HEATER AND A/C UNIT, REMOVING AND INSTALLING, "High" A/C SYSTEM, PR NUMBER 9AH/ 9AQ: Removing
- For all the following work, close the open lines and connections with clean plugs from the Engine Bung Set :VAS6122 .
Vehicles with high-voltage system (Audi Q7 e-tron)
-- Switch off (deactivate) the "parking air conditioner". Refer to Owner's Manual.
-- Initiate the A/C system basic setting through the Thermal Management Control Module -J1024- and open the power-activated valves through the stored routine "Extract, evacuate and fill the refrigerant circuit" using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
Continuation for All Vehicles
-- Switch off the ignition.
-- Discharge 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) .
The cooling system is under pressure when the engine is warm. There is a risk of scalding from hot steam and coolant.
Scalding the skin and other parts of the body is possible.
- Wear safety gloves.
- Wear protective eyewear.
- Reduce the pressure by covering the coolant expansion tank cap with a cloth and carefully opening it.
-- Carefully open the coolant expansion tank cap -A- (do not completely remove).
- There are different versions of the coolant expansion tank and with different allocations in the engine compartment. Refer to COOLANT, DRAINING AND FILLING .
-- Vehicles with 6-cylinder gasoline engine: remove the left front muffler. Refer to FRONT MUFFLER, REMOVING AND INSTALLING .
-- Place the Coolant Collecting System :VAS5014 or Shop Crane - Drip Tray :VAS6208 underneath.
-- Label the layout of the coolant hoses -C, D- at the connections to the heater core.
-- Clamp off the coolant hoses using the Hose Clamps - Up To 25mm :3094 .
-- Remove the coolant hoses by loosening the hose clamps -A, B-.
-- Remove the base support -A- of center console and insulation -B-. Refer to CENTER CONSOLE BRACKET, REMOVING AND INSTALLING .
-- Clearly label the line routing to the four temperature sensors -A- through -D- on the air ducts.
Complaints on the regulation of the A/C system due to an incorrectly addressed temperature sensor or adjustment motors.
- Prior to disconnecting connectors or removing electrical components, clearly label them in order to rule out confusion.
-- Remove the temperature Sensor -A through D- from the air ducts and secure together with the corresponding wire on the rear heater and A/C unit, so that interfere with removal of the heater and A/C unit -E- and are not damaged. Refer to LEFT/RIGHT REAR UPPER BODY VENT TEMPERATURE SENSOR -G635- / -G636-, REMOVING AND INSTALLING and LEFT/RIGHT REAR FOOTWELL VENT TEMPERATURE SENSOR -G637- / -G638-, REMOVING AND INSTALLING .
-- Remove the nut -A- from the connection location of the refrigerant lines.
TIP
- If the operating lever -B- is awkwardly positioned so that the nut -A- is not accessible, remove the rear recirculation door motor. Refer to Rear Recirculation Door Motor -V421-, REMOVING AND INSTALLING .
-- Loosen the heater and A/C unit -C- from the retaining points -B- and the air duct -A-.
-- Remove the refrigerant line connection -H- on the connection point to the refrigerant lines -F-.
-- Place absorbent paper around the coolant lines -E-.
-- Remove the coolant lines -E- from the heat exchanger from the grommets in the center tunnel.
-- Remove the heater and A/C unit.
-- Cover the air ducts in the rear passenger compartment so that they are not compressed or damaged during further work steps.