Page 1 of 2 12 LastLast
Results 1 to 10 of 17

Thread: DIY: How to repair a VW MK5 door lock module

  1. #1
    Join Date
    May 2016
    Location
    Melbourne, Victoria
    Posts
    157
    Users Country Flag

    Post DIY: How to repair a VW MK5 door lock module

    The mk5 door lock failure seems to be a common issue, but from what I can see there is very little info on how to actually fix one of them - rather than just replacing the whole unit. Of the 3 door locks that have failed in my 06 Jetta all 3 were due to the issue described in this DIY - this doesn't mean there aren't other ways they can fail, and so I have included some basic diagnosis steps. The DC motor issue was originally suggested by Saabman a while back in another thread and so thanks to him for making this DIY possible!

    Symptoms for this failure mode
    - Door intermittently locks and unlocks
    - If you listen closely around the door handle you should be able to hear some sort of sound when unlocking/locking the car. If after multiple attempts you can't hear anything it might be worth checking the door wiring harness first.

    Step 1

    Remove the outer door skin and the door lock actuator, this has been well described elsewhere so I won't go into that here, a good tutorial can be found at shopdap.com

    Step 2

    Now the lock is off the car we need to separate the two halves, there is a mechanical and electronic side - the electronic side will be the focus of this DIY. Start by removing the T20 screw.


    DIY: How to repair a VW MK5 door lock module-dsc_9500-jpg

    Followed by the smaller torx screw, I didn't have a bit this small but a 2mm flathead screwdriver seemed to work fine (it's not in too tight).

    DIY: How to repair a VW MK5 door lock module-dsc_9501-jpg

    Unclip the two tabs either side of the small torx screw, and pull this lever back. The two halves should now separate.

    DIY: How to repair a VW MK5 door lock module-dsc_9503-jpg

    Step 3

    Open the electronics side by undoing the 8x T10 screws circled below. Whatever you do, do not undo the T20 in the middle of the red lever, it isn't fun trying to put that back together when it springs apart!

    DIY: How to repair a VW MK5 door lock module-dsc_9507-jpg

    Step 4

    With the unit open, it is now possible to diagnose the unit. To check the motors, measure the resistance across the metal prongs attached to them - it can be difficult to get a good connection so some scratching of the metal may be required. The value across the larger white capped motor should be about 3-4 ohms, I have had it read 40-100 before repair. The small black capped motor seems to be reading about 20 in this case, but it may be due to the coating applied to the prongs. In any case, given the larger motor seemed off I just decided to clean out both since I already had the unit apart although it may only be necessary to work on the larger one. To check the microswitches use the continuity function on your multimeter. Touch the leads on the two outer pins of the switch, and depress the switch to check for switching - i.e. if it starts as continuous it becomes discontinuous when depressed or vice versa.

    Step 5

    If you are satisfied one or both of the motors is the cause, then the motor needs to be opened. The motor is held together by two metal tabs around the plastic cap. In order to open the motor I used a small flathead screwdriver and weakened the tabs by grinding part of it with a dremel as shown. The area of metal casing around the tabs does not seem too critical so don't stress too much about messing it up.

    DIY: How to repair a VW MK5 door lock module-dsc_9514-jpg

    After bending the tabs out of the way the plastic top should just slide out. Here is what you should expect to find (the smaller motor wasn't as dirty as the larger one). As for why the motors are so dirty I am not so sure, some on other forums speculate they may have been manufactured in dirty conditions or grease and oil may have somehow found their way into them during manufacture.

    DIY: How to repair a VW MK5 door lock module-dsc_9519-jpg

    Step 6

    In order to clean the commutator ring I used 2000 grit sandpaper followed by a wipe down with isopropyl alcohol. IPA was also used to clean the plastic housing and brushes. After cleaning, reassemble the motors, I applied a small amount of super glue to secure the plastic piece back on.

    DIY: How to repair a VW MK5 door lock module-dsc_9528-jpg

    Step 7

    Now reassemble the electronics housing. The top cover should fit easily onto the bottom - if it is sticking up something is probably misaligned. Here are a few things that you may want to be mindful of:

    DIY: How to repair a VW MK5 door lock module-dsc_9509-jpg

    a. Replace the rubber motor cover if you removed it when opening the motor
    b. Make sure the pin is sitting inside the groove of the plastic piece below it. Also check that the black plastic bushing at the end of the worm drive is present and seated correctly.
    c. Check the microswitch is positioned correctly. It should be either open as shown, or depressed by the white plastic piece to the right of it. It should not be sitting on top of the plastic piece.
    d. Ensure the arm is correctly located on both posts, and in this case it is depressing the microswitch.

    DIY: How to repair a VW MK5 door lock module-dsc_9530-jpg

    A reference photo of the lower section in case yours falls apart.

    Step 8

    With the electronics side back together the two halves can be joined again. Before mating the two halves, ensure that the position of the lever is the same as when you took it off the car. The two positions are shown below (in this case unlocked position was required). Failure to properly position it will result in the lock not operating. You can check proper operation by moving the lever to the lock position then pulling the lever that is attached to the interior door handle - the interior lever should kick the red lever to the unlocked position. Try this a few times to make sure nothing goes wrong.

