Climate Control Symptom Troubleshooting

Symptom Diagnostic procedure Also check for 
Recirculation control doors do not change between Fresh and Recirculate Recirculation control motor circuit troubleshooting 
  • Blown fuse No. 14 (10 A) in the under-dash fuse/relay box
  • Cleanliness and tightness of all connectors
 
Blower, heater controls, and A/C do not work Heater control power and ground circuit troubleshooting 
  • Blown fuse No. 14 (10 A) in the under-dash fuse/relay box
  • Poor ground at G501
  • 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 
  • Blown fuse No. 10 (30 A) in the under-hood fuse/relay box, and No. 14 (10 A) in the under-dash fuse/relay box
  • Poor ground at G201
  • 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 
  • Blown fuse No. 14 (10 A) in the under-dash fuse/relay box
  • Poor ground at G301 (LHD type) or G201 (RHD type)
  • Cleanliness and tightness of all connectors
 
The A/C compressor clutch does not engage (but both fans run with the A/C on) A/C compressor clutch circuit troubleshooting 
  • Blown fuse No. 29 (10 A) in the under-hood fuse/relay box, and No. 14 (10 A) in the under-dash fuse/relay box
  • Cleanliness and tightness of all connectors
 
Heating normally doesn't work Magnet valve circuit troubleshooting 
  • Blown fuse No. 14 (10 A) in the under-dash fuse/relay box
  • Cleanliness and tightness of all connectors
 
Blower fan runs slower than expected in cold weather ECT sensor circuit troubleshooting
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. 
  • Cleanliness and tightness of all connectors
 
Aspirator fan does not run Aspirator fan circuit troubleshooting 
  • Blown fuse No. 14 (10 A) in the under-dash fuse/relay box
  • Cleanliness and tightness of all connectors
 
A/C indicator blinks (A/C indicator does not blink during the fan switch OFF and in the self-diagnostic mode). During the engine cool, warm air does not come out Running the self-diagnosis function