DTC 22-01: Engine Speed Signal

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

Start the engine.
Check the ENGINE SPEED in the EPS DATA LIST with the HDS.
Is 0-300 RPM indicated?

YES -Go to step 3.

NO -Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the ECM/PCM and 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) terminal No. 3 and body ground.

Fig 1: Checking Continuity Between EPS Control Unit Connector A (11P) Terminal No. 3 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair a short to body ground in the wire between the EPS control unit and the ECM/PCM.

NO -Go to step 8.
Check for continuity between EPS control unit connector A (11P) terminal No. 3 and ECM/PCM connector A (44P) terminal No. 28.

Fig 2: Checking Continuity Between EPS Control Unit Connector A (11P) Terminal No. 3 And ECM/PCM Connector A (44P) Terminal No. 28
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Go to step 9.

NO -Repair an open in the wire between the EPS control unit and the ECM/PCM.
Reconnect ECM/PCM connector A (44P).
Turn the ignition switch to ON (II).
Measure the voltage between EPS control unit connector A (11P) terminal No. 3 and body ground.

Fig 3: Measuring Voltage Between EPS Control Unit Connector A (11P) Terminal No. 3 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

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 -Update the ECM/PCM if it does not have the latest software (see ELD REPLACEMENT ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then go to step 1 and recheck. If the ECM/PCM was updated and DTCs are not indicated, troubleshooting is complete. If the ECM/PCM was substituted and DTCs are not indicated, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ).