Central locking problem

[oldskewel]

Regarding the "master switch," is that the driver's door window control console? I know that so much runs through that, that calling it a master switch would make sense. In fact, when I installed my (turned out to be) faulty DLA, I accidentally dropped that window switch cluster on the ground when something suddenly required me to have an extra hand that I did not have. When I had weird behavior following the install there, I was not sure if it was the DLA or that switch cluster. Since it mostly worked, I did not worry about it until recently.

Unlike the DLA, that window switch cluster can be removed all by itself using nothing but your fingernails. It might be useful to see how the system responds now, when things are working fine, with that removed. Then you'll better know how to interpret the change when the problem is present.

Actually finding the failed part can be difficult. So when I was doing this last month, I first took the window switch cluster apart (having read many reports on here), inspected, hoping to find clearly visually failed solder joints. Only found one suspect, fixed it with no change.

Next easiest thing, while putting off serious fault isolation debugging, was to buy a replacement switch on eBay, which I did, with no improvement. It actually worked worse, which was puzzling. Then with the good DLA reinstalled, both eBay and my original window switch clusters worked fine.

So at that point, I spent a couple of hours doing serious, careful, experimental-mode testing with the INPA and Foxwell. Isolated the fault to the DLA, mechanically repaired my old one (plastic bracket had cracked and initial quick repair attempt did not hold), and swapped it in for the win.

[timmyc]

Originally Posted by Siddy1200

Thanks guys I will try disconnecting the drivers DLA next time it happens.

Just to be clear, I am talking about the master window switch, not the DLA. The switch in the door panel that has the controls for the windows and side view mirrors.

[Siddy1200]

Fixed! (Update: see new post bellow, problem came back after it rained, wet cables in the rear passenger door)

Hi guys I am reporting back to let you know that I found the problem and was able to fix it.

Oldskewel was right, it was the driver's door actuator at fault.
I followed his write up on how to repair it, one of the motors was burnt out. The brush cap was totally black. I bought a new motor and swap the brush cap over to the original motor.
Oldskewel's thread: https://xoutpost.com/bmw-sav-forums/...or-repair.html

It's a pretty involved fix, it was almost too difficult for me to put the actuator back together. I wouldnt recommend it, but in my case I had to pull it apart to make sure it was causing the problem.
EDIT: Where Oldskewel said to replace the drilled out rivets with machine screws, I used M3 screws. I bought an M3 tap and a 2.5mm drill bit. I had to cut the screws to size and use some M3 washers.

I now understand the issue I was having.
The burnt out motor created high resistance and this dropped the voltage supplied to the door locks. The front doors had 13v but when pressing unlock, the voltage at the rear doors went down to 7v. It was an intermittent fault because sometimes the 7v is just enough to unlock the door but sometimes not. With the repaired actuator back in the car the voltage when unlocking only goes down to 11v and the doors unlock with a nice strong clunk.

If you think you might have the same problem as me I will tell you an easier way to check for sure without disassembling the door lock actuator.
Remove the door card and peel back the vapour barrier.
Disconnect the connector to the door lock actuator.
Now test your central locking.
With the driver's door lock actuator disconnected, the rear doors and trunk should still lock and unlock just fine.
I could also notice that the noise the locks made we're loud and strong but with my faulty door lock actuator connected it was quite, weak and intermittent.

[chasers36]

I've had issues with my rear locks from the beginning when i bought my X5 a year ago, and just within the last 2 months my front passengers door lock has been on the fritz.

Central locking and the remote key fob will lock the rear doors just fine, but will not unlock them at all.

I've used BMW Scanner to scan for errors, and it produces 2 errors for my front passengers door lock, stating its short circuited, and the other just says malfunction. BMW scanner however does not produce any errors for the rear doors malfunctioning in anyway.

I'm assuming I should just go ahead and replace my front passengers door lock actuator, and see if that will solve my rear door not unlocking. Or am I also safe to assume that the motors that unlock the rear doors are just shot in both lock actuators, and I should most likely just need to replace those as well?

[Siddy1200]

Hi Chase,
It's unlikely all your door actuators are failing.

As I described in my post above, the resistance from 1 faulty actuator can drop the voltage for all doors and this causes other doors to have problems.

