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Symptom Troubleshooting Index

WARNING: This page is about a different car, the 2008 Acura TL and 2007 Acura TL. However, it is still accessible from the selected car via links, so may be relevant.
SYMPTOM TROUBLESHOOTING CHART

Symptom Diagnostic procedure Also check for
Recirculation control doors do not change between Fresh and Recirculate Recirculation control motor circuit troubleshooting (see RECIRCULATION CONTROL MOTOR CIRCUIT TROUBLESHOOTING  )
Blower, heater controls, and A/C do not work Climate control power and ground circuit troubleshooting (see CLIMATE CONTROL POWER AND GROUND CIRCUIT TROUBLESHOOTING  )
  • HVAC DTCs (see HOW TO CHECK FOR DTCS WITH THE HDS  )
  • Blown fuse No. 30 (7.5 A) in the under-dash fuse/relay box
  • Poor ground at G503 and G601
  • Cleanliness and tightness of all connectors
Both fans do not run at low speed with the A/C on (but the A/C compressor runs with the A/C on) Radiator and A/C condenser fan low speed circuit troubleshooting (see RADIATOR AND A/C CONDENSER FAN LOW SPEED CIRCUIT TROUBLESHOOTING  )
  • HVAC DTCs (see HOW TO CHECK FOR DTCS WITH THE HDS  )
  • Blown fuse No. 9 (30 A) in the under-hood fuse/relay box, and No. 30 (7.5 A) in the under-dash fuse/relay box
  • Poor ground at G301
  • Cleanliness and tightness of all connectors
The A/C condenser fan does not run at high speed (but both fans run at low speed and the A/C compressor operates with the A/C on) A/C condenser fan high speed circuit troubleshooting (see A/C CONDENSER FAN HIGH SPEED CIRCUIT TROUBLESHOOTING  )
  • HVAC DTCs (see HOW TO CHECK FOR DTCS WITH THE HDS  )
  • Blown fuse No. 30 (7.5 A) in the under-dash fuse/relay box
  • Poor ground at G201
  • Cleanliness and tightness of all connectors
Both fans do not run at high speed with the A/C on (but both fans run at low speed and the A/C compressor operates with the A/C on) Radiator and A/C condenser fan high speed circuit troubleshooting (see RADIATOR AND A/C CONDENSER FAN HIGH SPEED CIRCUIT TROUBLESHOOTING  )
The A/C compressor clutch does not engage (but both fans run with the A/C on) A/C compressor clutch circuit troubleshooting (see A/C COMPRESSOR CLUTCH CIRCUIT TROUBLESHOOTING  )
  • HVAC DTCs (see HOW TO CHECK FOR DTCS WITH THE HDS  )
  • Blown fuse No. 12 (7.5 A) in the under-hood fuse/relay box, and No. 30 (7.5 A) in the under-dash fuse/relay box
  • Cleanliness and tightness of all connectors
A/C system does not come on (both fans and the A/C compressor do not work); heater is OK A/C pressure switch circuit troubleshooting (see A/C PRESSURE SWITCH CIRCUIT TROUBLESHOOTING  )
Blower fan runs slower than expected in cold weather ECT Troubleshooting: ECT sensor 2 circuit low voltage (see DTC P2184: ECT SENSOR 2 CIRCUIT LOW VOLTAGE ), ECT sensor 2 circuit high voltage (see DTC P2185: ECT SENSOR 2 CIRCUIT HIGH VOLTAGE )
NOTE: It is normal for the blower to run slowly until the engine coolant temperature begins to rise. If the blower continues to run slowly for an abnormal length of time, continue to troubleshoot the problem.
Both fans run at high speed all the time with the A/C on Radiator and A/C condenser fan high speed circuit troubleshooting (see RADIATOR AND A/C CONDENSER FAN HIGH SPEED CIRCUIT TROUBLESHOOTING  )
HDS does not communicate with the climate control unit or the vehicle Troubleshooting DLC circuit (see DLC CIRCUIT TROUBLESHOOTING (PART 2) )  
Insufficient heating
  1. Check the coolant level (see COOLANT CHECK ).
  2. Check the radiator cap (see RADIATOR CAP TEST ).
  3. Check the operation of the air mix control motor and door: driver's air mix control motor (see DRIVER'S AIR MIX CONTROL MOTOR TEST  ), passenger's air mix control motor (see DRIVER'S AIR MIX CONTROL MOTOR REPLACEMENT  ).
  4. Check the coolant temperature.
  5. Check the operation of the heater valve (see HEATER VALVE CABLE ADJUSTMENT  ).
  6. Check the blower motor unit for obstructions.
  7. Check for air leaks around the ducts and vents.
  8. Check the inlet hose temperature.
    • If it COLD, check for restrictions in the hose a damaged or leaking thermostat, and a damaged or leaking water pump.
    • If it 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
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