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 ESC Module not only if the vehicle speed is low or high but also if the vehicle is or is not moving. Then, ESC Module informs PCM of these information.
The PCM 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 PCM 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 PCM 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 | 1. Open or short in harness 2. Poor connection or damaged harness 3. 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 |
•
60 Seconds | |
MIL On Condition |
•
2 Drive Cycles |
