6E–177
3.2L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0502 (Flash DTC=24) VSS No Signal
060RW052
Circuit Description
The vehicle speed sensor has a magnet rotated by the
transmission output shaft. Attached to the sensor is a hall
effect circuit the interacts with the magnetic field treated
by the rotating magnet. A 12-volt operating supply for the
speed sensor hall circuit is supplied from the meter fuse.
The VSS pulses to ground the 9-volt signal sent from the
engine control module (ECM) on the reference circuit.
The ECM interprets vehicle speed by the number of
pulses to ground per second on the reference circuit.
Conditions for Setting the DTC
D
Engine is running.
D
Engine speed is below 5000 RPM.
D
Fuel is cutting.
D
Vehicle speed is below 1Km/H for more than 4 second.
Action Taken When the DTC Sets
D
The ECM will illuminate the malfunction indicator lamp
(MIL) the first time the fault is detected.
D
The ECM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC
D
The ECM will turn the MIL “OFF” on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.
D
A history DTC P0502 will clear after 40 consecutive
warm-up cycles have occurred without a fault.
D
DTC P0502 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the ECM battery
feed.