DTC15: Auto-cruise Control Switch System: Diagnosis

Required Special Tools:

MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: MUT-III USB Cable
- MB991910: MUT-III Main Harness A
MB991223: Harness Set
MB991923: Power Plant ECU Check Harness

STEP 1. Using scan tool MB991958, check data list item 02: Set 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 DIAGNOSTIC FUNCTION ).
  
  Fig 1: Connecting Scan Tool To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
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 DIAGNOSTIC FUNCTION ).
  - Item 02: 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".
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool MB991958.
Q: Is the switch operating properly?
1. YES : Go to Step 2.
2. NO : Go to Step 3.
STEP 2. Using scan tool MB991958, check data list item 03: Resume 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 DIAGNOSTIC FUNCTION ).
  
  Fig 2: Connecting Scan Tool To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
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 DIAGNOSTIC FUNCTION ).
  - Item 03: 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".
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool MB991958.
Q: Is the switch operating properly?
1. YES : Go to Step 17.
2. NO : Go to Step 3.
STEP 3. Measure the power supply voltage at auto-cruise control switch connector C-302 by backprobing.
1. Remove the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ).
2. Connect the negative (-) battery cable.
3. Do not disconnect auto-cruise control switch connector C-302.
  
  Fig 3: Identifying Switch Connector C-302
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Turn the ignition switch to the "ON" position and the "CRUISE" (MAIN) switch to the "OFF" position.
5. Measure the power supply voltage between auto-cruise control switch connector C-302 terminal 2 and ground by backprobing.
  
  Fig 4: Measuring Power Supply Voltage Between Auto-Cruise Control Switch Connector C-302 Terminal 2 And Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
6. Turn the ignition switch to the "OFF" position.
Q: Is the measured voltage between 4.7 and 5.3 volts?
1. YES : Go to Step 10.
2. NO : Go to Step 4.
STEP 4. Measure the power supply voltage at PCM connector B-18.
1. Disconnect all the connectors from the PCM.
  
  Fig 5: Locating PCM Connector B-18
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  
  Fig 6: Identifying PCM Connector B-18
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. Connect special tool MB991923 (check harness) between the PCM and the body-side harness connector.
3. Turn the ignition switch to the "ON" position and the "CRUISE" (MAIN) switch to the "OFF" position.
4. Measure the power supply voltage between special tool 18-pin connector terminal 12 (PCM connector B-18 terminal 12) and ground.
  
  Fig 7: Measuring Power Supply Voltage Between Special Tool 18-Pin Connector Terminal 12Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
5. Turn the ignition switch to the "OFF" position.
Q: Is the measured voltage between 4.7 and 5.3 volts?
1. YES : Go to Step 5.
2. NO : Go to Step 8.
STEP 5. Check PCM connector B-18, intermediate connector C-31, auto-cruise control switch connector C-302 and clock spring connectors C-303 and C-306 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Fig 8: Identifying B-18 Intermediate Connector
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Fig 9: Identifying C-31 Intermediate Connector
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Fig 10: Identifying C-302, C-303, C-306 Harness Connector
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Are the connectors and terminals in good condition?
1. YES : Go to Step 6.
2. NO : Repair or replace the faulty connector, (refer to HARNESS CONNECTOR INSPECTION , and install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.
STEP 6. Check the harness wire between PCM connector B-18 terminal 12 and auto-cruise control switch connector C-302 terminal 2 for damage.

Fig 11: Identifying PCM Connector B-18
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Fig 12: Identifying Auto-Cruise Control Switch Connector C-302
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Is the harness wire in good condition?
1. YES : Go to Step 7.
2. NO : Repair the damaged harness wire, and install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.
STEP 7. Check the clock spring.
Refer to AIR BAG MODULE AND CLOCK SPRING .

Q: Is the clock spring in good condition?
1. YES : It can be assumed that this malfunction is intermittent. (Refer to HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS - HOW TO COPE WITH INTERMITTENT MALFUNCTION ). Install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.
2. NO : Replace the clock spring and install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.
STEP 8. Check PCM connector B-18 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Fig 13: Identifying PCM Connector B-18
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Are the connector and terminals in good condition?
1. YES : Go to Step 9.
2. NO : Repair or replace the faulty connector, (Refer to HARNESS CONNECTOR INSPECTION , and install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.
STEP 9. Check the harness for short circuit to ground between the PCM connector B-18 terminal 12 and the auto-cruise control switch connector C-302 terminal 2.
1. Disconnect PCM connector B-18 and measure at the harness connector side.
  
  Fig 14: Identifying B-18 PCM Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. Turn the ignition switch to the "ON" position and the "CRUISE" (MAIN) switch to the "OFF" position.
3. Measure the continuity between PCM connector B-18 terminal 12 and ground.
  
  Fig 15: Measuring Continuity Between PCM Connector B-18 Terminal 12 And Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Turn the ignition switch to the "OFF" position.
Q: Is the measured continuity open circuit?
1. YES : Install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 17.
2. NO : Repair or replace the harness wire, and install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.
STEP 10. Measure the ground voltage at auto-cruise control switch connector C-302 by backprobing.
1. Do not disconnect auto-cruise control switch connector C-302.
  