In my car it was the driver's door actuator that was faulty however the issues was that the rear doors sometimes wouldn't unlock. The driver's door seemed to work fine. Also I will note I could hear some of the locks struggling to lock and unlock, this was a hint the voltage was too low.

You should assume it's the driver's door actuator as this is by far the most common as it gets the most use. So start your diagnosis here.

I've got an easy way for you to test the driver's door actuator that I just found out by messing around today.

The driver's door actuator gets its power from the window switch block in the door. So, pull the window switch housing up and out of the door with some plastic pry tools. Then disconnect the 3 connectors. Now try your central locking.
If you had the same problem as me what will happen now is:
1. The driver's door lock doesn't respond (because it no longer has power).
2. All the other doors and the trunk work perfectly!!.

This diagnoses the problem being the driver's door actuator.
You can replace it or try to fix the motor as Oldskewel showed us, but I warn you it's pretty bloody difficult. Also, a second hand unit will probably be faulty and won't last long.

[Siddy1200]

So if anyone is following along I will just add a final note to do with assembling everything after the repair. I was pull what's left of my hair our trying to hook everything back up because it seemed like my freshly repaired door actuator wasn't getting power. Turns out I needed to plug the window switch block back in as this gives power to the lock actuator.
I also had to disconnect the battery for a minute, I don't know why?
And finally, to test if the door was locking properly, I had to close the door. I was using a screw driver to simply close the latch but this isn't good enough the door has to be completely closed.

So in short, if you put your door lock actuator back and it isn't working:
Connect the window switch block
Disconnect the battery for a minute
Close the door properly

[chasers36]

Originally Posted by Siddy1200

Hi Chase,
It's unlikely all your door actuators are failing.

As I described in my post above, the resistance from 1 faulty actuator can drop the voltage for all doors and this causes other doors to have problems.

In my car it was the driver's door actuator that was faulty however the issues was that the rear doors sometimes wouldn't unlock. The driver's door seemed to work fine. Also I will note I could hear some of the locks struggling to lock and unlock, this was a hint the voltage was too low.

You should assume it's the driver's door actuator as this is by far the most common as it gets the most use. So start your diagnosis here.

I've got an easy way for you to test the driver's door actuator that I just found out by messing around today.

The driver's door actuator gets its power from the window switch block in the door. So, pull the window switch housing up and out of the door with some plastic pry tools. Then disconnect the 3 connectors. Now try your central locking.
If you had the same problem as me what will happen now is:
1. The driver's door lock doesn't respond (because it no longer has power).
2. All the other doors and the trunk work perfectly!!.

This diagnoses the problem being the driver's door actuator.
You can replace it or try to fix the motor as Oldskewel showed us, but I warn you it's pretty bloody difficult. Also, a second hand unit will probably be faulty and won't last long.

Thank you for the reply, Siddy1200.

I will try your troubleshooting steps and report back with my findings. I'd like to believe that they aren't all failing, but it is an almost 20 year old vehicle, so I wouldn't be surprised if the motors in the actuators have failed after being used that long.

Like I said the rear doors have never unlocked for me since I purchased it. I can hear the motors in the rear doors making the attempts to unlock, but they have never been successful.

Since my front passenger lock actuator is throwing me the errors and telling me its short circuiting and behaving erratically, I'm definitely going to be replacing that one. But I will still try your troubleshooting steps to see if the rear doors will unlock after disconnecting power to the driver door actuator.

[Siddy1200]

Update.

So after fixing the driver's door lock actuator my central locking was fixed, but after a few days, I could hear the rear doors struggling! The locks were working but they sounded weak.

I took the door card off the door that sounded weak and found that the cable that connects to the lock actuator was WET!
It had rained the day before. The connector has weather seals but I'm sure some water had still managed to wick it's way in.

With a hose, I watched water come in through the small gap between the window and rubber seal, then drip down inside the door, run down the vapour barrier and out the bottom grommets. Problem is, the electrical cable rests against the vapour barrier and gets wet. Because it's wrapped in a material type of electrical tape, it absorbs and wicks water all the way to the connector.

Here are some photos (I took the photos after I dried it all with a hair drier).

I'd be interested to know if anyone else has had this problem.
My car had two faults, the driver's dla was failing and the rear passenger cable was getting wet when it rained.