Rear Fresh Air Blower (V80) With Rear A/C Unit
Rear Fresh Air Blower (V80) With Rear A/C Unit
• In this vehicle, all control motors are currently identical. During the basic setting, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform with the specification, the control motors will adapt incorrectly and the door control will be wrong, refer to => [ A/C Control Motor Block Diagram ] A/C Control Motor Block Diagram.
• Using the output diagnostic test mode and basic setting functions, the activation of A/C system electrical components can be tested if necessary (for example allocation test) using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
• After installing a new control motor, check the activation via the rear A/C display control head (E265) and the function of the control motor using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
• For the rear fresh air blower to be able to be removed, the entire center console including the base support of center console - A - and insulation mat - B - installed between the base support and rear A/C unit - C - must be removed.
Removing
- Remove the driver and front passenger seat.
- Switch off the ignition.
- Remove the base support of center console - A - and insulation mat - B -.
• A/C system malfunctions in the case of interchanged control motors and/or connectors, refer to => [ A/C Control Motor Block Diagram ] A/C Control Motor Block Diagram.
• The control motors and connectors are identical. If they are installed or connected incorrectly, the corresponding doors cannot be properly adapted and/or activated.
• Clearly label control motors and connectors prior to removal to prevent incorrect installation.
- Label connector - F - (to the rear recirculation door motor (V421) ) (to rule out confusion in the event that several connectors are disconnected at the same time).
- Disconnect connector - F -.
- Detach wiring harness - E - from cover grille - A - and air duct - C -.
Do not grasp fan wheel of rear fresh air blower, force against the fan wheel or shifting the balancing weights fastened to fan wheel may cause imbalance and then problems during operation.
- Remove bolts - B -.
- Lift air duct - A - in the area of the rear fresh air blower - D - and pull backward out of air duct - C - - direction of the arrow -.
• In vehicles with a rear A/C unit, air duct - A - is engaged in the front region to coolant lines - E - and refrigerant lines - F - (release these catches for removal).
• Air duct - C - (from the front A/C unit to the rear A/C unit) can be removed even with the air duct to the rear fresh air blower - B - installed. For this purpose, remove bolts - A -, shift air duct - C - forward (to the front A/C unit), lift rear air duct - C -, and remove it - direction of the arrow -.
- Remove bolts - A -.
- By lifting tabs - C -, release the catches in the forward direction of travel on the rear fresh air blower- D - and lift the rear fresh air blower slightly.
- By lifting tabs - B -, release the left and right catches between the rear fresh air blower- D - and rear A/C unit - E -.
- Disconnect harness connector - A - at the rear fresh air blower control module (J391) - B -.
- Lift the rear fresh air blower - C - in the forward direction of travel - direction of the arrow -.
- Detach grommet - F - with lines - E - from rear A/C unit - D -.
- Remove the rear fresh air blower - C - from rear A/C unit - D -.
Installing
Installation is carried out in the reverse order while observing the following.
- Check evaporator - A - for contamination and corresponding seals - B - for damage.
- Check condensation water drains - D - (under the rear fresh air blower) and rear A/C unit - C - for contamination.
- Check the foam seal on evaporator - B - for damage and proper adhesion.
• If the rear fresh air blower and the evaporator are replaced at the same time, first install the rear fresh air blower and then the new evaporator. The foam seal on new evaporator - B - is not preformed and must first be pressed together. This is not so simple via the rear fresh air blower.
• Pressure marks on the foam seal on evaporator - B - from the rear fresh air blower are not damage. They facilitate assembly.
- Check the connection points between the rear fresh air blower - C - and rear A/C unit - D - (groove/spring connection) for damage.
• Damaged or improperly joined components can result in noises during operation of the A/C system.
- Check lines - E - at the motor of the rear fresh air blower - H -. Contacts - G - may not be bent and they may not touch.
- Insert grommet - F - with lines - E - into the mount in rear A/C unit - D -.
- Insert the v - C - in the groove/spring connection and install it against the - direction of the arrow - into the A/C unit.
• When joining the evaporator with the rear fresh air blower, force must be applied due to the foam seal at the evaporator.
- When inserting the rear fresh air blower, pull lines - E - uniformly through grommet - F - from A/C unit - D -.
- Connect harness connector - A - to the rear fresh air blower control module - B -.
- Attach tabs - C - to the catch between the rear fresh air blower- D - and the A/C unit.
- Attach tabs - B - to the left and right catches between the rear fresh air blower- D - and rear A/C unit - E -.
- Install the screws - A -.
- Check the contact surfaces between air duct - A - and rear fresh air blower - D - for damage.
• Damaged or improperly joined components can result in noises during operation of the A/C system.
- In the case of a rear A/C unit, engage the bracket of air duct - A - in coolant lines - E - and refrigerant lines - F -.
- Insert air duct - A - forward into air duct - C - and tilt down in the area of the rear fresh air blower - D - (against the - direction of the arrow -).
- Install bolts - B -.
- Connect connector - F - to the rear recirculation door motor.
- Install the removed parts in the opposite order.
- Perform the basic setting and the output diagnostic test mode of the A/C system using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
• In this vehicle, the control motors are equipped with electronics. During the basic setting, a new control motor learns its position on the A/C unit and can then be activated by the rear A/C display control head (E265) (currently all control motors are identical). Check using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
• During the basic setting, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform with the specification, the control motors will adapt incorrectly and the door control will be wrong, refer to => [ A/C Control Motor Block Diagram ] A/C Control Motor Block Diagram.
- Check the event memory of the rear A/C display control head and the Climatronic control module and erase any displayed malfunctions using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.