Initial Inspection and Diagnostic Overview

How to Troubleshoot the Climate Control System

How to Check for DTCs with the HDS

- There are three methods used to check for DTCs. The recommended method is to use the Honda Diagnostic System (HDS) with the appropriate software, plugged into the data link connector (DLC).

- The second method is to run the self-diagnostic function built into the climate control unit.

- The third method is to use B-CAN system diagnosis test mode A Troubleshooting - B-CAN System Diagnosis Test Mode A.

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, 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

NOTE: This method is only available if the HDS can communication with the HVAC control unit. If there is a communication problem with the HDS, go to B-CAN system diagnosis test mode A Troubleshooting - B-CAN System Diagnosis Test Mode A.

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 ON (II).

2. Press and hold the OFF button.

3. While holding the OFF button, press the rear window defogger/mirror defogger button five times within 10 seconds. Release the buttons and the self-diagnostic function will begin.

NOTE:

- It may take up to 20 seconds for the self-diagnostic to begin.
- The blower motor can be run at various speeds regardless of what the panel is displaying.
- If there is any problem in the system, the driver's temperature indicator will light up the segment (A through P) corresponding to the error. The temperature indicator will then alternate every second between displaying "88" (all segments lit) and the error code segment (A through P). To determine the meaning of the DTC, refer to checking for DTCs.
- If there are no problems detected, the segments do not illuminate, and the system appear to be turned off.





Canceling the Self-Diagnostic Function

- 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.

Checking for DTCs

The temperature display indicates single or multiple DTCs. If indicator segments A, C, E and G are on at the same time, there may be an open in the common ground wire. If no DTCs are present, the indicator remains blank.










*: Each indication by segment lit on digital segments is assigned for 2 failure causes that it is necessary to decide which one is a true cause. If there is a failure in the sensor or motor, a value correspondent to the sensor or motor in the Sensor Input Display Mode is displayed as "Er", which serves to specify which is a true cause.

Displaying Sensor Inputs at the Climate Control Unit

The climate control unit has a mode that displays 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 knob to the desired test temperature. When selecting the test temperature, note these items:

- "Lo" temperature setting will default to MAX COOL, VENT, and RECIRC.
- "Hi" temperature setting will default to MAX HOT, HEAT, and FRESH.
- 58 through 86 °F 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).

2. Press and hold both the AUTO and REC buttons, then start the engine.

3. After the engine starts, release the buttons. The audio-HVAC display panel 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 refer to checking DTCs by DTC indication to check for DTCs.

- 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 with a known-good sensor, and recheck.





Celsius to Fahrenheit Conversion Table










Alphanumeric Conversion Table





Alphanumeric Conversion Table (Mode Positioning)





5. To cancel the sensor input display mode, press the AUTO button or turn the ignition switch to LOCK (0).