Aerostar 2WD V6-182 3.0L (1995)
Vehicle Speed Sensor: Description and Operation
PURPOSE
The Programmable Speedometer/Odometer Module (PSOM) provides a vehicle speed signal input to:
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Powertrain Control Module (PCM)
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Speed Control Servo Amplifier
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Instrument Cluster
The speed signal is used by the PCM to determine transmission shift points and torque converter clutch operation.
OPERATION
The PSOM receives a vehicle speed signal from the RABS Differential Speed Sensor (DSS) on pin 4 DSS input, and pin 5 DSS return. It converts
this signal to a standard 8000 pulses-per-mile speed signal output. This output signal is sent to the PCM on PSOM pin 7.
The PSOM receives two power supply inputs. Pin 1 receives a continuous 12.0 volt input while pin 3 receives a 12.0 volt input only when the
ignition switch is in run.
NOTE: Vehicle speed is determined by the RABS Differential Speed Sensor. For additional information, See: Brakes and Traction Control/Antilock
Brakes / Traction Control Systems/Wheel Speed Sensor
