Possible causes

– Faulty Vehicle Speed Sensor
– Vehicle speed sensor harness or connectors is open or shorted
– Vehicle speed sensor circuit poor electrical connection
– Faulty Powertrain Control Module (PCM)

When is the code detected?

The almost 0 km/h (0 MPH) signal from vehicle speed sensor is sent to Powertrain Control Module (PCM) even when vehicle is being driven.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Speedometer may not work properly
– Transmission shifting problem

P0500 PONTIAC Description

A toothed wheel mounted on the output shaft of the transmission generates an AC voltage pulse as it moves past the Vehicle Speed Sensor (VSS). The VSS contains a permanent magnet surrounded by a coil of wire, which produces a magnetic field. The toothed wheel interrupts the magnetic field this generates an AC voltage pulse. As the vehicle speed increases the AC voltage pulse rate also increases. The Powertrain Control Module (PCM) determines the vehicle speed based on the frequency of these pulse signals.

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