Mitsubishi Eclipse. Manual - part 683

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-13

DIAGNOSTIC TROUBLE CODE PROCEDURES

DTC 11: Auto-cruise Vacuum Pump Drive System

AC106578AB

Auto-cruise Vacuum Pump Drive System Circuit

AC001449

CONNECTOR: A-01

RESERVE
TANK

AB

AC001451

CONNECTOR: C-20

AB

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-14

.

CIRCUIT OPERATION
This circuit activates the vacuum pump used to 
accelerate/decelerate, set, and cancel the vehicle 
speed. The auto-cruise control-ECU controls the 
control valve, release valve, and motor by turning the 
transistor in the ECU on and off.

.

DTC SET CONDITIONS
Any drive signal for the release valve, control valve 
or motor is not input to the auto-cruise control-ECU.

.

TROUBLESHOOTING HINTS
The most likely causes for this code to be set are:

• Malfunction of the auto-cruise vacuum pump.

• 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-20 (terminal numbers 7,8 and 16) 
by backprobing.
(1) Do not disconnect auto-cruise control-ECU connector C-20.
(2) Turn the ignition switch to the "ON" position and the 

auto-cruise control main switch to the "ON" position.

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

backprobing.

• Voltage should be battery positive voltage. [When decel-

erating 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 decel-

erating 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 the "LOCK" (OFF) position.
Q: Are all of the above values satisfied?

YES : Check that diagnostic trouble code 11 is not output. If 

diagnostic trouble code 11 is output, replace the 
auto-cruise control-ECU (Refer to 

P.17-92

.). Then 

check that diagnostic trouble code 11 is not.

NO :  Go to Step 2.

AC101196AB

CONNECTOR: C-06

AC101197AB

CONNECTOR: C-94

CONNECTOR 
BLOCK (RH)

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16

AC103112

C-20 CONNECTOR
HARNESS SIDE VIEW

AB

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-15

STEP 2. Check auto-cruise control-ECU connector C-20 
and intermediate connector C-94.
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 11 is not output.

NO :  Go to Step 3.

STEP 3. 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 11 is not output.

NO :  Go to Step 4.

AC001451

CONNECTOR: C-20

AB

AC101197AB

CONNECTOR: C-94

CONNECTOR 
BLOCK (RH)

AC001449

CONNECTOR: A-01

RESERVE
TANK

AB

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-16

STEP 4. 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 vac-

uum pump connector terminal 1, and the negative bat-
tery 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 vac-
uum 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 vac-
uum 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 5.
NO :  Replace the auto-cruise vacuum pump (Refer to 

P.17-92

.). Then check that diagnostic trouble code 11 

is not output.

ACX01181AB

VACUUM 
GAUGE

CONTROL
VALVE

RELEASE
VALVE