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Discussion Starter · #1 ·
I have an 04 passat with a v6. My #34 fuse will blow the second the ignition is turned on. The car runs normal except for a rough down shift and if the car is under 3300 rpm's the car will jerk or shutter at 36mph and 66mph. I have taken it to 2 shops and they can't find the problem. The traction control light is on and the check engine. When they pull he codes over 26 problems print out. Any help on this subject would be helpfull.
 

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Fuse 34 provides positive to a lot of equipment including secondary air injection valve, SAIP relay, MAF, your 4 O2 sensor heaters, the 2 camshaft adjustment valves, EVAP valve, leak detection pump, and change over valve. That's why you have all those dtcs. Positive to fuse 34 comes from the fuel pump relay contact. So I believe the relay picks up when the ignition is turned to on but not started. Does the fuse blow as soon as you turn the key to on but not to start? If that's the case then it should be relatively easy to isolate the problem by disconecting all the equipment and start plugging the connectors back in one at a time until the fuse blows. It also could be a short to ground in the engine wiring harness.

Also, look for any pinched wires in the wiring harness.
 

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I have 2000 GLS V6 with 70000 miles, having identical symptoms (jerking, rough idle, sometimes stalls out) with blown fuse #34 except doesn't always blow immediately on ignition. Sometimes fuse has lasted for one month since problem first occured about 3 months ago. Dealer unable to trace problem to single source.

They told me VW tech support's suggestion was to install individual fuses on each device supported off this fuse. Estimated $1000 just to identify the cause! Then cost to repair.

Also have ABS module failure issue at same time so the alarms are always "beeping"!

Have you solved your problem or any other suggestions out there? Is it harmful to continue driving with this fuse blown?
 

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Discussion Starter · #5 ·
The lights are still on and since then the pulley guide for the timming belt froze. I brought it to the shop and they fixed that for $1100.00 but still can't find my fuse problem. I came home today and the brake switch went out. I took it out and read some other forums that this can cause the esp and the check engine light to come on or stay on. I'm curious if this has been causing the problem.
 

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Discussion Starter · #6 ·
Sorry I took so long to reply. My new post shows that I still have the problem, but now the brake switch went out today. I read this will cause the ESP and Check engine lights to stay on if it is shorted. Do you think this can help. I own 93 mustang 5.0 and it has been more reliable than the passat. Do you know where I can get a diagram or something to point out the sensors you listed. The local shops will not touch my car and the dealship is 4 hours away.
 

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You buy a good one, it's great! You have one go bad, it's bad...

The Passat is a very complicated car when it comes to it's electronics and electrical systems. Diagnosing electrical glitches is a real time-consuming job, which is why it ends up costing so much. Your best bet would be inspect all the wiring harnesses, especially the ones by the firewall. Look for plastic connectors or wire-ends that look a little brown or black, where they've been burned. Also, have all the grounding points checked to make sure they're still properly grounded.

Failing that, you basically have to measure and troubleshoot one system at a time.
 

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Discussion Starter · #8 ·
Fuse 34 Cont.gg

My brake switch part came in. I used the parts train. I was really pleased with the time for delivery and the part was a OEM. The brake switch fixed the brake light staying on but not the fuse 34. The minute I turn the key on the fuse blows. My ESP light and Check Engine Light is still on. I would like a diagram to find all the parts connected to this fuse.:banghead:
 

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Discussion Starter · #10 ·
Fuse 34

:angel: I think I just found the F..ING, as in FREAKING!!! problem!! A pinched wire on the passenger side black 4 pin plug on firewall. Locks like it could have been factory done and it took time to wear through! I'm relieved and mad at the same time.
Thanks to all of you for your advice!!
 

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Discussion Starter · #11 ·
I fixed the problem today. I unplugged all connections and went one by one plugging it in than turning on the ignition. I repeated this until the fuse blew. On my passat I found the Black 4 pin plug on the passanger side firewall was the cause. The plug had 3A0 9733 304 gsm2 and PA6.6 stamped on it. I followed the wires back to a bracket under the air intake mounted to the back of the head. There I found the wire was pinched and had wore through the plactic and web casing to the wire shorting it out. The car as far as I know has never been touched in that area. The nut had to be loosened before I could free it. Hope this helps other people and thankyou all for your suggestions and help..
 

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Good job. If the connector was black 4-pin, then it was the O2 sensor plug that goes to the sensor before the cat converter on bank 1 (passenger side). If you have never had that O2 sensor replaced, then it probably was a factory installation problem.
 

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Fuse 34

👼 I think I just found the F..ING, as in FREAKING!!! problem!! A pinched wire on the passenger side black 4 pin plug on firewall. Locks like it could have been factory done and it took time to wear through! I'm relieved and mad at the same time.
Thanks to all of you for your advice!!
Where can I find this on my car because I am having the same exact problems as you, if u want to check out my thread called(harsh jerking) that would help also, but where would I find this pin because I have not replaced my cats yet but this randomly happened out of the blew…
 

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Where can I find this on my car because I am having the same exact problems as you, if u want to check out my thread called(harsh jerking) that would help also, but where would I find this pin because I have not replaced my cats yet but this randomly happened out of the blew…
I doubt they will reply. It has been 15 years since they have been on this site.

That said, the 4-wire plug they speak of is on the firewall snapped onto a plastic bracket that holds another plug or two. Driver side, I believe.
 
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O2 sensor plugs - This applies to the V6

There are (3) 4 wire plugs on the passengers side of the car on the firewall.
Green, Brown and Black

There is (1) 4 wire plugs on the drivers side of the car on the firewall.
Black
 
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