Auxiliary Heater Control Unit, Component Description - GF83.70-S-4030TRA

Model 447.7 

With Code HZ1 (Auxiliary heater (warm air)) 

With Code ZH6 (Marco Polo ACTIVITY) 

Model 447.8 

With Code HZ1 (Auxiliary heater (warm air)) 

With Code ZK7 (Equipment line MARCO POLO) 

View of Model 447.8 from left 

Location 

The warm air stationary heater control unit (WLSTH) is located on the underfloor.

Task 

The warm air stationary heater control unit (WLSTH) controls the auxiliary heater.

Input signals 

• Central operating unit (COU [ZBE]) control unit (N10/16) (with code ZK7 (Marco Polo equipment line)), via body manufacturer CAN (CAN MPM)
  • Blower, wide open throttle request
  • Blower, partial load request
  • Heater ON, request
  • Heater OFF, request
• Temperature sensor for vehicle interior, direct signal
• Warm air stationary heater radio remote control transmitter (A8/3), via air stationary heater radio remote control receiver (A49/6)

Output signals 

• Warm air stationary heater (WLSTH) control unit diagnosis
• Central operating unit (COU [ZBE]) control unit (with code ZK7 (Marco Polo equipment line)), via body manufacturer CAN
  • Blower, wide open throttle request
  • Blower, partial load request
  • Heater ON, request
  • Heater OFF, request

Evaluation of input factors 

The input factors that have been read in are evaluated by the integrated microprocessor and the affected components are then actuated.