Mitsubishi 380. Manual — part 349

AUTO-CRUISE CONTROL

ENGINE AND EMISSION CONTROL

17-64

STEP 2. Using Diagnostic Tool MB991958, read the MPI
diagnostic trouble code.

CAUTION

To prevent damage to Diagnostic Tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting Diagnostic Tool
MB991958.
(1) Connect Diagnostic Tool MB991958 to the data link

connector. (Refer to

P.17-11

).

(2) Turn the ignition switch to the "ON" position.
(3) Check for MPI system diagnostic trouble code(Refer to

GROUP 13A, MPI Diagnosis

− Diagnostic Function − How

to Read and Erase Diagnostic Trouble Code

13A-6

).

(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect Diagnostic Tool MB991958.

Q: Is DTC U1108 set?

YES : . Then go to Step 4.
NO : Go to Step 3.

STEP 3. Retest the system.

Q: Does the "CRUISE" indicator lamp illuminate when the

"CRUISE" (MAIN) switch is turned "ON"?
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.00-14

).

NO : Replace the Engine ECU. [Refer to GROUP 13A,

Engine ECU

13A-675

]. Then go to Step 4.

STEP 4. Retest the system.

Q: Does the "CRUISE" indicator lamp illuminate when the

"CRUISE" (MAIN) switch is turned "ON"?
YES : The procedure is complete.
NO : Return to Step 1.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AUTO-CRUISE CONTROL

ENGINE AND EMISSION CONTROL

17-65

DATA LIST REFERENCE TABLE - Auto Cruise Control

M1172002400471

CAUTION

• When shifting the selector lever to "D" range, apply the brakes so that the vehicle does not move

forward.

• Driving tests always need two persons: one driver and one observer.

NOTE: *:After the inspection is completed, disconnect the throttle position sensor connector, and then delete
the diagnostic trouble code using use of Diagnostic Tool MB991958. (Refer to

P.17-11

).

MUT-III
Diagnostic
Tool
DISPLAY

ITEM
NO.

INSPECTION ITEM

INSPECTION REQUIREMENT

NORMAL
CONDITION

APS
SNS(MAIN)

11

Accelerator pedal
position sensor (main)

Ignition
switch:
"ON"

Accelerator pedal: Released

435

− 1,035 mV

Accelerator pedal: Gradually
depressed

Increases in
response to the
pedal depression
stroke

Accelerator pedal: Fully
depressed

4,000 mV or more

BRAKE SW

89

Stoplamp switch

Brake pedal: Depressed

ON

Brake pedal: Released

OFF

CANCEL
CODE

57

Cancel code

Ignition switch: "ON"

The cancel code,
which set when the
auto-cruise control
system was
cancelled at the
last time, is set
again.

CANCEL
SWITCH

75

Auto-cruise
control
switch

CANCEL

"CANCEL" switch: ON

ON

"CANCEL" switch: OFF

OFF

CLUTCH SW 78

Transmission inhibitor
switch

Transmission inhibitor switch: "P" or
"N"

ON

Transmission inhibitor switch: Other
than above

OFF

CRUISE

81

Auto-cruise control
system operation

Auto-cruise control system: active

ON

Auto-cruise control system: Inactive

OFF

MAIN SW

86

Auto-cruise
control
switch

CRUISE
(MAIN)

"CRUISE" (MAIN) switch: "ON"

ON

"CRUISE" (MAIN) switch: "OFF"

OFF

RESUME
SWITCH

91

Auto-cruise
control
switch

ACC/RES "ACC/RES" switch: ON

ON

"ACC/RES" switch: OFF

OFF

SET SWITCH 92

Auto-cruise
control
switch

COAST/S
ET

"COAST/SET" switch: ON

ON

"COAST/SET" switch: OFF

OFF

STOPLIGHT
SW

74

Stoplamp switch

Brake pedal: Depressed

ON

Brake pedal: Released

OFF

AUTO-CRUISE CONTROL

ENGINE AND EMISSION CONTROL

17-66

WARNING

If the air intake duct is removed from the throttle body take great care to keep fingers away
from the throttle plate. The drive motor has very high torque and is capable of random move-
ment at any time. Do not under any circumstances activate the throttle plate by hand.
When removing the throttle body from the intake manifold disconnect the wiring first. During
replacement connect the wiring last.
Do not activate the throttle body using a DC suppy to test the motor,as permanent damage to
the throttle body will result.

