Thread: MY12 D4 - individual doors not locking or unlocking

For anyone reading this in the future, a year and a bit later and only two out of the three AliExpress replacement units work consistently. The third one requires you to unlock up to 10 or so times before it unlocks the door allowing you to open.

I still have the original units which I’ve been planning to try and open up to clean inside as per kenl’s earlier suggestion.

I used a Britpart one that only lasted two years. It’s now flaky. I’ve ordered a genuine as a replacement as they last longer. Also the copy didn’t have the same mechanical feel as the genuine and made it feel cheap.
I’ll fit the new one next week.

Ive got an e-bay sourced drivers side locking module sitting in my garage ready to go in as the original one was playing up and actually logged a code.

I reckon the car knows its there as its been behaving itself since it arrived, I guess she doesnt like having her door interiors interfered with....

Have checked that power is reaching the actuator? I'm not familiar with D4s, but in Defenders there is a wire running through a rubber sheath to the doors which can get pinched and stop power reaching the actuator. Might be worth checking. Just a thought.

I have had both rear passenger doors fail. Three years ago the RH door wouldn't lock except by manually shutting the lever and then it only unlocked manually. The Stealer charged me $500 to fix it. The LH door failed about a year ago and now works intermittently - I haven't bothered to fix it. We don't use it very often and not at all the past six months of lock-down/isolation. One day, if we are allowed out of home (Melbourne), I might have a go at cleaning the actuator - it still tries to open electrically.

Originally Posted by kenl

It is not so much that the the brushes go, they just gunk up, I pulled one apart and cleaned up the brushes about 5 years ago and it is still going, in the mean time the replacement actuator (bought on aliexpress) still sits in the drawer.

Exactly. These motors never do more than about 10 revolutions in either direction and never get up to any form of speed that would throw gunk off the commutator. They also spend a lot of time powered while stationary and often across commutator segments where they cause a bit of arcing. Think already locked but trying to lock or vice versa. This causes quite a bit of carbon to be ejected from the brushes and the commutator to grunge up as there's never enough motion to clean it off.

Pulling the end bell off the motor can be a challenge the first couple of times. I generally unpick the peened sections as best I can and then push on the gear until it pushes the bell off.

I strip them down, clean everything thoroughly with isopropyl alcohol, polish the commutator if required, lube the front bearing with some ISO 32 synthetic oil and the rear shell (where the shaft sits in the nylon end bell) with some specific plastic rated grease. I've never had to re-do one. The lubrication is probably over the top, but I already have the stuff so it's a case of "why not?".

I've only had to do 2 on the D3, but done heaps on VW golfs. Same deal. Same motor except the shaft is longer on the Disco units.

I also found a source for the motors and bought 4 just in case, but haven't had one fail again after reworking it.

I bought motors at one point but couldn’t swap the gear over successfully. I’ve since seen them supplied with gears which would be easier.

Originally Posted by DiscoJeffster

I bought motors at one point but couldn’t swap the gear over successfully. I’ve since seen them supplied with gears which would be easier.

I have a specific gear puller set for that particular shaft size. I couldn’t find them with the right sized gear. Not that I’ve had to use the spares yet anyway.