DTC 15: Auto-cruise Control Switch System: Diagnosis

Required Special Tools:

MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A
MB991223: Harness Set
MB992006: Extra Fine Probe
MB992110: Power Plant ECU Check Harness

STEP 1. Using scan tool MB991958, check the data list item 86: Main switch, item 92: Set switch, item 91: Resume switch and item 75: Cancel switch.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958 to the data link connector (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III) ).
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to data reading mode for auto-cruise control system (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III) ).
  - Item 86: Main switch.
    - When "ON/OFF" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
    - When "ON/OFF" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
  - Item 92: Set switch.
    - When "COAST/SET" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
    - When "COAST/SET" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
      
      Fig 1: Connecting Scan Tool MB991824 To Data Link Connector
      Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  - Item 91: Resume switch.
    - When "ACC/RES" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
    - When "ACC/RES" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
  - Item 75: Cancel switch.
    - When "CANCEL" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
    - When "CANCEL" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool MB991958.
Q: Is the switch operating properly?

YES: It can be assumed that this malfunction is intermittent (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ).

NO: Go to Step 2.
STEP 2. Measure the power supply voltage at auto-cruise control switch connector C-201 by backprobing.
1. Remove the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ).
2. Remove the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ).
3. Connect the negative (-) battery cable.
4. Do not disconnect auto-cruise control switch connector C-201.
5. Turn the ignition switch to the "ON" position.
6. All auto-cruise control switch to the "OFF" position.
7. Measure the power supply voltage between auto-cruise control switch connector C-201 terminal 3 and ground by backprobing.
8. Turn the ignition switch to the "LOCK" (OFF) position.
  
  Fig 2: Measuring Voltage Between Auto-Cruise Control Switch Connector C-201 Terminal 3 And Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
Q: Is the measured voltage between 4.7 and 5.0 volts?

YES: Go to STEP 9.

NO: Go to Step 3.
STEP 3. Measure the power supply voltage at ECM connector B-11.
1. Disconnect all the connectors from the ECM.
2. Connect special tool MB992110 between the ECM and the body-side harness connector.
3. Turn the ignition switch to the "ON" position.
4. All auto-cruise control switch to the "OFF" position.
  
  Fig 3: Connecting Special Tool MB992110 Between ECM And Body-Side Harness Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  
  Fig 4: Identifying Special Tool 48-Pin Connector - Component Side
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
5. Measure the power supply voltage between special tool 48-pin connector terminal 37 (ECM connector B-11 terminal 107) and ground.
6. Turn the ignition switch to the "LOCK" (OFF) position.
7. Disconnect special tool MB992110 between the ECM and the body-side harness connector.
8. Reconnect all the connectors to the ECM.
Q: Is the measured voltage between 4.7 and 5.0 volts?

YES: Go to STEP 6.

NO: Go to Step 4.
STEP 4. Check ECM connector B-11 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 5.

NO: Repair or replace the faulty connector (Refer to HARNESS CONNECTOR INSPECTION ). Install the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.
STEP 5. Check the harness for short circuit to ground between the ECM connector B-11 terminal 107 and the autocruise control switch connector C-201 terminal 3.
1. Disconnect ECM connector B-11 and measure at the harness connector side.
2. Turn the ignition switch to the "LOCK" (OFF) position.
3. Measure the continuity between ECM connector B-11 terminal 107 and ground.
4. Reconnect ECM connector B-11.
Q: Is the measured continuity open circuit?

YES: Install the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 17.

NO: Go to Step 6.

Fig 5: Measuring Continuity Between ECM Connector B-11 Terminal 107 And Ground
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 6. Check intermediate connector C-34, auto-cruise control switch connector C-201 and clock spring connectors C-202 and C-204 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?

YES: Go to Step 7.

NO: Repair or replace the faulty connector (Refer to HARNESS CONNECTOR INSPECTION ). Install the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.
STEP 7. Check the harness wire between ECM connector B-11 terminal 107 and auto-cruise control switch connector C-201 terminal 3 for damage.
Q: Are the harness wires in good condition?

YES: Go to Step 8.

NO: Repair the damaged harness wire. Install the autocruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.
STEP 8. Check the clock spring.
Refer to AIR BAG MODULES AND CLOCK SPRING .

Q: Is the clock spring in good condition?

YES: It can be assumed that this malfunction is intermittent (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ). Install the autocruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.

NO: Replace the clock spring (Refer to AIR BAG MODULES AND CLOCK SPRING ). Install the autocruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.
STEP 9. Measure the ground voltage at auto-cruise control switch connector C-201 by backprobing.
1. Do not disconnect auto-cruise control switch connector C-201.
2. Turn the ignition switch to the "ON" position.
3. Turn the "ON/OFF" switch to the "ON" position.
4. Measure the ground voltage between auto-cruise control switch connector C-201 terminal 2 and ground by backprobing.
5. Turn the "ON/OFF" switch to the "OFF" position.
6. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage 0.5 volt or less?

