Rear demist

Fig 1: Identifying Rear Demist

Courtesy of VOLVO CARS OF NORTH AMERICA.

There are heating loops in the glass for demisting and to prevent ice from forming. The loops heat up when they are supplied with power. The power supply is via a relay on the rear relay box. The relay is controlled by the rear electronic module (REM).

Rear demist is controlled using a switch on the right-hand side of the climate control module (CCM).

The engine must be running for the demister to work. Press the button again to switch off the function. Demisting is switched off automatically after the maximum time of 12 minutes.

The relay can be diagnosed by the rear electronic module (REM). The switch can be diagnosed via the climate control module (CCM).