Passat: Central Locking Problem - Help!

Translated on 12-10-2026, 9:09.

Hello everyone,

I'm having a problem with a Passat 3B, manufactured in 1998.

He has the comfort control unit with the part number 1J0 959 799 J.

Some time ago, the central locking system for the rear doors stopped working simultaneously on both sides. Additionally, the remote controls stopped functioning.

After that, I reprogrammed the keys in the KSG and read the error memory.

The following errors are stored:

00930 Rear left central locking unit - F222 - no connection.
00931 Rear right central locking unit - F223 - no connection.

The door control units are recognized, and the window lifters are also working. I once removed a lock as a test and measured it. Everything was fine. I also can't imagine that both sides would fail at the same time. When I look at the measurement blocks and manually unlock/lock the doors, the control unit also recognizes this.

The encoding is also fine.

The bus is not reporting any errors either.

I've also checked the connectors on the KSG. Everything looks good.

Does anyone have any idea where the error might be?

Should the KSG be defective?

I'm really at a loss.

Does anyone have any experience with this?

Thank you.

Translated on 12-10-2026, 9:11.

Hello.
Take a look at the wiring harness on the driver's side, inside the door opening, approximately in the middle of the door cutout. There are cable connections within the wiring harness that tend to corrode. In your case, you should be looking for 4 or 5 blue/red wires that are connected together, if I remember correctly. Re-solder them and that should fix it.
Best regards,

Translated on 12-10-2026, 9:12.

Hello again,

"On Saturday, I'll be working on the car again. I'm going to test all the cables, and I've also acquired a test control unit."

Could someone please send me the wiring diagrams for the Passat 3B, model year 1998? I'm particularly interested in the diagrams for the comfort system.

Best regards,
Joachim.

Translated on 12-10-2026, 9:14.

Thanks for the tip, that was exactly the problem. The connections had contact resistance due to corrosion... It's shocking to see such shoddy workmanship on a branded product... I would be ashamed.

Unfortunately, soldering was no longer possible because the copper was too corroded. I had even cut some of the cables back by as much as 30cm, and they were still corroded and damp inside. The only option was to use crimping. Hopefully, this will last for a while.

Best regards,
Yogi.