YES: Go to STEP 15.

NO: Go to Step 10.

Fig 6: Measuring Voltage Between Auto-Cruise Control Switch Connector C-201 Terminal 2 And Ground
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 10. Measure the ground voltage at ECM connector B-11.
1. Disconnect all the connectors from the ECM.
2. Connect special tool MB992110 between the ECM and the body-side harness connector.
3. Turn the ignition switch to the "ON" position.
4. Turn the "ON/OFF" switch to the "ON" position.
  
  Fig 7: Connecting Special Tool MB992110 Between ECM And Body-Side Harness Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  
  Fig 8: Measuring Ground Voltage Between Special Tool 48-Pin Connector Terminal 25 And Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
5. Measure the ground voltage between special tool 48-pin connector terminal 25 (ECM connector B-11 terminal 95) and ground.
6. Turn the "ON/OFF" switch to the "OFF" position.
7. Turn the ignition switch to the "LOCK" (OFF) position.
8. Disconnect special tool MB992110 between the ECM and the body-side harness connector.
9. Reconnect all the connectors to the ECM.
Q: Is the measured voltage 0.5 volt or less?

YES: Go to STEP 12.

NO: Go to Step 11.
STEP 11. Check ECM connector B-11 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connector and terminals in good condition?

YES: Install the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 17.

NO: Repair or replace the faulty connector (Refer to HARNESS CONNECTOR INSPECTION ). Install the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.
STEP 12. Check ECM connector B-11, intermediate connector C-34, auto-cruise control switch connector C-201 and clock spring connectors C-202 and C-204 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?

YES: Go to Step 13.

NO: Repair or replace the faulty connector (Refer to HARNESS CONNECTOR INSPECTION ). Install the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.
STEP 13. Check the harness wire between ECM connector B-11 terminal 95 and auto-cruise control switch connector C-201 terminal 2 for damage.
Q: Are the harness wires in good condition?

YES: Go to Step 14.

NO: Repair the damaged harness wire. Install the autocruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.
STEP 14. Check the clock spring.
Refer to AIR BAG MODULES AND CLOCK SPRING .

Q: Is the clock spring in good condition?

YES: It can be assumed that this malfunction is intermittent (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ). Install the autocruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.

NO: Replace the clock spring (Refer to AIR BAG MODULES AND CLOCK SPRING ). Install the autocruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.
STEP 15. Check auto-cruise control switch connector C-201 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 or replace the faulty connector (Refer to HARNESS CONNECTOR INSPECTION ). Install the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.

STEP 16. Check the auto-cruise control switch.

Remove the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ).

Measure the resistance between terminal 2 and terminal 3 when each of the "ON/OFF", "COAST/SET", "ACC/RES" and "CANCEL" switch is pressed.

SWITCH POSITION CONDITION CHART

Switch position	Specified condition
"ON/OFF" switch "OFF"	Open circuit
"ON/OFF" switch "ON"	Continuity (less than 2 ohms)
"CANCEL" switch ON	202.5 - 208 Ω
"COAST/SET" switch ON	610.5 - 624.5 Ω
"ACC/RES" switch ON	1838 - 1877 Ω

Q: Is the resistance within specifications?

YES: Install the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ) and the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to Step 17.

NO: Replace the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ). Install the driver's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to STEP 18.

Fig 9: Identifying Auto-Cruise Control Switch

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

STEP 17. Using scan tool MB991958, check the data list item 86: Main switch, item 92: Set switch, item 91: Resume switch and item 75: Cancel switch.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958 to the data link connector (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III) ).
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to data reading mode for auto-cruise control system (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III) ).
  - Item 86: Main switch.
    - When "ON/OFF" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
    - When "ON/OFF" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
  - Item 92: Set switch.
    - When "COAST/SET" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
    - When "COAST/SET" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
  - Item 91: Resume switch.
    - When "ACC/RES" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
    - When "ACC/RES" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
  - Item 75: Cancel switch.
    - When "CANCEL" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
    - When "CANCEL" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool MB991958.
Q: Is the switch operating properly?

YES: It can be assumed that this malfunction is intermittent (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ).

NO: Replace the ECM. When the ECM is replaced, register the encrypted code (Refer to ID CODE REGISTRATION NECESSITY JUDGMENT TABLE ). Then go to Step 18.
STEP 18. Read the diagnostic trouble code.
1. Erase diagnostic trouble code. (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III) ).
2. Turn the ignition switch to the "ON" position.
3. Turn the "ON/OFF" switch to the "ON" position (turn on the "CRUISE" indicator lamp).
4. Read the diagnostic trouble codes (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III) ).
Q: Is DTC 15 set?

YES: Return to STEP 1.

NO: The procedure is complete.