How to Replace the Comfort Module in a Passat B5?
4 Answers
You need to enter the security login code 40168 before calibrating each sensor, and the security code must be entered for matching each sensor. Before matching the G85 steering angle sensor, the steering angle data stream must be read within the range of ±5 degrees to proceed with the G85 matching; otherwise, the matching will fail. After the G85 data stream is within the range of ±5 degrees, exit the diagnostic tool, re-enter the system basic adjustment after successfully inputting the security login code 40168. After inputting, the dashboard will emit a beep prompt, then turn the steering wheel fully to the left and wait for three seconds, then turn it fully to the right and wait for three seconds, finally return the steering wheel to the center position, and the fault light will turn off.
Last year, I replaced the comfort module on my Passat B5 by myself. First, I prepared a new module and a T20 screwdriver. Disconnecting the negative terminal of the battery is a must, otherwise, it's easy to blow a fuse. After removing the trim panel above the footwell on the passenger side, you can see this small black box, which has four securing screws. When unplugging the connectors, be especially careful to mark the wiring harness order—I didn’t make any marks initially and ended up reinstalling it three times. After installing the new module, don’t rush to put the trim panel back on; first, reconnect the battery to test the window lift and central locking functions. The most troublesome part was the matching process—I used an OBD scanner to perform basic settings, but the remote key still needed to be reprogrammed. The whole process took over two hours, and my biggest takeaway was how fragile the interior clips are—I broke three before realizing I needed to use a specialized tool.
Last time when helping a friend replace this module, I noticed some details to pay attention to: First, confirm the module model, as the B5 has both single and double door versions. All you need are a Phillips screwdriver and a plastic pry bar. Remove the passenger side carpet to expose the metal frame, the module is located next to the wiper motor. The key point is to take photos to record the wiring sequence before unplugging the connector, as there's a purple wire that's easy to insert into the wrong slot. After installation, you must reset it with a diagnostic tool, otherwise the car locking function may fail. I recommend cleaning the drainage holes while you're at it, as water accumulation here can easily corrode the module. DIY replacement can save you three hundred in labor costs, but never pull the wiring harness forcefully—the repair shop has seen many cases of broken pins. When matching the key, just hold the lock button for ten seconds, and remember to turn off the interior lights to prevent battery drain.
Removing and installing the comfort module is actually quite simple: First, disconnect the negative battery cable—safety first. Lift the passenger side carpet to find the black control box, which is secured by four screws. Make sure not to buy the wrong module model! The B5 uses parts starting with 1J0. During installation, align the connector clips properly; you should hear a click when it's fully seated. I've noticed many people forget to reset the system, which causes the window anti-pinch function to fail. Just use a diagnostic tool to access Channel 46 and perform a basic setting. While you're at it, check the wiring harness for any signs of aging or exposed wires. If you're skilled, the whole job can be done in forty minutes. I recommend choosing a sunny day for the task—your knees won't hurt as much when kneeling in the car. Finally, don’t forget to test the sunroof synchronization function.
