Mitsubishi Galant. Manual - part 367

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-38

Auto-cruise control is not can-
celled.

When brake pedal is depressed

2

P.17-46

When selector lever is moved to "N" 
range

3

P.17-53

When "CANCEL" switch is turned 
ON

4

P.17-57

Auto-cruise control cannot be set.

5

P.17-57

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

6

P.17-59

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

7

P.17-62

SYMPTOMS

INSPECTION 
PROCEDURE 
NO.

REFERENCE 
PAGE

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-39

SYMPTOM PROCEDURES

INSPECTION PROCEDURE 1: Communication With Scan Tool MB991502 is not Possible 
(Communication with the Auto-cruise Control-ECU Only is not Possible.)

AC004590

Auto-cruise Control-ECU Supply, Ground and Data Link Circuit

AB

AC004591

CONNECTOR: C-23

AB

AC004592AB

CONNECTOR: C-73

JUNCTION BLOCK
(FRONT VIEW)

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-40

CIRCUIT OPERATION
Power of the auto-cruise control-ECU is transmitted 
from the ignition switch (IG1) to the auto-cruise 
control-ECU through multi-purpose fuse 13 in the 
junction block.

TECHNICAL DESCRIPTION (COMMENT)
The cause is probably a malfunction of the auto-
cruise control-ECU power supply circuit or the auto-
cruise control-ECU ground circuit.

TROUBLESHOOTING HINTS

•

Damaged harness or connector.

•

Malfunction of the auto-cruise control-ECU.

DIAGNOSIS

Required Special Tool:

•

MB991223: Harness Set

STEP 1. Check the output circuit voltage at auto-cruise 
control-ECU connector C-52 by backprobing.
(1) Do not disconnect auto-cruise control-ECU connector C-52.
(2) Turn the ignition switch to "ON" position.
(3) Measure the voltage between terminal 6 and ground by 

backprobing.

(4) Turn the ignition switch to "LOCK" (OFF) position.

Q: Is the voltage approximately battery positive voltage?

YES : Go to Step 5.
NO :  Go to Step 2.

AC004572AB

CONNECTOR: C-52

AC004593AB

CONNECTOR: C-77

JUNCTION BLOCK
(FRONT VIEW)

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16

ACX01902AD

C-52 CONNECTOR
HARNESS SIDE VIEW

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-41

STEP 2. Check auto-cruise control-ECU connector C-52.
Q: Is the connector damaged?

YES : Repair or replace connector. 

Refer to GROUP 00E, Harness Connector Inspection 

P.00E-2

. 

Then check that the malfunction is eliminated.

NO :  Go to Step 3.

STEP 3. Check junction block connector C-73 and C-77.
Q: Is any connector damaged?

YES : Repair or replace connector. 

Refer to GROUP 00E, Harness Connector Inspection 

P.00E-2

. 

Then check that the malfunction is eliminated.

NO :  Go to Step 4.

STEP 4. Check the harness wire between ignition switch 
and auto-cruise control-ECU connector C-52.
Q: Is any harness wire between ignition switch and auto-

cruise control-ECU connector C-52 damaged?
YES : Repair the harness wire and then check that the 

malfunction is eliminated.

NO :  Check that the malfunction is eliminated. 

If the malfunction is eliminated, replace the auto-
cruise control-ECU. (Refer to 

P.17-74

.)

Then check that the malfunction is eliminated.

AC004572AB

CONNECTOR: C-52

AC004592AB

CONNECTOR: C-73

JUNCTION BLOCK
(FRONT VIEW)

AC004593AB

CONNECTOR: C-77

JUNCTION BLOCK
(FRONT VIEW)

AC004572AB

CONNECTOR: C-52