Mitsubishi Montero Sport (2004+). Manual — part 121

AUTO-CRUISE CONTROL

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ENGINE AND EMISSION CONTROL

17-79

STEP 3. Using scan tool MB991958, check data list item 04:
auto-cruise control "CANCEL" switch.

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Using scan tool MB991958.
(2) Connect scan tool MB991958 to the data link connector.
(3) Set scan tool MB991958 to data reading mode for

auto-cruise control system item 04, auto-cruise control
"CANCEL" switch.

• When auto-cruise control "CANCEL" switch is at the ON

position, the display on scan tool MB991958 should be
"ON".

• When auto-cruise control "CANCEL" switch is at the

OFF position, the display on scan tool MB991958
should be "OFF".

(4) Turn the ignition switch to the "ON" position.
Q: Is the switch operating properly?

YES : Go to Step 4 .
NO : Go to Diagnostic Trouble Code Procedures number

15 (Refer to

P.17-34

).

STEP 4. Using scan tool MB991958, check data list item 05:
stoplight switch.

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Using scan tool MB991958.
(2) Connect scan tool MB991958 to the data link connector.
(3) Set scan tool MB991958 to data reading mode for

auto-cruise control system item 05, stoplight switch.

• When brake pedal is depressed, the display on scan

tool MB991958 should be "ON".

• When brake pedal is released, the display on scan tool

MB991958 should be "OFF".

(4) Turn the ignition switch to the "ON" position.
Q: Is the switch operating properly?

YES : Go to Step 5 .
NO : Go to Symptom Procedures number 2 (Refer to

P.17-62

).

AK303629AB

MB991911

MB991827

MB991824

16-PIN

AK303629AB

MB991911

MB991827

MB991824

16-PIN

AUTO-CRUISE CONTROL

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ENGINE AND EMISSION CONTROL

17-80

STEP 5. Using scan tool MB991958, check data list item 14:
park/neutral position switch.

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Using scan tool MB991958.
(2) Connect scan tool MB991958 to the data link connector.
(3) Set scan tool MB991958 to data reading mode for

auto-cruise control system item 14, park/neutral position
switch.

• When selector lever is at the "P" or "N" position, the dis-

play on scan tool MB991958 should be "ON".

• When selector lever is other than "P" and "N" position,

the display on scan tool MB991958 should be "OFF".

(4) Turn the ignition switch to the "ON" position.
Q: Is the switch operating properly?

YES : Go to Step 6 .
NO : Go to Symptom Procedures number 3 (Refer to

P.17-71

).

STEP 6. Check that the malfunction is eliminated
Q: Is the malfunction eliminated?

YES : It can be assumed that this malfunction is intermittent.

(Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points

− How to

Cope with Intermittent Malfunction

P.00-7

).

NO : Replace the auto-cruise control-ECU. (Refer to

P.17-99

). Then go to Step 7 .

STEP 7. Check that the malfunction is eliminated
Q: Is the malfunction eliminated?

YES : This procedure is complete.
NO : Return to Step 1 .

AK303629AB

MB991911

MB991827

MB991824

16-PIN

AUTO-CRUISE CONTROL

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ENGINE AND EMISSION CONTROL

17-81

INSPECTION PROCEDURE 6: Hunting (Repeated Acceleration and Deceleration) Occurs at the Set
Vehicle Speed.

.

TECHNICAL DESCRIPTION (COMMENT)
The cause is probably the malfunction of the vehicle
speed sensor or incorrect vacuum in the auto-cruise
control vacuum pump or actuator.

.

TROUBLESHOOTING HINTS

• Malfunction of the vehicle speed sensor

• Malfunction of the auto-cruise control vacuum

pump

• Malfunction of the vacuum actuator (accelerator

lever body assembly)

• Malfunction of the auto-cruise control-ECU

DIAGNOSIS

Required Special Tool:

• MB991223: Harness set

STEP 1. Check the vehicle speed sensor.
(1) Disconnect the vehicle speed sensor connector B-09.

(2) Remove the vehicle speed sensor and connect a 3

− 10 kΩ

resistor as shown in the illustration.

(3) Turn the shaft of the vehicle speed sensor and check that

there is voltage between terminals 2

− 3 (one turn = four

pulses).

Q: Is the voltage within specifications?

YES : Go to Step 2 .
NO : Replace the vehicle speed sensor. Then go to Step 5 .

AC003458 AC

CONNECTOR: B-09
<RWD>

B-09 (B)

1

2

3

B-09: HARNESS
SIDE CONNECTOR

AC201841

3 2 1

CONNECTOR: B-09

AB

B-09: HARNESS
SIDE CONNECTOR

<4WD>

B-09 (B)

AC004754

TURN

SHAFT

OHMMETER

RESISTOR
3 - 10 k

Ω

AB

AUTO-CRUISE CONTROL

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ENGINE AND EMISSION CONTROL

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STEP 2. Check the auto-cruise vacuum pump.
(1) Disconnect the vacuum hose from the auto-cruise vacuum

pump and connect a vacuum gauge to the vacuum pump.

(2) Disconnect the vacuum pump connector A-02.

(3) Check the auto-cruise vacuum pump and valves according

to the following procedure:

• Connect the positive battery terminal to auto-cruise vac-

uum pump side connector A-02 terminal 1, and the neg-
ative battery terminal to terminals 2, 3, and 4. Then the
vacuum gauge should read 27 kPa (8.0 in Hg) or more.

• The vacuum should be maintained when auto-cruise

vacuum pump side connector A-02 terminal 4 is discon-
nected from the negative battery terminal while termi-
nals 1, 2, and 3 remain connected. Then the vacuum
gauge should read 0 kPa (0 in Hg) when terminal 2 is
disconnected from the negative battery terminal while
terminals 1, and 3 remain connected.

• The vacuum should be maintained when auto-cruise

vacuum pump side connector A-02 terminal 4 is discon-
nected from the negative battery terminal while termi-
nals 1, 2, and 3 remain connected. Then the vacuum
gauge should read 0 kPa (0 in Hg) when terminal 3 is
disconnected from the negative battery terminal while
terminals 1, and 2 remain connected.

Q: Are all of the above values satisfied?

YES : Go to Step 3 .
NO : Replace the auto-cruise vacuum pump. (Refer to

P.17-99

). Then go to Step 5 .

STEP 3. Check the vacuum actuator.
(1) Disconnect the vacuum hose from the vacuum actuator,

and then connect a hand vacuum pump to the vacuum
actuator.

(2) Apply a vacuum and check that the throttle lever moves and

the vacuum is maintained.

Q: Is the vacuum actuator damaged?

YES : Replace the vacuum actuator (accelerator lever body

assembly). (Refer to GROUP 13A, Throttle Body
Assembly

P.13A-903

). Then go to Step 5 .

NO : Go to Step 4 .

AC004746

CONNECTOR: A-02

HYDRAULIC
UNIT

AD

A-02 (B)

AC004749 AE

VACUUM GAUGE

A-02
HARNESS CONNECTOR:
AUTO CRUISE VACUUM
PUMP CONNECTOR SIDE

AC004774 AB

VACUUM
ACTUATOR