Rear Heater-A/C Control System

How to Retrieve a Diagnostic Trouble Codes 

The climate control unit has a self-diagnostic function. To run the self-diagnostic function, do the following:

1. Turn the ignition switch ON (II).
2. Turn the temperature control knob to LO for about 20 seconds, then HI for about 20 seconds.
3. Press the OFF button, then press the recirculation control button to select Recirculation (recirculation indicator comes on).
4. Press and hold the recirculation control button to select Fresh (recirculation indicator goes off). Continue to hold the button. The recirculation indicator comes on for 2 seconds, and then goes off.
   • If the system is OK, the recirculation indicator stays off.
   • If any trouble is found, the recirculation indicator blinks the diagnostic trouble code (DTC) to indicate a faulty circuit or component.
5. After recording the DTC, release the recirculation control button.

   To determine the meaning of the DTC, refer to the DTC troubleshooting index for rear heater-A/C control system.

   Fig 1: Identifying OFF Button & Recirculation Control Button

   Courtesy of AMERICAN HONDA MOTOR CO., INC.

   Example of DTC Indicator Pattern (DTC 2): 

   Fig 2: Identifying DTC Indicator Blinking Pattern

   Courtesy of AMERICAN HONDA MOTOR CO., INC.

Cancelling the Self-diagnostic Function 

6. Turn the ignition switch OFF to cancel the self-diagnostic function. After completing repair work, run the self-diagnostic function again to make sure that there are no other malfunctions.

In case of multiple problems, the recirculation indicator will indicate only the DTC with the least number of blinks.

In case of an intermittent failure, the climate control unit will store the DTC until the ignition switch is turned off.