Vehicle Speed Sensor: Description and Operation

VEHICLE SPEED SENSOR - PCM INPUT

Fig. 9 Vehicle Speed Sensor, Skip Shift Solenoid And Reverse Lockout Solenoid:

The vehicle speed sensor is located on the drivers side of the transmission.

The Power Control Module (PCM) determines vehicle speed from the speed sensor input.

From the speed sensor input to the PCM determine the following:
- To prevent deceleration fuel cutoff at low vehicle speeds
- What gear the vehicle is operating in for 2-3 lockout
- Idle speed control delay time based on whether the vehicle is moving
- Cooling fan turns off at 77 mph, when accelerating, and turns back on at 67 mph.