What is the reason for the 03020 fault in the Volkswagen Lavida preventing it from being raised or lowered?

[VanAthena]

Lavida 03020 fault preventing raising or lowering may be caused by the combination switch ground wire coming loose, main power supply breakage, poor contact or damage to the window relay contacts, coil damage, poor contact or disconnection of the safety switch, insufficient power, etc. Relay contacts: The contacts of a relay are in a normally open or normally closed state, which can be simply understood as the points where the signal is connected or disconnected by the normally open or normally closed switch are called the relay contacts. Insufficient power: It may be caused by insufficient power and needs to be reset. Press the switch to raise the window to the top and hold the switch for more than 3 seconds, then lower the window to the bottom and hold for 3 seconds.