P0503 CHEVROLET - Vehicle Speed Sensor Circuit Intermittent
When is the code detected?When the Powertrain Control Module (PCM) detects an unrealistically large drop in the vehicle speed, then DTC P0503 sets.
P0503 Chevrolet DescriptionThe Vehicle Speed Sensor (VSS) assembly provides vehicle speed information to the Powertrain Control Module (PCM). The VSS assembly is a Permanent Magnet (PM) generator. The PM generator produces a pulsing AC voltage as rotor teeth on the transmission output shaft pass through the sensor's magnetic field. The AC voltage level and the number of pulses increase as the speed of the vehicle increases. The PCM converts the pulsing voltage to vehicle speed. The PCM uses the vehicle speed signal to determine shift timing and torque converter clutch (TCC) scheduling.