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Symptom Troubleshooting Index

WARNING: This page is about a different car, the 2009 Honda S2000 and 2008 Honda S2000. However, it is still accessible from the selected car via links, so may be relevant.

For electrical malfunctions which are indicated by the self-diagnostic system, refer to self-diagnostic function (see GENERAL TROUBLESHOOTING INFORMATION ).

DTC Troubleshooting Index

Symptom Diagnostic procedure Also check for
Recirculation control doors do not change between Fresh and Recirculate RECIRCULATION CONTROL MOTOR CIRCUIT TROUBLESHOOTING 
  • Blown No. 20 (7.5 A) fuse in the under-dash fuse/relay box
  • Cleanliness and tightness of all connectors
Blower and heater controls do not work HEATER CONTROL POWER AND GROUND CIRCUIT TROUBLESHOOTING 
  • Blown No. 56 (40 A) fuse in the main under-hood fuse/relay box, and No. 20 (7.5 A) fuse in the under-dash fuse/relay box
  • Poor ground at No. G201, G402
  • Cleanliness and tightness of all connectors
Insufficient heating
  1. Check the coolant level (see COOLANT REPLACEMENT )
  2. Check the radiator cap (see RADIATOR CAP TEST )
  3. Check the coolant temperature
  4. Check the operation of the air mix control motor and door (see AIR MIX CONTROL MOTOR TEST )
  5. Check the operation of the heater valve (see DUST AND POLLEN FILTER REPLACEMENT )
  6. Check the blower motor for obstructions
  7. Check for air leaks around the ducts and vents
  8. Check the inlet heater hose temperature
    • If it is COLD, check for restrictions in the hose, a damaged or leaking thermostat, and a damaged or leaking water pump.
    • If it is HOT, check for restrictions in the heater core. Back flush the heater core using standard commercially available equipment, or replace the heater core.
Damaged cylinder head gasket