  Fig 16: Identifying C-302 Harness Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. Turn the ignition switch to the "ON" position and the "CRUISE" (MAIN) switch to the "ON" position.
3. Measure the ground voltage between auto-cruise control switch connector C-302 terminal 3 and ground by backprobing.
  
  Fig 17: Measuring Ground Voltage Between Auto-Cruise Control Switch Connector C-302 Terminal 3 Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Turn the "CRUISE" (MAIN) switch to the "OFF" position and the ignition switch to the "OFF" position.
Q: Is the measured voltage 0.5 volt or less?
1. YES : Go to Step 11.
2. NO : Go to Step 16.
STEP 11. Measure the power supply voltage at PCM connector B-19.
1. Disconnect all the connectors from the PCM.
  
  Fig 18: Locating PCM Connector B-19
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  
  Fig 19: Identifying PCM B-19 Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. Connect special tool MB991923 (check harness) between the PCM and the body-side harness connector.
3. Turn the ignition switch to the "ON" position and the "CRUISE" (MAIN) switch to the "ON" position.
4. Measure the ground voltage between special tool 23-pin connector (without red tape) terminal 28 (PCM connector B-19 terminal 28) and ground.
  
  Fig 20: Measuring Ground Voltage Between Special Tool 23-Pin Connector Terminal 28 Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
5. Turn the "CRUISE" (MAIN) switch to the "OFF" position the ignition switch to the "OFF" position.
Q: Is the measured voltage 0.5 volt or less?
1. YES : Go to Step 12.
2. NO : Go to Step 15.
STEP 12. Check PCM connector B-19, intermediate connector C-31, auto-cruise control switch connector C-302 and clock spring connectors C-303 and C-306 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Fig 21: Identifying PCM Connector B-19
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Fig 22: Identifying C-31 Harness Connector
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Fig 23: Identifying C-302, C-306, C-306 Harness Connector
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Are the connectors and terminals in good condition?
1. YES : Go to Step 13.
2. NO : Repair or replace the faulty connector, (Refer to HARNESS CONNECTOR INSPECTION ) and install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.
STEP 13. Check the harness wire between PCM connector B-19 terminal 28 and auto-cruise control switch connector C-302 terminal 3 for damage.

Fig 24: Identifying PCM Connector B-19
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Fig 25: Identifying C-302, C-306, C-306 Harness Connector
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Is the harness wire in good condition?
1. YES : Go to Step 14.
2. NO : Repair the damaged harness wire, and install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.
STEP 14. Check the clock spring.
Refer to AIR BAG MODULE AND CLOCK SPRING .

Q: Is the clock spring in good condition?
1. YES : It can be assumed that this malfunction is intermittent. (Refer to HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS - HOW TO COPE WITH INTERMITTENT MALFUNCTION ). Install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.
2. NO : Replace the clock spring and install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.
STEP 15. Check PCM connector B-19 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Fig 26: Identifying PCM Connector B-19
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Are the connector and terminals in good condition?
1. YES : Install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 17.
2. NO : Repair or replace the faulty connector, refer to HARNESS CONNECTOR INSPECTION and install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.

STEP 16. Check the auto-cruise control switch.

Remove auto-cruise control switch. (Refer to REMOVAL AND INSTALLATION ).

Measure the resistance between terminal 2 and terminal 3 when each of the "CRUISE" (MAIN), "COAST/SET", "ACC/RES" and "CANCEL" switch is pressed.

Fig 27: Measuring Resistance Between Terminal 2 And Terminal 3

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

RESISTANCE SPECIFIED CONDITION

SWITCH POSITION	SPECIFIED CONDITION
"CRUISE" (MAIN) switch "OFF"	Open circuit
"CRUISE" (MAIN) switch "ON"	Less than 2 ohms
"CANCEL" switch ON	Approximately 100 Ω
"ACC/RES" switch ON	Approximately 887 Ω
"COAST/SET" switch ON	Approximately 300 Ω

Q: Is the resistance within specifications?

YES : Install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 17.
NO : Replace the auto-cruise control switch, (Refer to REMOVAL AND INSTALLATION ), and install the air bag module (driver's side). (Refer to AIR BAG MODULE AND CLOCK SPRING ). Then go to Step 18.

STEP 17. Using scan tool MB991958, read the diagnostic trouble code.
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 DIAGNOSTIC FUNCTION ).
  
  Fig 28: Connecting Scan Tool To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to read the diagnostic trouble codes. (Refer to DIAGNOSTIC FUNCTION ).
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool MB991958.
Q: Is DTC 15 set?
1. YES : Replace the PCM. [Refer to POWER CONTROL MODULE (PCM) ]. Then go to Step 18.
2. NO : It can be assumed that this malfunction is intermittent. (Refer to HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS - HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
STEP 18. Using scan tool MB991958, read the diagnostic trouble code.
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 DIAGNOSTIC FUNCTION ).
  
  Fig 29: Connecting Scan Tool To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to read the diagnostic trouble codes. (Refer to DIAGNOSTIC FUNCTION ).
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool MB991958.

Q: Is DTC 15 set?

YES : Return to Step 1.
NO : The procedure is complete.