Mitsubishi 1989-1993 GALANT Service Manual page 300

FUEL SYSTEM (SOHC-16 VALVE>
OPERATION
The throttle position sensor converts the throttle
position opening into a voltage and inputs it to the
engine control module, which
fuel injection, based on the input signal.
The 5V power in the engine control module is
l
supplied to the throttle position sensor. It flows
through the resistor in the sensor and is then
grounded in the engine control module.
As the throttle valve shaft rotates from the idle
l
position to wide open position, the resistance
between the variable resistor terminal of the
throttle position sensor and the ground terminal
increases. As a result, the voltage at the throttle
position sensor variable resistance terminal also
increases.
INSPECTION
Using Scan Tool
Function item No.
Data display
Sensor
14
Data
voltage
reading
HARNESS INSPECTION
connector
side connetor
condition
Check
ON
Check continuity of the ground
for
circuit.
Throttle position sensor connector:
l
Disconnected
Check for an open-circuit, or a short-
circuit to ground between the engine
control module and the throttle posi-
tion sensor.
Throttle position sensor connector:
l
Disconnected
Engine control module connec-
l
ECM
Disconnected
tor:
harness side
TSB Revision
On-Vehicle Inspection of
TROUBLESHOOTING HINTS
Hint 1: The throttle position sensor signal is more
important in the control of automatic trans-
axle than in the engine control. Shifting
shock and other troubles will be caused if
this sensor is faulty.
Hint 2: If the output voltage of the throttle position
sensor is out of specification, adjust the
sensor and check the voltage again.
If there is an evidence of disturbed fixed SAS
setting, adjust the fixed SAS.
Throttle valve
At idle position
Open slowly
Open widely
Standard value
300
Increases with valve
opening
4,500 - 5,500 mV
Repair the
harness.
Repair the
harness.