Mitsubishi Galant. Manual — part 363

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-22

STEP 5. Check the stoplight switch.
(1) Disconnect stoplight switch connector C-03.
(2) Connect an ohmmeter to the stoplight switch between

terminals 3 and 4, and check whether there is continuity
when the plunger of the stoplight switch is pushed in and an
open circuit when it is released.

(3) The stoplight switch is in good condition if the circuit is open

when the plunger is pushed in to a depth of within 4 mm
(0.2 inch) from the outer case edge surface, and if there is
continuity when it is released.

Q: Is the circuit is open?

YES : Replace the stoplight switch.

Refer to GROUP 35A, Brake Pedal

P.35A-30

.

Then check that a diagnostic trouble code 14 is not
output.

NO : Check that diagnostic trouble code 14 is not output.

If diagnostic trouble code 14 is output, replace the
auto-cruise control-ECU. (Refer to

P.17-74

.)

Then check that diagnostic trouble code 14 is not
output.

STEP 6. Check the output circuit voltage at auto-cruise
control vacuum pump connector A-01 by backprobing.
(1) Do not disconnect auto-cruise control vacuum pump

connector A-01.

(2) Turn the ignition switch to "ON" position and the auto-cruise

control main switch to "ON" position.

(3) Measure the voltage between terminal 1 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 8.
NO : Go to Step 7.

1

2

3

4

ACX01917

STOPLIGHT SWITCH
CONNECTOR: C-03

AC

AC001463

CONTINUITY

NO
CONTINUITY

4 mm (0.2 in)

AB

1

2

3

4

ACX01908AC

A-01 CONNECTOR
HARNESS SIDE VIEW

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-23

STEP 7. Check auto-cruise control vacuum pump
connector A-01 and intermediate connector C-05.
Q: Is any connector damaged?

YES : Repair or replace connector.

Refer to GROUP 00E, Harness Connector Inspection

P.00E-2

.

Then check that diagnostic trouble code 14 is not
output.

NO : Check the harness wire between stoplight switch

connector C-03 and auto-cruise control vacuum pump
connector A-01 for open circuit or damage.
Then repair if necessary.
Then check that diagnostic trouble code 14 is not
output.

STEP 8. 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 and the auto-cruise

control main switch to "ON" position.

(3) Measure the voltage between terminal 7 and ground by

backprobing.

•

Voltage should be battery positive voltage.
[When decelerating with the "SET" switch while driving
at constant speed (Release valve open).]

(4) Measure the voltage between terminal 8 and ground by

backprobing.

•

Voltage should be battery positive voltage.
[When decelerating with the "SET" switch while driving
at constant speed. (Control valve open).]

(5) Measure the voltage between terminal 16 and ground by

backprobing.

•

Voltage should be battery positive voltage.
(When the motor is stopped during a constant road
speed.)

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

Q: Are all of the above values satisfied?

YES : Check that diagnostic trouble code 14 is not output.

If diagnostic trouble code 14 is output, replace the
auto-cruise control-ECU. (Refer to

P.17-74

.)

Then check that diagnostic trouble code 14 is not.

NO : Go to Step 9.

AC001449

CONNECTOR: A-01

RESERVE
TANK

AB

AC004571

CONNECTOR: C-05

COMBINATION METER

AB

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16

ACX01897

C-52 CONNECTOR
HARNESS SIDE VIEW

AE

AUTO-CRUISE CONTROL

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ENGINE AND EMISSION CONTROL

17-24

STEP 9. Check auto-cruise control-ECU connector C-52
and intermediate connector C-12.
Q: Is the connector damaged?

YES : Repair or replace connector.

Refer to GROUP 00E, Harness Connector Inspection

P.00E-2

.

Then check that diagnostic trouble code 14 is not
output.

NO : Go to Step 10.

STEP 10. Check auto-cruise control vacuum pump
connector A-01.
Q: Is the connector damaged?

YES : Repair or replace connector.

Refer to GROUP 00E, Harness Connector Inspection

P.00E-2

.

Then check that diagnostic trouble code 14 is not
output.

NO : Go to Step 11.

AC004572AB

CONNECTOR: C-52

AC004573AC

GLOVE BOX

CONNECTOR: C-12

AC001449

CONNECTOR: A-01

RESERVE
TANK

AB

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-25

STEP 11. 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.
(3) Check the auto-cruise vacuum pump and valves according

to the following procedure:

•

Connect the positive battery terminal to auto-cruise
vacuum pump connector terminal 1, and the negative
battery terminal to terminals 2, 3, and 4.
The vacuum gauge should read 27 kPa (8.0 in Hg) or
more.

•

The vacuum should be maintained when terminal 4 is
disconnected from the negative battery terminal while
terminals 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 terminal 4 is
disconnected from the negative battery terminal while
terminals 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 12.
No : Replace the auto-cruise vacuum pump. (Refer to

P.17-74

.)

Then check that diagnostic trouble code 14 is not
output.

ACX01181AB

VACUUM
GAUGE

CONTROL
VALVE

RELEASE
VALVE