GF83.70-D-4064H PTC Heater Booster Control Unit, Component Description

GF83.70-D-4064H PTC Heater Booster Control Unit, Component Description

- with CODE (HH2) Electric warm air auxiliary heater







1 PTC heater booster
2 Heater or A/C housing
N33/4 Electric PTC heater booster

Location
The electric PTC heater booster is located at the PTC heater booster, which in turn is located in the heater housing or air conditioner housing in front of the front heater heat exchanger.

Task
On vehicles with the Heater variant, except code (HH9) Regulated air conditioning (Tempmatic), the electric PTC heater booster regulates the PTC heater booster as a function of the coolant temperature and of the outside temperature.
On vehicles with the Tempmatic (TM) variant, with code (HH9) Regulated air conditioning (Tempmatic), the electric PTC heater booster regulates the PTC heater booster as a function of the temperature set via the temperature selection switch (S98s14) integrated in the KLA control and operating unit (S98), of the coolant temperature and of the outside temperature.

The electric PTC heater booster is connected to the Controller Area Network bus class B (interior) (CAN-B) and uses it to communicated with the following control units:
- With the instrument cluster (A1)
- The electric PTC heater booster receives for instance "T_AUSSEN_K (instrument cluster filtered outside temperature)"

- With the CDI control unit (N3/20), with engine OM642, or with the CDI control unit (N3/21), with engine OM646, via the EIS control unit (N73)
- With the SAM control unit (N10)
- The electric PTC heater booster receives for instance "T_MOT (engine coolant temperature)"
- The electric PTC heater booster receives for instance "KL_61 EIN ("circuit 61 ON")"

- With the KLA control and operating unit
- The electric PTC heater booster receives for instance "PTC_STUFE (specified stage for PTC heater booster)"
- The electric PTC heater booster sends for instance "PTC_LEISTUNG (PTC heater booster output)"