Alarm and locking issues

First noticed the drivers side rear door would unlock when it was very cold out.
Last night the alarm sounded by itself.
Today I noticed the alarm would not arm when locking the car.
Alarm sounded again this evening.

I connected VAG COM and I have a F222 - left rear door implausible.
opening the left rear door turns on the interior lights so it seems part of the system works.

So is there a way to further troubleshoot this?

Is it the lock module within that door?

What does ross-tech wiki say about that particular DTC?

Mostly references to replacing the module.
I need to get back out there and use VAG COM to perform some more tests when it is cold out.

Also, according to the Bentley manual I need to remove the rear door window to get the carrier out. The manual states there is not enough clearance. Anyone done this on a rear door?

I've never done the rear door but it looks similar to the front in the Bentley.
My 30 has 2 bolts to loosen to get the glass out. Real easy.
No way I could get it apart w/o removing the glass.
It was harder getting the rest out & back in for me.

Had the front drivers door module go in much the same manner. Replaced module and it's bee fine since.

Have two cars with problematic rear DLCMs (Door Lock Control Modules). After looking at how much harder these are to do than the fronts (I've done a couple fronts) I'm going to let them ride until they become unbearable. IMO one of the advantages of a 2-door.

If I am not mistaken, there are 4 switches in these door latches.

One each for door open, door closed, door locked, door unlocked.

Or maybe it is just two switches. One for open/closed, and one for locked/unlocked.

If any (either) of those switches malfunctions, it can cause the problems you are having.

Now more trouble...GRRR

I replaced the left rear latch assembly. Looks like the fault code is gone now.

The work was not too bad, slightly managed the triple square bolts, even with the correct bit.

Now I have another issue. The alarm still wouldn't arm, no sound on locking.
VAG-COM shows hood open (it is closed) It also reported the last 4 alarms were due to the hood.

It suddenly started working again today, then the alarm sounded tonight.

I disconnected the connector to the hood switch, now VAG-COM shows hood closed.

Is this the expected operation of the hood switch circuit?
(open circuit = hood closed)

Maybe check out grounds?

Are you sure it's unlocking? Or did you just not notice that it did not lock? Both mine do that left rear. I just manually lock or turn on the child lock edge of door.

dschultz said:

It suddenly started working again today, then the alarm sounded tonight.
I disconnected the connector to the hood switch, now VAG-COM shows hood closed.
Is this the expected operation of the hood switch circuit?
(open circuit = hood closed)

Click to expand...

I couldn't find much in the Bentley except the switch is part of the hood latch mech.
My diagram does not indicate which is open or closed hood.
It's possible it could be open with the hood closed.
If it is in the latch mech I wonder if sale & grime go in there and causing a short (trigger the alarm) with moisture.
Maybe run the car with the plug out a few days & see if the alarm trips.
Do you have a meter to check the switch action?
Funny part, my diagram shows pins 1 and 14 of the radio tie into the same hood switch wire going to the CCM.

Thanks for the info about the radio anti-theft switch.

Must be that German Engineering...When the computer thinks the hood switch is open it could be the radio

I had the interior apart for painting over the summer.
This morning I couldn't get the alarm to arm.
I got in the car and pushed in on the radio, it seemed to be in place.
The alarm armed. so just maybe...

I am going to keep an eye on it.

This just after fixing water leaks, sunroof drains, taking the interior apart twice...

dschultz said:

Must be that German Engineering...When the computer thinks the hood switch is open it could be the radio

Click to expand...

Of course, makes perfect sense!

dschultz said:

This morning I couldn't get the alarm to arm.
I got in the car and pushed in on the radio, it seemed to be in place.
The alarm armed. so just maybe...
I am going to keep an eye on it.

Click to expand...

Interesting.
From the diagram it looks like the wires connect mid stream somewhere, not at the radio plug, but it also did not saw exactly where.
Maybe with VAG COM hooked up bang the radio a bit to see if the set bits toggle?
If you could reach under the dash & wiggle the wires?
Might not be easy.
The shared ground is at the: 'LEFT REAR OF ENGINE COMPT' from the diagram.
Maybe a bad ground?
Running out of ideas.