DTC 25: Yaw Rate Sensor Malfunction: DTC 26: Lateral Acceleration Sensor Malfunction: DTC 104: Yaw Rate-Lateral Acceleration Sensor Malfunction

WARNING: This page is about a different car, the 2011 Honda Insight and 2010 Honda Insight. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).

Turn the ignition switch to ON (II).
Clear the DTC with the HDS.
Turn the ignition switch to LOCK (0), then turn it to ON (II) again.
Test-drive the vehicle around a number of corners.
NOTE: Drive the vehicle on the road, not on a lift.
Check for DTCs with the HDS.
Is DTC 25,26, or 104 indicated?

YES -Go to step 6.

NO -Intermittent failure, the system is OK at this time. Check for loose terminals between the yaw rate-lateral acceleration sensor 4P connector and the VSA modulator-control unit 47P connector. Refer to intermittent failures troubleshooting (see DIAGNOSTIC TROUBLE CODE (DTC) ).
Check the size, air pressure, and the amount of wear of all four tires.
Is the tire condition and wheel alignment OK?

YES -Go to step 7.

NO -Replace the tires and/or adjust the air pressure, then recheck by test-driving.
Check the YAW/G SENSOR DIAGNOSIS in the VSA FREEZE DATA with the HDS.
Is YAW/G COMBINE SENSOR DIAGNOSIS NORMAL?

YES -Go to step 13.

NO -Go to step 8.
Turn the ignition switch to LOCK (0).
Disconnect the yaw rate-lateral acceleration sensor 4P connector (see YAW RATE-LATERAL ACCELERATION SENSOR REPLACEMENT ).
Turn the ignition switch to ON (II).
Measure the voltage between yaw rate-lateral acceleration sensor 4P connector terminals No. 1 and No. 4.

Fig 1: Measuring Voltage Between Yaw Rate-Lateral Acceleration Sensor 4P Connector Terminals No. 1 And No. 4
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Replace the yaw rate-lateral acceleration sensor (see YAW RATE-LATERAL ACCELERATION SENSOR REPLACEMENT ).

NO -Go to step 12.
Measure the voltage between yaw rate-acceleration sensor 4P connector terminal No. 1 and body ground.

Fig 2: Measuring Voltage Between Yaw Rate-Acceleration Sensor 4P Connector Terminals No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Repair an open in the wire between the yaw rate-acceleration sensor and body ground (G502).

NO -Repair an open in the wire between the yaw rate-acceleration sensor and the under-dash fuse/relay box.
Turn the ignition switch to LOCK (0).
Disconnect the under-dash fuse/relay box connector Q(16P).
Turn the ignition switch to ON (II).
Measure the voltage between yaw rate-lateral acceleration sensor 4P connector terminals No. 1 and No. 4.

Fig 3: Measuring Voltage Between Yaw Rate-Lateral Acceleration Sensor 4P Connector Terminals No. 1 And No. 4
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 18.

NO -Go to step 17.
Measure the voltage between yaw rate-lateral acceleration sensor 4P connector terminal No. 1 and body ground.

Fig 4: Measuring Voltage Between Yaw Rate-Lateral Acceleration Sensor 4P Connector Terminal No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Repair an open in the wire between the yaw rate-acceleration sensor and body ground (G502).

NO -Repair an open in the wire between the yaw rate-lateral acceleration sensor and the under-dash fuse/relay box.
Check the wheel alignment (see WHEEL ALIGNMENT ).
Is the wheel alignment OK?

YES -Go to step 19.

NO -Make sure the suspension is not modified, and adjust the wheel alignment correctly, and recheck by test-driving.
Substitute a known-good yaw rate-lateral acceleration sensor (see YAW RATE-LATERAL ACCELERATION SENSOR REPLACEMENT ).
Reconnect all connectors.
Turn the ignition switch to ON (II).
Clear the DTC with the HDS.
Turn the ignition switch to LOCK (0).
Test-drive the vehicle around a number of corners.
NOTE: Drive the vehicle on the road, not on a lift.
Check for DTCs with the HDS.
Is DTC 25, 26, or 104 indicated?

YES -Go to step 26.

NO -Replace the original yaw rate-lateral acceleration sensor (see YAW RATE-LATERAL ACCELERATION SENSOR REPLACEMENT ).
Update the VSA modulator-control unit if it does not have the latest software (see VSA MODULATOR-CONTROL UNIT UPDATE ). If the unit already has the latest software, substitute a known-good VSA modulator-control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ).
Turn the ignition switch to LOCK (0).
Test-drive the vehicle around a number of corners.
NOTE: Drive the vehicle on the road, not on a lift.
Check for DTCs with the HDS.
Is DTC 25, 26, or 104 indicated?

YES -Check for loose terminals in the VSA modulator-control unit 47P connector. If the VSA modulator-control unit was updated, substitute a known-good VSA modulator-control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), then retest. If the VSA modulator-control unit was substituted; Go to step 1.

NO -If the VSA modulator-control unit was updated, troubleshooting is complete. If the VSA modulator-control unit was substituted, replace the original VSA modulator-control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ). If any other DTCs are indicated, go to the indicated DTCs troubleshooting.