You really are a vw driver's advocate to stay involved with this topic for so long and by continuing to add new observations and advice.
I want to list the symptoms I've been experiencing for sometime on my '00 golf and confirm which ones we think are more than likely to be from the cracked soldering or a mechanically issue with that 4th micro-switch. Then there's a couple of other symptoms I want to run past you and anyone else that has experienced this.
Alarm auto-arms after the front driver or passenger door is open 20secs or so, but does not if either rear door is opened as well or by themselves. Interestingly; when it faultily rearms this way the alarm led also does not light.
-typically intermittent, sometimes it will work correctly and not auto-arm if either front door is opened.
Red /white lower lights do not light on either front door at anytime.
Opening the rear doors lights the dome but opening either front door does not.
The pin on the front driver side does not go down while alarm is arming unless I press unlock twice and then lock/ arm quickly on the remote. It also does not go down very often while it is faultily auto-arming.
-although occasionally it goes down like it should.
Occasionally the windows do not go up with the key from the outside.
^^^^^^ I think these first 5 we've seen so often that its pretty certain it would be cleared up by repairing or replacing the locking module but what about these?;
The pin on the front passenger side does not go down at all unless you push it, it doesn't goes up unless you pull the handle from the inside. Does not change, never works period.
-I did see a few other people talk about this but from reading the thread I couldn't completely confirm that this fix worked for that symptom.
Nothing works on the front passenger door actually, no lights, no mirror, no pin, no window.
-not intermittent, never works. I haven't seen anyone else mention that they have experienced this.
I'm suspecting that I've got an issue with power not getting to that passenger door and this is causing an otherwise non-faulty module not to work.
Each thing that stopped working happened 1 at a time though, it didn't go down all at once, the first thing was the pin not going down.
Any suggestions on how to check for power to the door -all the fuses seem fine etc.
Then finally; what is the locking module we are talking about here labeled in the Bentley wiring diagrams? F221 (driver) F222 (pass) locking unit for central locking? or J386 (driver) J387 (pass) door control module? or are one of these part of the other?
Thanks for any further input you can give to this topic!