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Discussion Starter #1
So I've been chasing this problem since I purchased the car but fuse 22 keeps blowing for right side running light on my brake light.i hsve searched the forum and tried most things other people have said. I am a standstill now. It just keeps popping as soon as you hit the light switch. Thing I have tried with no success are :
Unplugging taillight and headlight - still pops
Replaced light switch
Checked ground for taillight and is good.

Just not sure what other switches or anything that might be a culprit.
 

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With the 12V battery disconnected and the offending light bulb removed, measure the resistance from the output of the light switch (the connector that goes to the offending light) to ground when the switch is on. It should be an open (infinite resistance). I'm guessing it won't be. If that is the case, you need to trace the wire from the switch to the light socket and find the spot where it is shorted to ground. A schematic would help a lot of course, since then you can break the connection in the middle and divide the problem in half. Keep doing that until you find the problem then fix the wire. Hopefully FrescoGreenWagon will chime in since he's a real pro at deciphering the VW electrics.
 

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As far as I can tell, fuse #22 only goes to 2 lights, the front side marker and rear tail light on RHS.
So there must be a short in one of those 2 wires.
It can be caused by an incorrectly fitted tail light bulb, but you eliminated that by disconnecting the tail light.
 

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Discussion Starter #4
As far as I can tell, fuse #22 only goes to 2 lights, the front side marker and rear tail light on RHS.
So there must be a short in one of those 2 wires.
It can be caused by an incorrectly fitted tail light bulb, but you eliminated that by disconnecting the tail light.
Dumb question, when we talk about the side marker are we talking about the signal light in the headlight bulb or the one on the fender ?
 

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It is a small low wattage bulb in the outer part of the front light assembly. Switch the lights to the first click and check the left side.
If you have a side marker in the fender that would also connect to fuse #22.
 

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Depends on what year it is. In the US, we had side marker lights on the fenders for the 98-03 models.
 

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For this conversation, we're talking about the low-wattage filament in the front turn signal lamp (mounted in the headlight), the small 5-watt bulb located in the high-beam reflector, and the low-wattage filaments of the tail/brake bulbs.
The small lamp on the fender (thru MY'03) is a turn signal, not a sidemarker. It's part of the turn signal circuit.

If fuse 22 blows with both the headlight, and the tail light physically unplugged, then the fault is in the vehicle wiring, or in the headlight switch itself.
 

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Discussion Starter #8
It is a small low wattage bulb in the outer part of the front light assembly. Switch the lights to the first click and check the left side.
If you have a side marker in the fender that would also connect to fuse #22.
For this conversation, we're talking about the low-wattage filament in the front turn signal lamp (mounted in the headlight), the small 5-watt bulb located in the high-beam reflector, and the low-wattage filaments of the tail/brake bulbs.
The small lamp on the fender (thru MY'03) is a turn signal, not a sidemarker. It's part of the turn signal circuit.

If fuse 22 blows with both the headlight, and the tail light physically unplugged, then the fault is in the vehicle wiring, or in the headlight switch itself.
It will have to be in the wiring then. I'm assuming I will be able to easily see when tracung this wire where the issue is?
 

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Not too easily, I'm afraid. You'll need to inspect the wiring harness, front to rear, looking for chafing, pinching, screw penetration - things like that.
First, though, grab thy DVOM. With both front & rear lights disconnected, see if you have continuity to ground at the pin for the right side lights (sorry, no book in front of me right now, to see which pin) - with the lights unplugged (and the switch removed, of course), it should be 'open.' If it is, fault is in the light switch.
 

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Trying to find a short can be easy or it can be really tough. Be patient and thorough and you'll get there. The best approach is divide and conquer and to use the process of elimination. cuppie's advice about the light switch test is a good place to start. If it's not the switch, it's in the wires and could literally be anywhere along the path although places that are exposed to abrasion or penetration are more likely.
 

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Discussion Starter #11
I retried doing it while unplugging the rear light and tried both rear sides and it only pops when the taillight is plugged in. Light switch is new and shows no problems.
 

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What happens if the tail light is in but the running is out?
It sounds like the light socket may have a problem but it could be anything at this point.
 

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OP, is your car a B5 or B5.5 (facelift)? The B5.5 (production dates from Oct 2000, one-piece headlights) have a separate side marker light front and rear, in the bumper covers, in addition to the headlight and taillight assemblies.

The front one I remember is virtually inaccessible from behind. You press in one end of the light against a spring, then slide the whole thing towards the rear (as I recall) of the car and it comes right out.

The headlight switch is not your problem. Odd as it seems, the lighting fuses are downstream of the headlight switch. One contact on the headlight switch switches power to fuses 4, 22, & 23, as well as the cluster.
 

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Discussion Starter #15
OP, is your car a B5 or B5.5 (facelift)? The B5.5 (production dates from Oct 2000, one-piece headlights) have a separate side marker light front and rear, in the bumper covers, in addition to the headlight and taillight assemblies.

The front one I remember is virtually inaccessible from behind. You press in one end of the light against a spring, then slide the whole thing towards the rear (as I recall) of the car and it comes right out.

The headlight switch is not your problem. Odd as it seems, the lighting fuses are downstream of the headlight switch. One contact on the headlight switch switches power to fuses 4, 22, & 23, as well as the cluster.
It is an 03. I have tried it with that light as well but I get no running lights whatsoever. It does work as a turn signal though.
 

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You need a new tail light bulb assembly if it pops the fuse when plugged in and nothing else plugged in. Same thing happened to me. Went to the junkyard and pulled one to replace it. If I am understanding your findings, of course.

Try plugging in the right tail light assembly into the left wiring and see if it still pops the fuse.
 

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It is an 03. I have tried it with that light as well but I get no running lights whatsoever. It does work as a turn signal though.
The "repeater" turn signal in the metal fender, just in front of the front doors, isn't what I'm talking about. It is only on the turn signal circuit.

The two lights in question are are located in the front and rear bumper covers (on each side). One could easily mistake them for reflectors. Those two lights remain in the circuit even when the headlight and taillight assemblies are unplugged.

I need to find the pictures of my retired Fresco Green 01.5 Passat--you could see them there.
 

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Discussion Starter #18
You need a new tail light bulb assembly if it pops the fuse when plugged in and nothing else plugged in. Same thing happened to me. Went to the junkyard and pulled one to replace it. If I am understanding your findings, of course.

Try plugging in the right tail light assembly into the left wiring and see if it still pops the fuse.
This is what I tried yesterday and still popped fuse unfortunately. And seemed to work when on the other side.
 

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Discussion Starter #19
The "repeater" turn signal in the metal fender, just in front of the front doors, isn't what I'm talking about. It is only on the turn signal circuit.

The two lights in question are are located in the front and rear bumper covers (on each side). One could easily mistake them for reflectors. Those two lights remain in the circuit even when the headlight and taillight assemblies are unplugged.

I need to find the pictures of my retired Fresco Green 01.5 Passat--you could see them there.
When I got the car originally there were no marker lights on the front. I will have to look at the rear as well.
 

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The two lights in question are are located in the front and rear bumper covers (on each side). One could easily mistake them for reflectors. Those two lights remain in the circuit even when the headlight and taillight assemblies are unplugged.
D'oh! I forgot about the sidemarkers / reflectors. Yes, those are also part of the side lights circuits.
 
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