Operation CHARM: Car repair manuals for everyone.

Heater Core: Service and Repair

Heater Core

1. Disconnect battery ground cable.
2. Remove radiator drain plug and allow coolant to drain.
3. Loosen heater hose clamps, then remove inlet and outlet hoses from the heater unit.
4. Separate left and right defroster ducts from nozzles and remove ducts from the heater unit.
5. Disconnect blower motor and fan switch electrical connectors.
6. Disconnect heater unit air mix and mode cables.
7. Remove heater unit to instrument panel attaching bolt.
8. Open glove compartment then, while pulling stopper clips inward, lower the glove compartment.
9. Disconnect inside-outside air control cable at blower assembly.
10. Remove instrument panel as follows:
a. Remove steering wheel as outlined under Steering Wheel.
b. Remove defroster duct.
c. Disconnect heater control cable from inside-outside air selector rod at heater unit.
d. Disconnect speedometer cable.
e. Disconnect electrical harness connector.
f. Remove instrument panel attaching bolt covers, the attaching bolts, then the instrument panel.
11. Remove blower assembly and heater unit attaching bolts.
12. Carefully remove heater unit.
13. Remove heater core cushion.
14. Loosen and remove heater core holder.
15. Remove heater core from heater unit.
16. Reverse procedure to install.