F 350 4WD Pickup V8-7.3L DSL Turbo VIN F (1994)
Vehicle Speed Sensor: Testing and Inspection
Vehicle Speed Sensor Schematic
DESCRIPTION
The Vehicle Speed Sensor (VSS) is a variable reluctance sensor that generates a waveform with a frequency that is proportional to vehicle speed.
When the vehicle is moving slowly, the sensor produces a low frequency signal. As the vehicle speed increases, the sensor produces a higher
frequency signal. The Powertrain Control Module (PCM) uses this signal to control fuel injection, ignition timing and transmission/transaxle shift
points. This Pinpoint Test is intended to diagnose only the following:
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VSS Harness Circuits
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Vehicle Speed Sensor
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PCM
Test DP1 - Continuous Code 29/452: Complete VSS Drive Cycle
