Mitsubishi Montero (2004+). Manual — part 408

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-39

SYMPTOM CHART

M1172002300407

SYMPTOM PROCEDURES

INSPECTION PROCEDURE 1: When the Brake Pedal is Depressed, Auto-cruise Control is not
Cancelled.

.

COMMENT
The stop light switch circuit is suspected.

.

TROUBLESHOOTING HINTS (The most likely
causes for this case:)

• Malfunction of the stoplight switch.

• Damaged harness or connector.

• Malfunction of the PCM.

DIAGNOSIS

.

Refer to

P.17-27

, Diagnostic Trouble Code Procedures

− DTC

22: Stoplight Switch System.

INSPECTION PROCEDURE 2: When the Selector Lever is Moved to "N" Range, Auto-cruise Control is
not Cancelled.

.

COMMENT
The transmission range switch circuit is suspected.

.

TROUBLESHOOTING HINTS (The most likely
causes for this case:)

• Malfunction of the transmission range switch.

• Damaged harness or connector.

• Malfunction of the PCM.

DIAGNOSIS

.

SYMPTOM

INSPECTION
PROCEDURE NO.

REFERENCE
PAGE

Communication with
scan tool is not
possible

Communication with all systems is
impossible

-

Group 13A,
diagnosis

P.13A-831

.

Communication with the PCM only is
impossible

-

Group 13A,
diagnosis

P.13A-834

.

Auto-cruise control
is not cancelled.

When brake pedal is depressed

1

P.17-39

When selector lever is moved to "N" range 2

P.17-39

When "CANCEL" switch is turned ON

3

P.17-40

Auto-cruise control cannot be set.

4

P.17-40

Hunting (repeated acceleration and deceleration) occurs at the
set vehicle speed.

5

P.17-42

Auto-cruise control indicator light inside combination meter does
not illuminate. (However, auto-cruise control is normal.)

6

P.17-43

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-40

Refer to GROUP 23A, Diagnostic Trouble Code Procedures

−

DTC 27: Transmission Range Switch System (Open Circuit)

P.23A-121

, DTC 28: Transmission Range Switch System

(Short Circuit)

P.23A-150

.

INSPECTION PROCEDURE 3: When the Auto-cruise Control "CANCEL" Switch is Set to ON,
Auto-cruise Control is not Cancelled.

.

COMMENT
The cause is probably an open-circuit in the output in
the circuit inside the "CANCEL" switch.

.

TROUBLESHOOTING HINTS (The most likely
causes for this case:)

• Malfunction of the auto-cruise control switch.

DIAGNOSIS

.

Replace the auto-cruise control switch. Refer to

P.17-58

,

Auto-cruise Control.

INSPECTION PROCEDURE 4: Auto-cruise Control cannot be Set.

.

COMMENT
The fail-safe function is probably cancelling
auto-cruise control. In this case, scan tool MB991958
can be used to check the trouble symptoms in each
system by checking the diagnostic trouble codes.
The scan tool can also be used to check if the cir-
cuits of each input switch are normal or not by check-
ing the input switch codes.

.

TROUBLESHOOTING HINTS (The most likely
causes for this case:)

• Malfunction of the auto-cruise control switch.

• Malfunction of the PCM.

DIAGNOSIS

.

Required Special Tools:

• MB991958: Scan tool (MUT-III sub assembly)

• MB991824: V.C.I.

• MB991827: MUT-III USB cable

• MB991911: MUT-III main harness B

• MB991223: Harness set

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-41

STEP 1. Using scan tool MB991958, read the diagnostic
trouble code.

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) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Check for auto-cruise control system diagnostic trouble

code.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC set?

YES : Refer to

P.17-15

, Diagnostic Trouble Code Chart.

NO : Go to Step 2.

AC306409AF

MB991911

MB991824

MB991827

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-42

STEP 2. Using scan tool MB991958, check data list item 04:
Cancel Switch, item 07: Transmission Range 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) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Set scan tool MB991958 to data reading mode.

Item 04 auto-cruise control system, Cancel Switch.

• When "CANCEL" switch is at the ON position, the

display on scan tool MB991958 should be "ON."

• When "CANCEL" switch is at the OFF position, the

display on scan tool MB991958 should be "OFF."

(4) Set scan tool MB991958 to data reading mode.

Item 07 auto-cruise control system, Transmission Range

Switch.

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

display on scan tool MB991958 should be "ON."

• When selector lever is at the "R" or "D" position, the

display on scan tool MB991958 should be "OFF."

(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the switch operating properly?

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.00-6

.

NO : Follow the symptom procedures below.

• Item 04:

Refer to

P.17-40

, Symptom Procedures number 3.

•

Item 07: Refer to

P.17-39

, Symptom Procedures

number 2.

INSPECTION PROCEDURE 5: Hunting (Repeated Acceleration and Deceleration) Occurs at the Set
Vehicle Speed.

.

COMMENT
The vehicle speed sensor or the throttle body is sus-
pected.

.

TROUBLESHOOTING HINTS (The most likely
causes for this case:)

• Malfunction of the vehicle speed sensor.

• Malfunction of the throttle body.

• Malfunction of the PCM.

DIAGNOSIS

.

Check for MFI system diagnostic trouble code. Refer to
GROUP 13A, Diagnostic Trouble Code Chart

P.13A-26

.

AC306409AF

MB991911

MB991824

MB991827