Mitsubishi 1989 Galant, Service Manual

Page: 206 / 1273

FUEL SYSTEM VALVE>
Inspection of Components
IDLE SPEED CONTROL MOTOR POSITION SENSOR models>
Component side
speed control motor
connector
position sensor
l - F - - - -
@ Harness side I--
connector
1 3
Engine
control
module
module connector
Plunger stroke
OPERATION
l
The idle speed control motor position sensor
functions to convert the data concerning the
position of the plunger (located within the
speed control motor) to voltage, and to input
that voltage (as signals) to the engine control
module. The engine control module, based upon
those signals, then functions to regulate the
idle-speed control motor.
l
The power supply within the engine control
module is supplied to the idle speed control
position sensor; it then passes through the re-
sistance within the sensor and is grounded at
the engine control module.
TROUBLESHOOTING HINTS
Hint
The idle speed control motor position sensor is the
most important sensor for control of the idling
speed; there is very often a malfunction of this sen-
sor if a problem occurs when the load is
caused to fluctuate, such as when, during idling, the
air conditioning switch is switched back and forth
between OFF and ON, etc.
l
When the plunger located within the idle-speed
control motor extends from its contracted con-
dition, the resistance between the idle speed
control motor position sensor’s variable-resist-
ance terminal and the ground terminal also in-
creases in accordance with that extension. As a
result, the voltage of the idle speed control
motor position sensor’s variable-resistance ter-
minal also becomes higher in accordance with
the extension.
Hint 2:
If the output voltage of the idle speed control motor
position sensor deviates from the standard value
even though the results of the checking of the idle
speed control motor position sensor harness and of
the component itself are normal, the malfunction
may be presumed to be among the following:
TSB Revision