    DIY: How to repair a VW MK5 door lock module-dsc_9541-jpg

    DIY: How to repair a VW MK5 door lock module-dsc_9542-jpg

    Join the two halves together and replace the two screws. In order to replace the spring I found the best way was as follows. Position the spring as shown below, then use a set of small needle nose pliers to force the long end of the spring over the tab.

    DIY: How to repair a VW MK5 door lock module-dsc_9540-jpg

    Summary

    The unit is now ready to install back into the car, I highly recommend testing the lock thoroughly including interior door handles for a few unlock/lock cycles, as some problems will only manifest on the second or third try. After you are satisfied everything is operating correctly, replace the door panel and handle.


    As for the longevity of repairs from this method, I am not 100% sure but can't see why they wouldn't last as long as it did originally (provided no other components fail) and have so far had one lock working flawlessly for 8 months. This repair is not too difficult, and I'd estimate the time to get the lock apart and back together again is about 15-30 mins, the time taken to separate the motors may take some time if you have never done it before but is possible to do in 5-10 mins.

    Hopefully this helps someone out!
    Last edited by MEL744; 20-08-2020 at 09:51 PM.

  2. #2
    Join Date
    Sep 2016
    Location
    Sydney
    Posts
    101
    Comprehensive write up! Nice work DIY: How to repair a VW MK5 door lock module

    Sent from my SM-G960F using Tapatalk

  3. #3
    Join Date
    May 2006
    Location
    Adelaide South Australia
    Posts
    1,278
    Quote Originally Posted by adey88 View Post
    Comprehensive write up! Nice work
    X 2.
    Mods. Could this thread be posted in the Mk5 FAQ & DIY section please?
    Understand how it works, troubleshoot logically BEFORE replacing parts.
    2001 T4 TRAKKA Syncro 2.5TDI,2006 Mk5 2.0TDI Golf manual,2001 Polo 1.4 16V manual [now sold], '09 2.0CR TDI Tiguan manual,
    Numerous Mk1 Golf diesels

  4. #4
    Join Date
    Apr 2007
    Location
    Adelaide hills, SA
    Posts
    9,708
    Users Country Flag
    Quote Originally Posted by jets View Post
    X 2.
    Mods. Could this thread be posted in the Mk5 FAQ & DIY section please?
    ...posted, linked in.
    Great write up.

  5. #5
    Join Date
    Feb 2015
    Location
    Sydney
    Posts
    5
    Users Country Flag
    Damn, I just bought a new lock module from ebay for $40

  6. #6
    Join Date
    Jul 2007
    Location
    Brissy
    Posts
    2,192
    Users Country Flag
    Quote Originally Posted by tommoe View Post
    Damn, I just bought a new lock module from ebay for $40
    I would say money well spent. How much do you value your own time? I think this would take more than $40 of my time to pull apart and repair.

    You got a link to the ebay item ?
    MK4 GTI - Sold
    MK5 Jetta Turbo - Sold
    MK5 Jetta 2.Slow - Until it dies.

  7. #7
    Join Date
    Apr 2007
    Location
    Adelaide hills, SA
    Posts
    9,708
    Users Country Flag
    I think he might’ve been sarcastic.
    Though, I wouldn’t have much faith in the $40 door module from eBay. The part could’ve been from the raided VW rubbish bin. Or what was rejected by VW and somehow find the way to the eBay.

  8. #8
    Join Date
    Feb 2015
    Location
    Sydney
    Posts
    5
    Users Country Flag
    Quote Originally Posted by Transporter View Post
    I think he might’ve been sarcastic.
    Though, I wouldn’t have much faith in the $40 door module from eBay. The part could’ve been from the raided VW rubbish bin. Or what was rejected by VW and somehow find the way to the eBay.

    No sarcasm, yeah you're right it's probably a knock off though!

    REAR LEFT DOOR LOCK MECHANISM For VW GOLF MK5 7 Pin Actuator 3D4839015A Black yD | eBay

  9. #9
    Join Date
    Apr 2007
    Location
    Adelaide hills, SA
    Posts
    9,708
    Users Country Flag
    Quote Originally Posted by tommoe View Post
    No sarcasm, yeah you're right it's probably a knock off though!

    REAR LEFT DOOR LOCK MECHANISM For VW GOLF MK5 7 Pin Actuator 3D4839015A Black yD | eBay
    Not a knock off, it’s what the Volkswagen rejected as not meeting their quality standard.


    Sent from my iPad using Tapatalk

  10. #10
    Join Date
    Aug 2014
    Location
    Melbourne
    Posts
    84
    Users Country Flag

    After spending tons of money getting 3 of these done, on the 4th breakage I bought a $32 one from ID Parts. Installed it two years ago and still works like a charm (albeit every time i get it serviced i'm told it throws an error code) Its a fun DIY replacement to do and lets you clean out everything in the doors.

Page 1 of 2 12 LastLast

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
| |