DTC 23-04: CAN Bus-Off Malfunction

NOTE: Check for any powertrain DTCs and troubleshoot those first.

Turn the ignition switch to ON (II).
Clear the DTC with the HDS.
Turn the ignition switch to LOCK (0).
Start the engine.
Check for DTCs with the HDS.
Is DTC 23-04 indicated?

YES -Go to step 6.

NO -Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the EPS control unit.
Turn the ignition switch to LOCK (0).
Short the SCS line with the HDS.
Disconnect ECM/PCM connector A (44P) (see step 14 on ECM/PCM REPLACEMENT ).
Disconnect EPS control unit connector A (11P) (see step 3 ).

Check for continuity between EPS control unit connector A (11P) terminals and ECM/PCM connector A (44P) terminals (see table).

CONNECTOR TERMINAL DESCRIPTION

Sign	EPS Control Unit Connector A (11P) Terminal	ECM/PCM Connector A (44P) Terminal
F-CAN L	No. 9	No. 37
F-CAN H	No. 7	No. 36

Fig 1: Checking Continuity Between EPS Control Unit Connector A (11P) Terminals And ECM/PCM Connector A (44P) Terminals

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Check for loose terminals in the EPS control unit connectors, and repair if necessary. If no poor connections are found, replace the EPS control unit (see EPS CONTROL UNIT REMOVAL/INSTALLATION ).

NO -Repair an open in the wire between the EPS control unit and the ECM/PCM.