With OBD II Scantool/Honda PGM Tester

When the D4 indicator light has been reported on, connect the OBD II Scan Tool conforming to SAE J1978 or Honda PGM Tester to the DLC (16P). Turn the ignition switch ON, and observe the DTC on the screen of the OBD II Scan Tool or Honda PGM Tester. After determining the DTC, refer to Trouble Code Charts.

NOTE: See the OBD II Scan Tool or Honda PGM Tester user's manual for specific instructions.