TP
SNSR(MAIN)

13

Throttle position sensor
(main)*

(1) Accelerator pedal:
Released
(2) Accelerator pedal:
Depressed

(1) Throttle
valve fully
closed

1035

− 1250 mV

(2) Throttle
valve fully
open

4,000 mV or more

A/C switch: "OFF" to "ON"

Voltage rises

Selector lever: "N" to "D"

Voltage rises

VSS

04

Vehicle speed signal

Road test the vehicle

The speedometer
and Diagnostic
Tool MB991958
display the same
value.

MUT-III
Diagnostic
Tool
DISPLAY

ITEM
NO.

INSPECTION ITEM

INSPECTION REQUIREMENT

NORMAL
CONDITION

AUTO-CRUISE CONTROL

ENGINE AND EMISSION CONTROL

17-67

ENGINE ECU TERMINAL VOLTAGE REFERENCE CHART FOR AUTO-CRUISE
CONTROL SYSTEM OPERATION

M1172004800055

1. Disconnect the Engine ECU connectors B-20,

B-21, and connect special tool MB992044
(ENGINE ECU check harness) in between.

2. Measure the voltages between the check

connector terminals of special tool MB992044 and
ground connector B-21 terminals 4 or 6.

16DB403A

SPECIAL TOOL- ENGINE ECU CHECK HARNESS (MB992044) CONNECTOR:

94-PIN
CONNECTOR
(ENGINE ECU CONNECTOR
B-21)

60-PIN
CONNECTOR
(ENGINE ECU CONNECTOR
B-20)

TERMINAL
NO.

CHECK ITEM

CHECK CONDITION

NORMAL
CONDITION

18 (B-21)

Stoplamp switch

Ignition
switch:
"ON"

Depress the brake pedal.

Battery positive
voltage

Release the brake pedal.

1V or less

14 (B-21)

Auto-cruise control
switch power supply

Ignition
switch:
"ON"

All switches: OFF

4.7

− 5.0 V

"CRUISE" (MAIN) switch: "ON"

0

− 0.3 V

"COAST/SET" switch: ON

2.0

− 2.8 V

"ACC/RES" switch: ON

3.3

− 4.1 V

"CANCEL" switch: ON

0.8

− 1.5 V

76 (B-21)

Accelerator pedal
position sensor (sub)
power supply

Ignition switch: "ON"

4.9

− 5.1 V

59 (B-21)

Accelerator pedal
position sensor
(main)

Ignition
switch:
"ON"

Release the accelerator pedal

0.435

− 1.035 V

Depress the accelerator pedal.

4.0 V or more

81 (B-21)

Accelerator pedal
position sensor (sub)

Ignition
switch:
"ON"

Release the accelerator pedal

0.435

− 1.035 V

Depress the accelerator pedal.

4.0 V or more

75 (B-21)

Accelerator pedal
position sensor
(main) power supply

Ignition switch: "ON"

4.9

− 5.1 V

21 (B-21)

Brake switch

Ignition
switch:
"ON"

Depress the brake pedal.

1V or less

Release the brake pedal.

1V or less

9 (B-20)

Transmission inhibitor
switch: "P" and "N"
Crank switch signal

Ignition
switch:
"ON"

Transmission inhibitor switch: "P" or
"N" Crank switch signal

Battery positive
voltage

Transmission inhibitor switch: Other
than above

1V or less