How to Troubleshoot the Air Conditioning in a VW Passatby Contributor
It seems air conditioning problems are unfortunately fairly common in Volkswagen Passats. Many owners find themselves in the repair shops of the dealers during hot summer months trying to get the problem fixed. Save some time and money by trying to diagnose the problem yourself before making a trip to the dealer.
Listen for the blower fan to make sure it is working. With the engine on, turn on the air and adjust the pressure. The normal accompanying sound indicates the blower fan is working properly.
Remove the blower fan in a VW Passat by unscrewing the footwell panel on the passenger side, removing it, unscrewing the blower fan and then unplugging the electricity to it. There is only one small cable running to the blower fan which transmits the electricity.
Look at the graphics display on the dashboard. If it is blank, or if the air flow controls do not work properly, the problem is in the control panel.
Remove the trim panels on the passenger side, unscrew the four panel screws, and detach the cables from the controls. Unplug the electrical connector and remove the control panel.
Check the fuses next if the controls and graphic displays are fine. Get to the fuse box in a VW Passat by opening the driver's door and prying off the side panel directly next to the steering wheel carefully.
Replace the fuse with one that is the same amount of voltage to avoid damaging the entire electrical system. The fuse will be red.
Check the cables that circulate the air next. The control panel will need to be removed first. Find the cable that extends from the heating and air conditioning unit. It will be small and black. Inspect it along with its connections to make sure there are no leaks.