Symptom Troubleshooting Index

SYMPTOM TROUBLESHOOTING INDEX

Symptom	Diagnostic procedure	Also check for
All the control motors do not run	Probable cause: The control motor circuit malfunction. Do the control motor power supply circuit troubleshooting (see HVAC CONTROL MOTOR POWER SUPPLY CIRCUIT TROUBLESHOOTING )	Climate control DTCs (see HOW TO CHECK FOR DTCS WITH THE HDS ) Blown fuse No. 9 (7.5 A) in the passenger's under-dash fuse/relay box Poor or loose connections at the terminals
The aspirator fan does not run	Probable cause: The aspirator fan circuit malfunction. Do the aspirator fan circuit troubleshooting (see ASPIRATOR FAN CIRCUIT TROUBLESHOOTING )	Climate control DTCs (see HOW TO CHECK FOR DTCS WITH THE HDS ) Blown fuse No. 30 (7.5 A) in the driver's under-dash fuse/relay box Poor ground at G501 (see DASHBOARD WIRE HARNESS (LEFT BRANCH) ) Poor or loose connections at the terminals
The blower and heater controls and the A/C system do not work	Probable cause: Climate control unit malfunction. Do the climate control power and ground circuit troubleshooting (see CLIMATE CONTROL POWER AND GROUND CIRCUIT TROUBLESHOOTING )	Climate control DTCs (see HOW TO CHECK FOR DTCS WITH THE HDS ) Blown fuse No. 30 (7.5 A) in the driver's under-dash fuse/relay box Poor ground at G503 (see DASHBOARD WIRE HARNESS (CENTER BRANCH) ) Poor or loose connections at the terminals
The A/C condenser fan and/or the radiator fan do not run with the A/C on	Do the radiator and A/C condenser fans common circuit troubleshooting (see RADIATOR FAN AND A/C CONDENSER FAN CIRCUIT TROUBLESHOOTING )	Powertrain DTCs (see GENERAL TROUBLESHOOTING INFORMATION ) Blown fuses No. 23 (7.5 A) in the driver's under-dash fuse/relay box and No. 34 (50 A) in the battery terminal fuse box Faulty radiator fan control (RFC) unit relay Faulty radiator fan control (RFC) unit Poor ground at G301 (see ENGINE COMPARTMENT WIRE HARNESS (LEFT BRANCH) ) Poor or loose connections at the terminals
The A/C condenser fan does not run at all (but the radiator fan and the A/C compressor run with the A/Con)	Do the A/C condenser fan circuit troubleshooting: open (see A/C CONDENSER FAN CIRCUIT TROUBLESHOOTING (OPEN) ), short (see A/C CONDENSER FAN CIRCUIT TROUBLESHOOTING (SHORT) )	Powertrain DTCs (see GENERAL TROUBLESHOOTING INFORMATION ) Faulty A/C condenser fan motor Faulty radiator fan control (RFC) unit Poor or loose connections at the terminals
The radiator fan does not run at all (but the A/C condenser fan and the A/C compressor run with the A/Con)	Do the radiator fan circuit troubleshooting: open (see RADIATOR FAN AND A/C CONDENSER FAN CIRCUIT TROUBLESHOOTING ), short (see A/C CONDENSER FAN CIRCUIT TROUBLESHOOTING (OPEN) )	Powertrain DTCs (see GENERAL TROUBLESHOOTING INFORMATION ) Faulty radiator fan motor Faulty radiator fan control (RFC) unit Poor or loose connections at the terminals
The blower fan runs slower than expected in cold weather (when in AUTO mode) NOTE: It is normal for the blower fan to run slowly until the coolant temperature rises when in AUTO mode	Probable cause: Engine coolant temperature (ECT) circuit malfunction. Troubleshoot ECT 2 circuit performance problem (see DTC P2183: ECT SENSOR 2 CIRCUIT RANGE/PERFORMANCE PROBLEM )	Climate control DTCs (see HOW TO CHECK FOR DTCS WITH THE HDS ) Powertrain DTCs (see GENERAL TROUBLESHOOTING INFORMATION ) Manual blower motor operation
The A/C compressor clutch cycles rapidly on and off	Probable cause: A/C system is very low on refrigerant, indicating a possible leak. Do the refrigerant leak check (see REFRIGERANT LEAK CHECK ) and repair any leaks. Replace the receiver/dryer (see A/C COMPRESSOR REPLACEMENT ), then recharge the system to specifications (see SYSTEM CHARGING )	Climate control DTCs (see HOW TO CHECK FOR DTCS WITH THE HDS ) If there is no leak and the refrigerant level is normal, do the A/C compressor clutch circuit troubleshooting (see A/C COMPRESSOR CLUTCH CIRCUIT TROUBLESHOOTING ), and look for an intermittent problem. Low idle ECT
The A/C compressor clutch does not disengage when the A/C switch is off	Probable cause: The A/C compressor clutch circuit is on (energized) continuously, shorted to ground, stuck A/C compressor clutch relay, or the A/C compressor clutch is mechanically jammed Do the A/C compressor clutch circuit troubleshooting (see A/C COMPRESSOR CLUTCH CIRCUIT TROUBLESHOOTING ), and repair any circuit problems If the A/C compressor clutch circuit is OK, then do the A/C compressor clutch check (see A/C COMPRESSOR CLUTCH CHECK ), and repair any problems with the A/C compressor clutch	The A/C compressor relief valve. If it has vented refrigerant to the atmosphere, correct the problem with the A/C compressor clutch or clutch circuit, then replace the relief valve (see A/C COMPRESSOR RELIEF VALVE REPLACEMENT ).
The A/C compressor relief valve has vented refrigerant NOTE: This indicates the A/C system pressure was very high	Probable cause: A high-side restriction, the A/C condenser/radiator fans are inoperative, or the A/C compressor clutch is not disengaging If the fans and A/C compressor clutch operate normally, recover refrigerant (see REFRIGERANT RECOVERY ), and check for restrictions If the A/C compressor clutch will not disengage, troubleshoot the A/C compressor clutch circuit (see A/C COMPRESSOR CLUTCH CIRCUIT TROUBLESHOOTING ), and check for mechanical problems (see A/C COMPRESSOR CLUTCH CHECK ) If the fans are inoperative, troubleshoot the fan circuits (see A/C CONDENSER FAN CIRCUIT TROUBLESHOOTING (OPEN) )	Powertrain DTCs (see GENERAL TROUBLESHOOTING INFORMATION )
HDS does not communicate with the climate control unit or the vehicle	Troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING )
Insufficient heating	Check the coolant level (see COOLANT CHECK ) Check the radiator cap (see RADIATOR CAP TEST ) Check the coolant temperature during normal operation Check the heater core inlet hose temperature: If it is COLD, check the heater valve and the cable for proper operation (see HEATER VALVE CABLE ADJUSTMENT ) restrictions in the hose, a damaged or leaking thermostat, or a damaged or leaking water pump, an operation of the heater valve If it is HOT, check the heater valve and the cable for proper operation (see HEATER VALVE CABLE ADJUSTMENT ). Back flush or replace the heater core Check the operation of the air mix doors: Driver's (see DRIVER'S AIR MIX CONTROL MOTOR TEST ) Passenger's (see PASSENGER'S AIR MIX CONTROL MOTOR TEST )	Climate control DTCs (see HOW TO CHECK FOR DTCS WITH THE HDS ) Damaged cylinder head gasket