A/C relay

Fig 1: A/C Relay

Courtesy of SAAB-SCANIA OF AMERICA, INC.

Fig 2: A/C Relay Wiring

Courtesy of SAAB-SCANIA OF AMERICA, INC.

The main instrument unit is connected to the relevant engine management system's output to the A/C relay on pin 8 (K22). The engine management system grounds the output when the A/C relay is to be activated and the main instrument unit sends this information on the bus as A/C relay ON. DICE uses the information for activation of the radiator fans.