Heater Core, Removing And Installing: Installing
Install in reverse order of removal and note the following:
-- Replace the seals after removing.
-- With the heater core removed, check the heater shaft for debris.
-- If necessary, remove any dirt or coolant residue.
-- Vehicles with a TDI engine: check the heating element shaft for debris when the auxiliary heater heating element is removed and clean if necessary.
-- If equipped, check the foam seals -2- attached to the heater core -1- for damage and replace if necessary.
If not bonded correctly, the foam seal may curl up during insertion.
Cold air may flow past heater core if the foam seal is damaged or not installed correctly.
-- Check the heater core connection -3- and the connection -2- for the coolant pipes for damage or debris.
-- Clean and smooth the sealing surface for the gasket.
-- Coat a new seal -4- with coolant (or lightly with silicone grease) and attach it to the coolant pipe -1-.
-- Carefully slide the heater core all the way into the heater and A/C unit until stop.
-- Slide the coolant pipes into the heater core until stop.
There is a risk of heater core malfunctions due to faulty seals and leaks.
Never pinch the seals.
Never tilt the coolant pipes.
Slide the coolant pipes on all the way.
-- Position a new clip -5- or screw-type clamp -2- on the coolant pipe/heater core connection.
-- Tighten the bolt -3-. Refer to OVERVIEW - HEATER AND A/C UNIT .
-- Check the clamp and screw-type clamp for proper seating on the heater core and the coolant pipe connections. They must not be touching the air distribution housing or any other components.
-- Fill with coolant. Refer to [For engine(s) DGXA, DJXA] Cooling System/Coolant / [For engine(s) DKFA] Cooling System/Coolant .
-- Check the DTC memory and erase any displayed entries using the Vehicle Diagnostic Tester in the Guided Fault Finding function.
-- Check the heating and A/C system function.