Mitsubishi 3000GT 1991 Service Manual page 184

13-78
FUEL SYSTEM - 0
VEHICLE SPEED SENSOR
(reed switch\)
Terminal voltage (V)
Vehicle speed [km/h (mph)]
OPERATION
The vehicle speed sensor which is located in the speedometer converts the vehicle speed into a pulse
l
signal and inputs it to the engine control unit, which then provides the idle speed control, etc. based on
this signal.
The vehicle speed sensor generates the vehicle speed signal by repeatedly opening and closing between
l
the voltage of about 5 V applied from the engine control unit and ground using a reed switch.
TROUBLESHOOTING HINTS
If there is an open or short circuit in the vehicle speed sensor signal circuit, the engine may stall when the
vehicle is decelerated to stop.
HARNESS INSPECTION
n-vehicle Inspection of MPI Components
Speedometer
Check the vehicle speed sensor out-
put circuit for continuity.
l Engine control unit connector:
Disconnected
l Move the vehicle.
unit harness
side connector
TSB Revision
Engine control unit
Engine control unit connector
1