DTC 28-120

DTC 28-120  : Longitudinal Acceleration Sensor (Inside of Modulator-Control Unit) Stuck

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 this code.

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 6 mph (10 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
   28-120 Longitudinal Acceleration Sensor (Inside of Modulator-Control Unit) Stuck

   Is DTC 28-120 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. Longitudinal acceleration sensor performance check

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Test-drive the vehicle.

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

   -3. Check the parameter(s) below with the HDS.

   Signal	Current conditions
   	Values	Unit
   LONGITUDINAL ACCELERATION SENSOR

   Does the indicated value change while accelerating or braking?

   YES 

   The system is OK at this time.

   NO 

   Go to step 3.

3. 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 6 mph (10 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 28-120 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.