Heater And A/C Unit, Removing And Installing: Installing

Install in the reverse order of removal while noting 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-.

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-- 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-, ttach connections -C- (positive) and -B-.Refer to Auxiliary Heater Control Module -J604- (WITH Auxiliary Heater Heating Element -Z35-) REMOVING AND INSTALLING .

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-- Insert the corresponding fuse. Refer to 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.

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-- Evacuate and charge the refrigerant circuit. Refer to Refrigerant Circuit or Working with A/C Service Station .

-- Switch the ignition on.

Vehicles with High-Voltage System

-- Vehicles with Heat Pump Function, Initiate the basic setting of the A/C system through the Thermal Management Control Module -J1024- and activate the power-controlled valves using the routine 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 FOR REMOVING AND INSTALLING ADJUSTMENT MOTORS .

-- Before starting the A/C system, fill and drain the engine coolant circuit. Refer to BLEED COOLING SYSTEM - 2.0 or COOLANT, ADDING AND BLEEDING COOLING SYSTEM, VEHICLE WITH HIGH-VOLTAGE SYSTEM, HIGH-VOLTAGE SYSTEM COOLANT CIRCUIT - 3.0 .

-- Operate the A/C system after charging the refrigerant circuit. Refer to A/C SYSTEM, STARTING AFTER CHARGING REFRIGERANT CIRCUIT .