DTC P1659: Electronic Throttle Control System (ETCS) Control Relay OFF Malfunction
- Turn the ignition switch ON (II).
- Clear the DTC with the HDS.
- Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1659 indicated?
YES - Go to step 4.
NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the ETCS control relay and the ECM.
- Turn the ignition switch OFF.
- Check the No. 21 DBW (THROTTLE ACTUATOR CONTROL) (15 A) fuse in the under-hood fuse/relay box.
Is the fuse OK?
YES - Go to step 6.
NO - Go to step 17.
- Remove the ETCS control relay (F) from the under-hood fuse/relay box.
- Test the ETCS control relay (see POWER RELAY TEST
).
Is the ETCS control relay OK?
YES - Go to step 8.
NO - Replace the ETCS control relay, then go to step 23.
- Turn the ignition switch ON (II).
- Measure voltage between ETCS control relay 4P connector terminal No. 4 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES - Go to step 10.
NO - Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ), then go to step 22.
- Measure voltage between ETCS control relay 4P connector terminal No. 1 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES - Go to step 11.
NO - Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ), then go to step 22.
- Turn the ignition switch OFF.
- Jump the SCS line with the HDS.
- Disconnect ECM connector C (44P).
- Check for continuity between ETCS control relay 4P connector terminal No. 2 and ECM connector terminal C1.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES - Go to step 15.
NO - Repair open in the wire between the ECM (CD and the ETCS control relay, then go to step 23.
- Disconnect ECM connector A (44P).
- Check for continuity between ETCS control relay 4P connector terminal No. 3 and ECM connector terminal A20.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES - Go to step 28.
NO - Repair open in the wire between the ECM (A20) and the ETCS control relay, then go to step 23.
- Remove the ETCS control relay (F) from the understood fuse/relay box.
- Jump the SCS line with the HDS.
- Disconnect ECM connector C (44P).
- Check for continuity between ECM connector terminal C1 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES - Repair short in the wire between the ECM (C1) and the ETCS control relay, then go to step 23.
NO - Go to step 21.
- Check for continuity between ETCS control relay 4P connector terminal No. 1 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES - Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ), then go to step 23.
NO - Go to step 28.
- Turn the ignition switch OFF.
- Reconnect all connectors.
- Turn the ignition switch ON (II).
- Reset the ECM with the HDS.
- Do the ECM idle learn procedure (see ECM IDLE LEARN PROCEDURE ).
- Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1659 indicated?
YES - Check for poor connections or loose terminals at the ETCS control relay and the ECM, then go to step 1.
NO - Troubleshooting is complete. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTCs troubleshooting.
- Reconnect all connectors.
- Update the ECM if it does not have the latest software (see ECM UPDATE ), or substitute a known-good ECM (see SUBSTITUTING THE ECM ).
- Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1659 indicated?
YES - Check for poor connections or loose terminals at the ETCS control relay and the ECM. If the ECM was updated, substitute a known-good ECM (see SUBSTITUTING THE ECM ), then recheck. If the ECM was substituted, go to step 1.
NO - If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM (see ECM REPLACEMENT ). If any other Pending or Confirmed DTCs are indicated, go to the indicated DTCs troubleshooting.