Heater Core: Service and Repair

Heater Unit/Core Replacement

SRS components are located in this area. Review the SRS components locations, precautions, and procedures in the SRS section before performing repairs or service.

1. Make sure you have the anti-theft code for the radio, then write down the frequencies for the radio's preset buttons.
2. Disconnect the negative cable from the battery.




3. From under the hood, open the cable clamp (A), then disconnect the heater valve cable (B) from the heater valve arm (C). Turn the heater valve arm to the fully opened position as shown.
4. When the engine is cool, drain the engine coolant from the radiator.




5. Remove the heater valve mounting nut. Slide the hose clamps (A) back, then disconnect the inlet (B) and outlet (C) heater hoses from the heater unit. Engine coolant will run out when the hoses are disconnected; drain it into a clean drip pan. Be sure not to let coolant spill on electrical parts or painted surfaces. If any coolant spills, rinse it off immediately.




6. Remove the mounting nut from the heater unit. Take care not to damage or bend the fuel lines, the brake lines, etc.
7. Remove the dashboard.
8. Remove the heater duct or evaporator.




9. Remove the mounting bolts and the heater unit.




10. Remove the self-tapping screws and the bracket (A), then carefully pull out the heater core (B) so you don't bend the inlet and outlet pipes.
11. Install the heater core in the reverse order of removal.
12. Install the heater unit in the reverse order of removal, and note these items:
- Do not interchange the inlet and outlet heater hoses, and install the hose clamps securely.
- Refill the cooling system with engine coolant.
- Adjust the heater valve cable.
- Make sure that there is no coolant leakage.
- Make sure that there is no air leakage.
- Enter the anti-theft code for the radio, then enter the customer's radio station presets.