Heater And A/C Unit, Removing And Installing: Installing
Install in reverse order of removal and note the following:
- Check all seals and grommets on the heater and A/C unit for damage before installing and replace any damaged parts.
-- Coat the grommet -B and C- with grease and install it in the plenum chamber rear panel -A-.
-- Insert the support ring -D- in the grommet.
-- Check the position of the coolant and refrigerant lines in both grommets in the plenum chamber rear panel, and if necessary, align the heater and A/C unit so that the lines are not tensioned in the grommets.
-- In vehicles with an Auxiliary Heater Control Module -J604- with an Auxiliary Heater Heating Element -Z35-, attach connections -C- (positive) and -B-. Refer to Auxiliary Heater Control Module .
-- Insert the corresponding fuse. Refer to the appropriate Wiring Diagram.
-- Remove the refrigerant line from the front expansion valve. Refer to FRONT EXPANSION VALVE, REMOVING AND INSTALLING .
-- Install the coolant hoses -A- and -B- on the coolant pipes to the heat exchanger in the front heater and A/C unit.
-- Evacuate and charge the refrigerant circuit. Refer to Refrigerant Circuit or Working with A/C Service Station (1 Of 2) / Working with A/C Service Station (2 Of 2) .
-- Switch the ignition on.
Vehicles with high-voltage system (Audi Q7 e-tron)
-- Initiate the basic setting of the A/C system through the Thermal Management Control Module -J1024- and activate the power-controlled valves using one of the routines stored there. "Charge/flush the refrigerant circuit stop routine" using the Vehicle Diagnostic Tester.
-- Operate the Electrical A/C Compressor -V470- via the "compressor cut-in" function. Use the Vehicle Diagnostic Tester in the "Guided Fault Finding" function for the A/C system.
Continuation for All Vehicles
-- Perform a basic setting for the A/C system. Refer to GENERAL INFORMATION AND PROCEDURES - ACTUATORS, REMOVING AND INSTALLING .
-- Before starting the A/C system, fill and drain the coolant circuit. Refer to COOLANT, DRAINING AND FILLING .
-- Start the A/C system after charging the refrigerant circuit. Refer to A/C SYSTEM, STARTING AFTER CHARGING REFRIGERANT CIRCUIT .