The Wheel Speed Sensor (WSS) generates a waveform with a frequency proportional to the speed of the vehicle. The signal generated by the WSS informs the ABS/ESP Module not only if the vehicle speed is low or high but also if the vehicle is or is not moving. Then, ABS/ESP Module informs ECM of these information. The ECM uses these information to control the fuel injection, ignition timing, transaxle shift scheduling and torque converter clutch scheduling. The WSS signal is also used to detect rough road conditions.
The ECM evaluates engine speed and mass air flow if there is no vehicle speed signal. This evaluation of both values will detect open circuit or short circuit errors on the wheel speed sensor. The ECM sets DTC P2159 if there is no vehicle speed signal from wheel speed sensor while both engine speed and mass air flow are higher than predetermined threshold during the predetermined time
Item
Detecting Condition
Possible Cause
DTC Strategy
Plausibility Check
Open or short in harness
Poor connection or damaged harness
VSS
Enable Conditions
Engine speed > 2100rpm
Air mass flow > 0.44g/rev.
No fuel injection shut off
Coolant Temp. > 60?(140?)
Threshold Value
VSS = 0 with high engine speed and load
Diagnostic Time
60sec.
MIL On Condition
2 Driving Cycles