How to Troubleshoot the Climate Control System (Climate Control)
Control System DTCs
How to Troubleshoot the Climate Control System
How to Check for DTCs With the HDS
1. Make sure the ignition switch is in LOCK (0).
2. Connect the HDS to the DLC (A) located under the driver's side of the dashboard.
3. Turn the ignition switch to ON (II).
4. Make sure the HDS communicates with the vehicle and the climate control unit. If it does not, go to the DLC circuit troubleshooting Testing and Inspection.
5. Select HVAC/CLIMATE CONTROL in the BODY ELECTRICAL menu.
6. Select DTCs in the HVAC/CLIMATE CONTROL menu.
7. Check for DTCs. If any DTCs are indicated, write down the DTCs, then go to the indicated DTC troubleshooting. If no DTCs are indicated, do all system scan, then refer to symptom troubleshooting.
NOTE:
* After troubleshooting, clear the DTCs with the HDS.
* For specific operations, refer to the user's manual that came with the HDS.
How to Use the Self-Diagnostic Function With the HDS
1. Make sure the ignition switch is in LOCK (0).
2. Connect the HDS to the DLC.
3. Turn the ignition switch to ON (II).
4. Make sure the HDS communicates with the vehicle and the climate control unit. If it does not, go to the DLC circuit troubleshooting Testing and Inspection.
5. Select HVAC/CLIMATE CONTROL in the BODY ELECTRICAL menu.
6. Select INSPECTION in the HVAC/CLIMATE CONTROL menu.
7. Select CLIMATE CONTROL SELF TEST in the INSPECTION menu.
8. Check for DTCs. If any DTCs are indicated, write down the DTCs, then go to the indicated DTC troubleshooting.
NOTE:
* After troubleshooting, clear the DTCs with the HDS.
* For specific operations, refer to the user's manual that came with the HDS.
How to Use the Self-Diagnostic Function Without the HDS
The climate control unit has a self-diagnostic function. To run the self-diagnostic function, do the following:
1. Turn the ignition switch to LOCK (0), and then back to ON (II).
2. Press and hold the ON/OFF button, then within 10 seconds press and release the REAR WINDOW DEFOGGER button five times. Release the ON/OFF button.
3. ALL LCD segments come on for 2 seconds, then the self-diagnostic function begins.
NOTE:
* The blower motor will run at various speeds regardless of what the panel is displaying.
* If there is any problem in the system, the system flashes 88 or alternately flashes 88. Refer to checking for DTCs.
* If there are no problems detected, the system will flashes no.
Canceling the Self-Diagnostic Function
4. Turn the ignition switch to LOCK (0) to cancel the self-diagnostic function. After completing repair work, run the self-diagnostic function again to make sure that there are no other DTCs.
How to check the past DTC's
The climate control unit can record DTCs of the past trouble. How to read the past DTC is as follows.
1. Turn the ignition switch to LOCK (0), and then back to ON (II).
2. Press and hold both the AUTO and ON/OFF buttons.
3. During press and hold both the AUTO and ON/OFF buttons, and the past trouble is indicate.
NOTE:
* If there is any problem in the system, the system flashes 88 or alternately flashes 88. Refer to checking for DTCs.
* If there are no problems detected, the system will flashes no.
Canceling the read past DTC's
4. Turn the ignition switch to LOCK (0), to cancel the read past DTC's. After completing the repair work, clear the DTCs.
How to clear the past DTC's
1. Turn the ignition switch to LOCK (0).
2. Press and hold both the AUTO and WINDSHIELD DEFROSTER buttons, then turn the ignition switch to ON (II).
3. After about 5 seconds the windshield defroster indicator starts to blink, release the buttons. The indicator will blink 5 times then stop.
4. Do the display DTC function to verify DTC's have been cleared.
Checking for DTCs
The temperature display indicates single or multiple DTCs. If no DTCs are present, the indicator remains blank.
NOTE: If temperature indicator segments 05, 07, 09, and 89 indicator are on at the some time, there may be an open in the sensor common ground wire.
Displaying Sensor Inputs at the Climate Control Unit
The climate control unit has a mode that displays the sensor inputs it receives. This mode shows you what the climate control unit is receiving from each of the sensors, one at a time, and it can help you determine if a sensor is faulty.
Checks Before Using the Sensor Input Display Mode
1. Turn the ignition switch to ON (II), and check the recirculation door function; press the RECIRCULATION button to switch from FRESH to RECIRC. The air volume and sound should change slightly.
2. Set the temperature control switch to the desired test temperature:
* "Lo" temperature setting will default to MAX COOL, VENT, and RECIRC (A/C on) or FRESH (A/C off).
* "Hi" temperature setting will default to MAX HOT, HEAT, and FRESH.
* 59 through 84 °F (15 through 29 °C) settings will use the automatic climate control logic.
3. Turn the ignition switch to LOCK (0).
Run the Sensor Input Display Mode
1. Turn the ignition switch to LOCK (0), and then back to ON (II).
2. Press and hold both the AUTO and RECIRCULATION buttons, then start the engine.
3. After the engine starts, release both buttons. The climate control unit will flash the sensor number and then the value for that sensor. Record the value displayed.
4. To advance to the next sensor, press the REAR WINDOW DEFOGGER button.
NOTE:
* The sensor values will be displayed in degrees Celsius (°C) or an alphanumeric code. Use the chart to convert the value to degrees Fahrenheit (°F).
* If the sensor value displays "Er", this indicates there is an open or short in the circuit or sensor. Check for DTCs using the HDS, or use the climate control self-diagnostic function.
* If necessary, compare the sensor input display to a known-good vehicle under the same test conditions.
* If the sensor displayed value is out of the normal range, refer to the sensor test or substitute a known-good sensor, and recheck.
