VSA System

Control System DTCs

VSA DTC Troubleshooting: 25-121

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

NOTE:
* Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information Reading and Clearing Diagnostic Trouble Codes.
* The yaw rate-acceleration sensor is built into the VSA modulator-control unit.
* Before troubleshooting, check the VSA modulator-control unit for proper mounting. If not properly installed the VSA modulator-control unit may set these codes.

1. Problem verification:

Problem verification
-1. Turn the ignition switch to ON (II).

-2. Clear the DTC with the HDS.

-3. Turn the ignition switch to LOCK (0).

-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.

Is DTC 25-121 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):

VSA modulator-control unit check (update)
-1. Update the VSA modulator-control unit if it does not have the latest software Programming and Relearning.

-2. Turn the ignition switch to LOCK (0).

-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.

Is DTC 25-121 indicated?
-YES- Check for loose terminals in the VSA modulator-control unit 22P connector. If the VSA modulator-control unit was updated and the symptom/indication is still present, replace the VSA modulator-control unit Service and Repair.
-NO- Troubleshooting is complete. If any other DTCs are indicated, go to the indicated DTCs troubleshooting.