2005 MITSUBISHI 380 Workshop Manual

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-30
Q: Are the connectors and terminals in good condition?
YES : Go to Step 13.
NO : Repair the faulty connector if possible, or as
recommended, replace complete wiring harness.
(Refer to GROUP 00E, Harness Connector Inspection
P.00E-2). Install the air bag module (driver’s side).
(Refer to GROUP 52B, Air Bag Modules and Clock
Spring P.52B-237). Then go to Step 18.
STEP 13. Check the harness wire between Engine ECU
connector B-21 terminal 15 and auto-cruise control switch
connector C-302 terminal 3 for damage.
Q: Are the harness wires in good condition?
YES : Go to Step 14.
NO : Repair the damaged harness wire if possible, or
replace complete wiring harness and install the air
bag module (driver’s side). (Refer to GROUP 52B, Air
Bag Modules and Clock Spring P.52B-237). Then go
to Step 18.

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-31
STEP 14. Check the clock spring.
Refer to GROUP 52B, Air Bag Modules and Clock Spring
P.52B-244.
Q: Is the clock spring in good condition?
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). Install
the air bag module (driver’s side). (Refer to GROUP
52B, Air Bag Modules and Clock Spring P.52B-237).
Then go to Step 18.
NO : Replace the clock spring and install the air bag
module (driver’s side). (Refer to GROUP 52B, Air Bag
Modules and Clock Spring P.52B-237). Then go to
Step 18.
STEP 15. Check auto-cruise control switch connector
C-302 for loose, corroded or damaged terminals, or
terminals pushed back in the connector.
Q: Are the connector and terminals in good condition?
YES : Go to Step 16.
NO : Repair the faulty connector if possible, or as
recommended, replace complete wiring harness or
module. (Refer to GROUP 00E, Harness Connector
Inspection P.00E-2). Install the air bag module
(driver’s side). (Refer to GROUP 52B, Air Bag
Modules and Clock Spring P.52B-237). Then go to
Step 18.

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-32
STEP 16. Check the auto-cruise control switch.
(1) Remove auto-cruise control switch. (Refer to P.17-75).
(2) Measure the resistance between terminal 2 and terminal 3
when each of the "CRUISE" (MAIN), "COAST/SET",
"ACC/RES" and "CANCEL" switch is pressed.
Q: Is the resistance within specifications?
YES : Install the air bag module (driver’s side). (Refer to
GROUP 52B, Air Bag Modules and Clock Spring
P.52B-237). Then go to Step 17.
NO : Replace the auto-cruise control switch. (Refer to
P.17-75). Install the air bag module (driver’s side).
(Refer to GROUP 52B, Air Bag Modules and Clock
Spring P.52B-237). Then go to Step 18.
STEP 17. Using Diagnostic Tool MB991958, read the
diagnostic trouble code.
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) Set Diagnostic Tool MB991958 to read the diagnostic
trouble codes. (Refer to P.17-11).
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect Diagnostic Tool MB991958.
Q: Is DTC 1564 set?
YES : Replace the Engine ECU.[Refer to GROUP 13A,
Engine ECU 13A-675] . Then go to Step 18.
NO : 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). SWITCH POSITION SPECIFIED CONDITION
"CRUISE" (MAIN) switch
"OFF"Open circuit
"CRUISE" (MAIN) switch
"ON"Less than 2 ohms
"CANCEL" switch ON Approximately 100
"ACC/RES" switch ON Approximately 887
"COAST/SET" switch ON Approximately 300

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-33
STEP 18. Using Diagnostic Tool MB991958, read the
diagnostic trouble code.
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) Set Diagnostic Tool MB991958 to read the diagnostic
trouble codes. (Refer to P.17-11).
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect Diagnostic Tool MB991958.
Q: Is DTC 1564 set?
YES : Return to Step 1.
NO : The procedure is complete.

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-34
DTC 1575: Cancel Latch Signal System
.
DTC SET CONDITIONS
The Engine ECU communicates cancellation reten-
tion information between the two microprocessors.
This DTC is set when cancellation retention informa-
tion contains inconsistency.
.
TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THIS CODE TO BE
SET ARE:)
Malfunction of the Engine ECU.
Circuit drawings
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
Refer to component locations GROUP-70
DIAGNOSIS
Replace the Engine ECU.[Refer to GROUP 13A, Engine ECU
13A-675] . Then check that diagnostic trouble code P1575 is
not set.

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-35
DTC 1571: Stoplamp Switch System
.
CIRCUIT OPERATION
Battery positive voltage is supplied to the
stoplamp switch (terminal 2).
When the brake pedal is depressed, battery posi-
tive voltage is applied to the ENGINE-ECU (B-21)
(terminal 18).
.
DTC SET CONDITIONS
Check Condition
The "CRUISE" indicator lamp illuminates.
Judgement Criteria
Short in stop lamp switch circuit.
Open circuit in the brake switch circuit between
ENGINE-ECU(terminal 18) and ground.
.
TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THIS CASE:)
Malfunction of the stoplamp switch.
Damaged harness or connector.
Malfunction of the ENGINE-ECU.
Circuit drawings
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
Refer to component locations GROUP-70

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-36
DIAGNOSIS
Required Special Tools:
MB991958: Diagnostic ToolDiagnostic Tool (MUT-III Sub
Assembly)
MB991824: V.C.I.
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A
MB991223: Harness Set
MB992044: ENGINE-ECU Check Harness
STEP 1. Using Diagnostic Tool MB991958, check data list
item 74: Stoplamp Switch.
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) Set Diagnostic Tool MB991958 to data reading mode for
auto-cruise control system. (Refer to P.17-11).
Item 74, Stoplamp Switch.
When the brake pedal is depressed, the display on
Diagnostic Tool MB991958 should be "ON".
When the brake pedal is released, the display on
Diagnostic Tool MB991958 should be "OFF".
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect Diagnostic Tool MB991958.
Q: Is the switch operating properly?
YES : Go to Step 14.
NO : Go to Step 2.
STEP 2. Check the stoplamp operation.
Check the stoplamp operation.
When the brake pedal is depressed, the stoplamp will
illuminate.
When the brake pedal is released, the stoplamp does
not illuminate.
Q: Does the stoplamp illuminate (when the brake pedal is
depressed) and the stoplamp does not illuminate (when
the brake pedal is released)?
YES : Go to Step 3.
NO : Go to Step 6.

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-37
STEP 3. Measure the terminal voltage at Engine ECU
connector B-21.
(1) Disconnect all the connectors from the Engine ECU.
(2) Connect special tool MB992044 between the Engine ECU
and the body-side harness connector.
(3) Turn the ignition switch to the "ON" position.
(4) Measure the terminal voltage between special tool 94-pin
connector terminal 18 (Engine ECU connector B-21
terminal 18) and ground.
When the brake pedal is depressed, the voltage should
measure battery positive voltage (approximately 12
volts).
When the brake pedal is released, the voltage should
measure 1 volt or less.
(5) Turn the ignition switch to the "LOCK" (OFF) position.
(6) Disconnect special tool MB992044 between the Engine
ECU and the body-side harness connector.
(7) Reconnect all the connectors to the Engine ECU.
Q: Is the measured voltage battery positive voltage
(approximately 12 volts) when the brake pedal is
depressed and 1 volt or less when the brake pedal is
released?
YES : Go to Step 13.
NO : Go to Step 4.