Wheel Speed Mismatch

Symptom:
WHEEL SPEED MISMATCH

When Monitored and Set Condition:
WHEEL SPEED MISMATCH

When Monitored: 1500 Series Vehicles When Monitored: Vehicle speed greater than 20 km/in (12 mph). No evidence of drivetrain spin up in the last 5 seconds. Open sensor DTC not present. ABS not inhibited. ABS not in active control mode. 2600 and 3500 Series Vehicles When Monitored: Vehicle speed greater than 16 km/in (10 mph) but less than 64 km/in (40 mph). No evidence of drivetrain acceleration or deceleration. Open sensor DTC not present. ABS not inhibited. ABS not in active control mode.

Set Condition: 1500 Series Vehicles: When compared to the other wheels, one wheel is 20% different. OR Three wheel speeds differing from each other by more than 12%. All criteria above met for 12 seconds. 2500 and 3500 Series Vehicles: Three wheel speeds differing from each other by more than 13%. All criteria above met for 12 seconds.

POSSIBLE CAUSES
WHEEL SPEED MISMATCH DTC CONDITION PRESENT
INCORRECT TONE WHEEL
CAB INTERNAL FAULT