry easy). Buy new (not used) - since it seems to perhaps be a latent defect in the switches...
 
so.... did you try the flashers?

If they work - change the switch stalk (verrrry easy). Buy new (not used) - since it seems to perhaps be a latent defect in the switches...

thanks for responding P-Funk.
So, it's either a bad Flasher Relay $58 (approx.) or a bad switch stalk $30 (approx.). When I put on the hazards the left side still doesn't come on, which I would think cancels out the switch stalk being the prob. So I'm leaning more toward the relay....any thoughts? Is there a way to check the relay before ordering one?
 
Same relay powers either side - so if the right is okay - then i am pretty sure it is not the relay....

You can also swap the relay with another of the same part number (there are usually a few like/similar in the panel)...

Check both front and rear bulbs. Not impossible that one went out and then the other and you didn't notice...
 
Same relay powers either side - so if the right is okay - then i am pretty sure it is not the relay....

You can also swap the relay with another of the same part number (there are usually a few like/similar in the panel)...

Check both front and rear bulbs. Not impossible that one went out and then the other and you didn't notice...
i disagree my buddy had a jeep cherokee that only 1 side was working we replaced the stalk and same issue we replaced the flasher and problem solved... my money is on the flasher relay
 
thanks for responding P-Funk.
So, it's either a bad Flasher Relay $58 (approx.) or a bad switch stalk $30 (approx.). When I put on the hazards the left side still doesn't come on, which I would think cancels out the switch stalk being the prob. So I'm leaning more toward the relay....any thoughts? Is there a way to check the relay before ordering one?

So after examining the wiring diagram:

FlasherCircuit_zpse39b51fa.jpg



I'm 97% sure that you have a Flasher Control Module issue. The control module isn't just a simple relay (or two). It is most likely an integrated circuit that uses solid state power switches (triacs or something like that).

However,... it could be just a bad connection at terminal "D" (the green wire with a black stripe) or a bad connection somewhere between that terminal and the bulbs.

You can test for 12 Volts at terminal "D". Leave the Module plugged in and test at the back of the connector. (it will be pulsing, so it will be a bouncing voltage on your digital voltmeter).

If you have a pulsing voltage, then there is a problem on the wire somewhere (or even the bulbs)

If you have no pulsing voltage, try unplugging the module and cleaning the terminal "D" connection. (maybe just plug it in and out a few times).

If you still have no voltage then you can be pretty sure your Control Module is shot.

FlasherControlmodule_zpsc69039da.jpg





If it were me,... I'd go score one off a junker for 5 or 10 bucks.
 
Last edited:
DD (diagram dude) - You da' man!

Yeah, after viewing this - i would buy a used flasher control module (most people don't have issues with them/good used part candidiate) and unless there was an accident/wiring repair - it is unlikely to be a wiring issue...
 

New Threads

Back