( TL19E00G10500000000HBAT00 )

Climate Control Symptom Troubleshooting Index

Symptom | Diagnostic procedure | Also check for
--- | --- | ---

Blower, heater controls, and A/C do not work

Climate control power and ground circuit troubleshooting

- HVAC DTCs
- Blown fuse No. 16 (7.5 A) in the driver's under-dash fuse/relay box
- Faulty blower motor relay
- Poor ground at G401:

- | There is navigation
- | Without navigation

- Cleanliness and tightness of all terminals

Voice communication does not work

Navigation communication line circuit troubleshooting

- HVAC DTCs
- Cleanliness and tightness of all terminals

HVAC display is not indicated

Audio communication line circuit troubleshooting

- HVAC DTCs
- Cleanliness and tightness of all terminals

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

- HVAC DTCs
- Blown fuse No. 3−6 (MAIN FAN MTR) (30 A) in the under-hood fuse/relay box
- Faulty radiator fan relay
- Faulty fan control relay in the relay circuit board
- Cleanliness and tightness of all terminals

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

- HVAC DTCs
- Blown fuse No. 5 (20 A) in the under-hood fuse/relay box
- Faulty A/C condenser fan relay in the relay circuit board
- Cleanliness and tightness of all terminals

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)

A/C pressure sensor troubleshooting: A/C pressure sensor circuit low voltage, R20A3 engine model, K24Z3 engine model, A/C pressure sensor circuit high voltage, R20A3 engine model, K24Z3 engine model

- Powertrain DTCs, R20A3 engine model, K24Z3 engine model
- Cleanliness and tightness of all terminals

The A/C compressor clutch does not engage (but both fans run with the A/C on)

A/C compressor clutch circuit troubleshooting

- HVAC DTCs
- Blown fuse No. 20 (7.5 A) in the under-hood fuse/relay box
- Faulty A/C compressor clutch relay
- Blower motor operation
- Cleanliness and tightness of all terminals

A/C system does not come on (both fans and the A/C compressor do not work); heater is OK

A/C signal circuit troubleshooting A/C pressure sensor troubleshooting: A/C pressure sensor circuit low voltage, R20A3 engine model, K24Z3 engine model, A/C pressure sensor circuit high voltage, R20A3 engine model, K24Z3 engine model

- HVAC DTCs
- Powertrain DTCs, R20A3 engine model, K24Z3 engine model
- Cleanliness and tightness of all terminals

Blower fan runs slower than expected in cold weather

ECT troubleshooting: ECT sensor 2 circuit low voltage, R20A3 engine model, K24Z3 engine model, high voltage, R20A3 engine model, K24Z3 engine model
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.

- Powertrain DTCs, R20A3 engine model, K24Z3 engine model
- Faulty blower motor operation

HDS does not communicate with the climate control unit or the vehicle | Troubleshoot the DLC circuit, R20A3 engine model, K24Z3 engine model |

Insufficient heating

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Check the coolant level, R20A3 engine model, K24Z3 engine model
Check the radiator cap, R20A3 engine model, K24Z3 engine model
Check the operation of the air mix control motor and door
Check the coolant temperature
Check the blower motor unit for obstructions
Check for air leaks around the ducts and vents
Check the inlet 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