DTC 25-121, 26-121, 28-121

DTC 25-121  : Yaw Rate Sensor (Inside of Modulator-Control Unit) Output Signal Malfunction

DTC 26-121  : Lateral Acceleration Sensor (Inside of Modulator-Control Unit) Output Signal Malfunction

DTC 28-121  : Longitudinal Acceleration Sensor (Inside of Modulator-Control Unit) Output Signal Malfunction

NOTE: 

• Before you troubleshoot, review the general troubleshooting information .
• The yaw rate-acceleration sensor is built into the VSA modulator-control unit.
• Before troubleshooting, check the VSA modulator-control unit for proper mounting. Improper mounting of the VSA modulator-control unit may set these codes.

DTCs (VSA)

1. Problem verification

   -1. Turn the vehicle to the ON mode.

   -2. Clear the DTC with the HDS.

   -3. Turn the vehicle to the OFF (LOCK) mode.

   -4. Test-drive the vehicle at 9 mph (15 km/h) or more.

   NOTE:  Drive the vehicle on the road, not on a lift.

   -5. Check for DTCs with the HDS.

   DTC Description	DTC	Freeze Frame
   25-121 Yaw Rate Sensor (Inside of Modulator-Control Unit) Output Signal Malfunction
   26-121 Lateral Acceleration Sensor (Inside of Modulator-Control Unit) Output Signal Malfunction
   28-121 Longitudinal Acceleration Sensor (Inside of Modulator-Control Unit) Output Signal Malfunction

   Is DTC 25-121, 26-121, or 28-121 indicated?

   YES 

   The failure is duplicated. Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting .

2. VSA modulator-control unit check (update)

   -1. Update the VSA modulator-control unit if it does not have the latest software .

   -2. Turn the vehicle to the OFF (LOCK) mode.

   -3. Test-drive the vehicle at 9 mph (15 km/h) or more.

   NOTE:  Drive the vehicle on the road, not on a lift.

   -4. Check for DTCs with the HDS.

   DTC Description	DTC	Freeze Frame

   Is DTC 25-121, 26-121, or 28-121 indicated?

   YES 

   Check for loose terminals in the VSA modulator-control unit 21P connector. If the VSA modulator-control unit was updated and the symptom/indication is still present, replace the VSA modulator-control unit .

   NO 

   Troubleshooting is complete. If any other DTCs are indicated, go to the indicated DTCs troubleshooting.