Mitsubishi Pajero Pinin. Manual - part 56

GDI –

Troubleshooting

13A-90

EGR VALVE (STEPPER MOTOR)

Measurement Method

Disconnect the EGR valve connector, and connect the
special tool (test harness: MB991658) in between.

Connect the analyzer special patterns pickup to the EGR
valve-side connector terminal 1, terminal 3, terminal 4
and terminal 6 respectively.

Alternate Method (Test harness not available)

Connect the analyzer special patterns pickup to
engine-ECU terminal 34, connection terminal 32,
connection terminal 6, and connection terminal 5
respectively.

Standard Wave Pattern

Observation conditions

Function

Special patterns

Pattern height

High

Pattern selector

Display

Engine condition

Racing

Standard wave pattern

(V)

The wave pattern
appears for an
instant, but soon
disappears.

Point B
Coil reverse electromo-
tive force (Approx. 3

10V)

Point A
Induced electromotive force
from the motor turning

Time

EGR
valve
control
signal
wave
pattern

Special
patterns
pickup

Analyzer

GDI –

Troubleshooting

13A-91

Wave Pattern Observation Points

Check that the standard wave pattern appears when the EGR control servo is operating.
Point A:

Presence or absence of induced electromotive force from the motor turning. (Refer to the abnormal

wave pattern.)

Contrast with standard wave pattern

Probable cause

Induced electromotive force does not appear or is extremely small.

Motor is malfunctioning

Point B:

Height of coil reverse electromotive force

Contrast with standard wave pattern

Probable cause

Coil reverse electromotive force does not appear or is extremely small.

Short in the coil

Examples of Abnormal Wave Pattern

Example 1

Cause of problem

Motor is malfunctioning. (Motor is not operating.)

Wave pattern characteristics

Induced electromotive force from the motor turning does
not appear.

Example 2

Cause of problem

Open circuit in the line between the EGR valve and the
engine-ECU

Wave pattern characteristics

Current is not supplied to the motor coil on the open circuit
side. (Voltage does not drop to 0 V.)
Furthermore, the induced electromotive force waveform
at the normal side is slightly different from the normal
waveform.

Open
circuit
side

Nor-
mal
side

GDI –

On-vehicle Service

13A-92

ON-VEHICLE SERVICE

Caution
(1) Never attempt to tamper the fixed SAS. The fixed SAS

is precisely adjusted at factory.

(2) Should it be tampered, the full closed position of the

throttle valve will be changed. This causes the
engine-ECU to learn a wrong position of the throttle
valve.

THROTTLE BODY (THROTTLE VALVE ARE)
CLEANING

Start the engine, and warm it up until engine coolant
temperature reaches 80

C. Then stop the engine.

Remove the air intake hose at the throttle body side.

Apply cleaning agent to the throttle valve through the intake
port of the throttle valve, and then leave it for approx.
five minutes.

Start the engine, race it several times, and then let it run
at idle for approx. one minute.

If carbon deposits are not removed from the throttle vale
area, repeat steps 3 and 4.

Install the air intake hose.

Use the MUT-

or disconnect the negative battery cable

from the battery terminal in order to erase a diagnosis
code. Wait for at least ten seconds, and then let the engine
run at idle again for approx. ten minutes.

THROTTLE POSITION SENSOR ADJUSTMENT

Connect the MUT-

to the diagnosis connector.

When not using the MUT-

II,

proceed as follows:

(1) Disconnect the throttle position sensor connector, and

connect the special tool (test harness: MB991536)
between the disconnected connector taking care not
to confuse the terminal to be connected.

(2) Connect digital voltmeter between the terminal No.2

(sensor output: blue clip of special tool) and the
terminal No.3 (sensor earth: white clip of special tool)
of the throttle position sensor connector.

Fixed SAS

Equipment side connector

Throttle
position
sensor

MB991536

Throttle posi-
tion sensor

GDI –

On-vehicle Service

13A-93

Disconnect the throttle valve control servo connector.

Turn the ignition switch to ON (but do not start the engine).

Check the output voltage of the throttle position sensor
(1st channel) when the throttle valve is fully closed by
your finger.

Standard value: 0.4 – 0.6 V

If not within the standard value, loosen the throttle position
sensor mounting bolts. Then rotate the sensor body to
adjust.

Check the output voltage of the throttle position sensor (2nd
channel) when the throttle valve is fully closed by your
finger. When not using the MUT-

, connect digital voltmeter

between the terminal No.4 (sensor output: black clip of
special tool) and the terminal No.3 (sensor earth: white clip
of special tool) of the throttle position sensor connector.

Standard value: 4.2 – 4.8 V

If not within the standard value, replace the throttle position
sensor.

Turn the ignition switch to OFF.

Reconnect the throttle valve control servo connector.

10. Remove the MUT-

. If the MUT-

is not used, remove

the special tool, and then connect the throttle position
sensor connector.

11. If a diagnosis code is displayed, erase the diagnosis code

by using the MUT-

or disconnect the negative battery

cable from the battery terminal and then leave it for at
least ten seconds. After that, reconnect the battery cable.

12. Turn the ignition switch to ON and return it to OFF, and

then leave it for at least ten seconds. In addition, if the
battery cable is disconnected at step 11, let the engine
run at idle for approx. ten minutes.

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