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Door wiring harness -cracked wire replacement - mk5 VW
How to repair a broken or cracked door wiring harness on VW Jetta or Golf (Rabbit) 2005-2010, Sportwagen 2009-2013difficulty: 1/5
This DIY article shows how to repair or replace a cracked door wiring harness on a mk5 Volkswagen Jetta TDI. It also applies to mk5 Rabbit (Golf), GTI, GLI, or other similar mk6 models like the VW Sportwagen TDI.
A recurring problem on VW for multiple generations is broken wires in the door wiring harness connection. As the door opens and closes, the wires bend and over 100,000 miles or so, the insulation wears down and the wires short or the wires break. This can cause strange problems with opening and closing, the door and windows, the alarm, and opening the trunk and fuel cap door. The driver's side harness is the most vulnerable since this is the door most often used.
If this is a Canadian car and model year 2006, there was a class action suit which got VW to reimburse for past repairs on this and extend the warranty on this part to 8.5 years/ 165,000 kilometers. As of fall 2014, there was a class action settlement for this on 2005.5-2006 models which extends the warranty on this part to 8.5 years/100,000 miles and reimbursement for past repairs. Please refer to this forum thread for any updates on this: http://www.myturbodiesel.com/thread...n-lawsuit-settlement-reached-2005-2006.26408/
The best solution is a new wiring harness. The correct part number goes by the VIN number since different equipment levels/build dates required different harnesses. The replacement harness will be slightly longer. VW fixed this issue by lengthening the harness where it bends so this problem wasn't be as common on the newer years. Below is a pic from clickman showing the difference (thank you clickman!)
The Sportwagen used the mk5 chassis until 2013 even though it got the mk6 bumpers/headlight/2010 electronics in 2010. Please note, all newer Jetta/Golf/Sportwagen used the new style harness from the factory.
T20, T30 torx bits
Soldering equipment or new harness
Repair procedure for inspecting or repairing broken door wire harness on VW Jetta or Golf
For support on this topic, please post in this forum thread.
To check for a broken wiring harness or check the state of your wiring harness, open the door and have something hold it in case the wind blows it shut. There's a mechanism to hold it open but a strong gust of wind could still move it. Make sure the window is rolled up before you unplug the battery. Unplug the negative cable on the battery. See 1000q: battery removal if you need more details.
Grab the rubber tab at the top of the boot and firmly press it up to release the hook down. Once the hook is down you can lift the boot a little and pull it back to expose the plug. The bottom has a little lip which hooks over the bottom of the door hole. The plug has an orange lock lever - rotate it to unlock and push the plug back. From here you can inspect the wiring harness for cracks.
Below middle is some more detail on the hooks that hold the rubber boot. Below right is some more detail on the door side of the boot. You must remove the door skin to get the boot completely off.
Here's a better view after removal showing the broken insulation on the two thicker wires. There isn't much clearance so if you want to expose a lot of the wiring you have to remove the exterior door skin. See 1000q: door skin removal for details.
It should look like this. Here you can see the areas of interference where you should apply some tape to protect the door skin from scratches.
This will expose enough of the cracked wiring harness so that you can repair it as necessary. The wire harness gets close to the window rail so it has some thick padding wrapped around it there. If you need to replace the harness, see below.
Although the mk5 and mk6 Jetta, Golf, JSW, GSW (sportwagen) all have 5 star side impact ratings, I hope that seeing how little "armor" is in the door should shatter the illusion of cars as tanks and encourage defensive driving practices.
Replacement procedure for broken door wire harness on VW Jetta or Golf
If you wish to replace the door wiring harness, also remove the interior door panel. See 1000q: door card panel removal for details. The white box on the right is the door lock module and can also cause symptoms with locking/unlocking the doors. If the door doesn't seem to know that it was opened (from interior lights or alarm symptoms), and the wiring harness is fine, it's possible this is the problem. Please post in the myturbodiesel.com forum for more troubleshooting steps.
My wiring harness had the part number on a paper tab. The white tab is visible at the 1 o'clock position relative to the speaker. You can use this to find the correct replacement. The correct replacement has the same part number. If you're buying it from a VW dealer they can give you the correct part number using your VIN number.
Unplug the door lock module, window motor, side view mirror plug, and other plugs. The green clips hold the wiring harness in place.
On the other side of the door (the exterior side), there are 2 plugs - one for the side airbag and one for the lock module. The side airbag sensor plug has a blue lock tab which must be pressed in to release the plug. I just removed the sensor (2x torx screws) to make it easier to press the lock tab. If you're not sure how to release any plug, refer to your new wiring harness.
Installation is the reverse of removal.