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Heater Core Inspection

  1. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .)
  2. Discharge the refrigerant. (See REFRIGERANT RECOVERY .) (See REFRIGERANT CHARGING .)
  3. Drain the engine coolant. (See ENGINE COOLANT REPLACEMENT .)
  4. Remove the dashboard. (See DASHBOARD REMOVAL .) (See DASHBOARD INSTALLATION .)
  5. Remove the A/C unit. (See A/C UNIT REMOVAL/INSTALLATION .)
  6. Remove the heater core. (See A/C UNIT DISASSEMBLY/ASSEMBLY .)
  7. Inspect the heater core for damage, cracks, and water leakage.
  8. Visually inspect the fins for bending.
    • If there is any bending, use the end of a flathead screwdriver to straighten the fins.
  9. Visually inspect the heater hose for deformation.