DI_a232 — Velocity Estimator Degraded

Full alert identifier: DI_a232_velocityEstimatorDegraded

Alert description

The drive interface (DI) electronic control unit (ECU) detects that the accuracy of the velocity estimator is degraded. Velocity estimate is required for traction control and stability control.

Potential impact

Traction control and stability control are unavailable, requiring greater manual input from the driver.

Set condition

The DI ECU detects that some or all velocity estimate inputs are unavailable. Check for corresponding ECU missing (MIA) alerts from DI and other ECUs to help identify the cause of the controller area network (CAN) issue.

Clear condition

The DI ECU detects that all of the velocity estimator's inputs are available.

Signals to check

These diagnostic fields are associated with DI_a232. Check the alert's Alert Log in Service Mode Plus for available values.

Signal	Unit
Abs Brake Event Active Valid `DI_a232_AbsBrakeEventActiveValid` 0 INVALID 1 VALID	—
Brake Master Cyl Press Valid `DI_a232_BrakeMasterCylPressValid` 0 INVALID 1 VALID	—
Oversteer Active Valid `DI_a232_OversteerActiveValid` 0 INVALID 1 VALID	—
UI Traction Control Mode `DI_a232_UI_tractionControlMode` 0 NORMAL SELECTED 1 SLIP START SELECTED 2 DEV MODE 1 SELECTED 3 DEV MODE 2 SELECTED 4 ROLLS MODE SELECTED 5 DYNO MODE SELECTED 6 OFFROAD ASSIST SELECTED	—
Understeer Active Valid `DI_a232_UndersteerActiveValid` 0 INVALID 1 VALID	—
Wheel Brake Torques Valid `DI_a232_WheelBrakeTorquesValid` 0 INVALID 1 VALID	—
All Motor Torques Valid `DI_a232_allMotorTorquesValid` 0 INVALID 1 VALID	—
All Whl Speed Rotation Avail `DI_a232_allWhlSpeedRotationAvail` 0 UNAVAILABLE 1 AVAILABLE	—

Show 8 more fields

Signal	Unit
Lateral Accel Valid `DI_a232_lateralAccelValid` 0 INVALID 1 VALID	—
Longitudinal Accel Valid `DI_a232_longitudinalAccelValid` 0 INVALID 1 VALID	—
Musurf `DI_a232_musurf`	—
Musurf High `DI_a232_musurfHigh`	—
Steer Angle Valid `DI_a232_steerAngleValid` 0 INVALID 1 VALID	—
Vehicle Velocity `DI_a232_vehicleVelocity`	m/s
Velocity Estimator State `DI_a232_velocityEstimatorState` 0 NOT INITIALIZED 1 WHEELS NORMAL 2 WHEELS REDUCED 3 BACKUP WHEELS A 4 BACKUP WHEELS B 5 BACKUP MOTOR	—
Yaw Rate Valid `DI_a232_yawRateValid` 0 INVALID 1 VALID	—

Check other alerts

With Service Mode Plus enabled, open Service Alerts → All. Review the other alerts for clues to the cause of DI_a232.