Components Outside Passenger Compartment

Components Outside Passenger Compartment






1 Forced Air Extractor

• A forced air extraction vent is installed at left and right under rear bumper.

• Sealing doors on air extraction vent must be able to move freely and close automatically.

• In order for the passenger compartment ventilation to function properly, the air ducts that run through the luggage compartment trim must be unobstructed.

• Checking, refer to => [ Passenger Compartment Forced Air Extraction, Checking ] Testing and Inspection.

2 Intake Grille For Fresh Air Intake

• Check for proper seating, prevents foreign objects (e.g. leaves) entering intake housing of heater unit.

• Check the bonded seal for damage and proper seating. This seal prevents water from flowing through beneath the intake grille into heater intake housing.

• Removing and installing, refer to=> [ Fresh Air Intake Cover ] Fresh Air Intake Cover.

3 Fresh Air Intake Cover

• Check the bonded seal for damage and proper seating. This seal prevents water between the windshield lower frame and the cover from getting into the heater air intake shroud.

• Removing and installing, refer to=> [ Fresh Air Intake Cover ] Fresh Air Intake Cover and

4 Coolant Fan (V7) and Coolant Fan 2 (V177)

• Different versions of the Coolant Fan and Coolant Fan 2 are installed depending on vehicle equipment. Refer to Electronic Parts Catalog (ETKA).

• In standard vehicle operation, the radiator fan is not activated by the Climatronic control module (J255). It will be displayed in the heater control head measured values block that the fan is not activated. Refer to Vehicle diagnosis, testing and information system (VAS5051B) in the "Guided Fault Finding" function.

• The request to switch on the Coolant Fan (V7) is only transmitted by the Climatronic control module in "Output Diagnostic Test Mode (DTM)" via the databus system to the engine control module (ECM). Then, with the engine running, the ECM activates the fan ( Coolant Fan (V7) and Coolant Fan 2 (V177) ) directly or via the Coolant Fan Control Control Module (J293). Check using Vehicle diagnosis, testing and information system (VAS5051B) in the "Guided Fault Finding" function and => Engine Mechanical 19 Description.

• With engine running, the respective engine control modules switches, for example, the Coolant Fan and Coolant Fan 2 (directly via the Coolant Fan Control Control Module) continuously to the desired output (depending on engine type). Check using Vehicle diagnosis, testing and information system (VAS5051B) in the "Guided Fault Finding" function and.

5 Outside Air Temperature Sensor (G17)

• The measured value of the Outside Air Temperature Sensor is not used by the Climatronic control module (J255) for controlling the heater. However, the measured value is used to calculate the permitted switch-on time for the Heated Rear Window (Z1).

• Measured value of Outside Air Temperature Sensor is evaluated by Instrument Cluster Control Module (J285) and transmitted via Comfort CAN-Bus system to the Climatronic control module (J255). Check using Vehicle diagnosis, testing and information system (VAS5051B) in the "Guided Fault Finding" function.

Removing and Installing

- Remove the bumper cover.

- Disconnect connector on temperature sensor and unclip from mount in air duct

6 Coolant Hose Connections To Heater Core

• Coolant hoses from connections to heater core, detaching and attaching, refer to=> [ Heater Core ] Service and Repair.

7 Plenum Chamber Water Drains

• A water drain is installed at left and right in plenum chamber.

• Grommet, removing and installing, checking and cleaning, refer to => [ Plenum Chamber Water Drain, Checking and Cleaning ] Service and Repair.

8 Heated Rear Window (Z1)

• The command to heat the rear window is sent by the Climatronic control module (J255) via the Comfort databus system. The vehicle electrical system control module (J519) controls the rear window defogger. Refer to Vehicle diagnosis, testing and information system (VAS5051B) in the "Guided Fault Finding" function and.

• Notes on function of heated rear window, refer to => [ Rear Window Defogger, Checking ] Rear Window Defogger, Checking.