DIAGNOSTIC ITEM 4: Diagnose shorts in the ground to CAN-C bus line: Diagnosis

Required Special Tools:

MB991223: Harness Set
MB992006: Extra Fine Probe
MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A
MB991997: ASC Check Harness
MB992110: Power Plant ECU Check Harness

STEP 1. Check the wiring harness between joint connector (CAN2) C-05 and steering wheel sensor connector C-211 for a short to ground. Measure the resistance at joint connector (CAN2) C-05.
CAUTION: Disconnect the negative battery terminal. For details refer to SERVICE PRECAUTIONS .

CAUTION: A digital multimeter should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: The test wiring harness should be used. For details refer to SERVICE PRECAUTIONS .
1. Disconnect joint connector (CAN2), and measure the resistance at the wiring harness side of joint connector (CAN2).
2. Measure the resistance between joint connector (CAN2) terminal 7 and body ground.
  OK: 1 kilo ohm or more
  
  Fig 1: Measuring Resistance Between Joint Connector (CAN2) Terminal 7 And Body Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Measure the resistance between joint connector (CAN2) terminal 20 and body ground.
  OK: 1 kilo ohm or more
  
  Q: Do all the resistances measure 1 kilo ohm or more?
  1. YES <except RALLIART>: Go to Step 3.
  2. YES <RALLIART>: Go to Step 2.
  3. NO: Go to Step 11.
    
    Fig 2: Measurinh Resistance Between Joint Connector (CAN2) Terminal 20 And Body Ground
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 2. Check the wiring harness between joint connector (CAN2) C-05 and AWC-ECU connector C-51 for a short to ground. Measure the resistance at joint connector (CAN2) C-05.
CAUTION: Disconnect the negative battery terminal. For details refer to SERVICE PRECAUTIONS .

CAUTION: A digital multimeter should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: The test wiring harness should be used. For details refer to SERVICE PRECAUTIONS .
1. Disconnect joint connector (CAN2), and measure the resistance at the wiring harness side of joint connector (CAN2).
2. Measure the resistance between joint connector (CAN2) terminal 4 and body ground.
  OK: 1 kilo ohm or more
  
  Fig 3: Measuring Resistance Between Joint Connector (CAN2) Terminal 4 And Body Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Measure the resistance between joint connector (CAN2) terminal 15 and body ground.
  OK: 1 kilo ohm or more
  
  Q: Do all the resistances measure 1 kilo ohm or more?
  1. YES: Go to Step 3.
  2. NO: Go to Step 12.
    
    Fig 4: Measuring Resistance Between Joint Connector (CAN2) Terminal 15 And Body Ground
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 3. Check the wiring harness between joint connector (CAN2) C-05 and ETACS-ECU connector C-301 for a short to ground. Measure the resistance at joint connector (CAN2) C-05.
CAUTION: Disconnect the negative battery terminal. For details refer to SERVICE PRECAUTIONS .

CAUTION: A digital multimeter should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: The test wiring harness should be used. For details refer to SERVICE PRECAUTIONS .
1. Disconnect joint connector (CAN2), and measure the resistance at the wiring harness side of joint connector (CAN2).
2. Measure the resistance between joint connector (CAN2) terminal 6 and body ground.
  OK: 1 kilo ohm or more
  
  Fig 5: Measuring Resistance Between Joint Connector (CAN2) Terminal 6 And Body Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Measure the resistance between joint connector (CAN2) terminal 19 and body ground.
  OK: 1 kilo ohm or more
  
  Q: Do all the resistances measure 1 kilo ohm or more?
  1. YES: Go to Step 4.
  2. NO: Go to Step 13.
    
    Fig 6: Measuring Resistance Between Joint Connector (CAN2) Terminal 19 And Body Ground
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 4. Check the wiring harness between joint connector (CAN3) C-124 and ASC-ECU connector A-51 for a short to ground. Measure the resistance at joint connector (CAN3) C-124.
CAUTION: Disconnect the negative battery terminal. For details refer to SERVICE PRECAUTIONS .

CAUTION: A digital multimeter should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: The test wiring harness should be used. For details refer to SERVICE PRECAUTIONS .
1. Disconnect joint connector (CAN3), and measure the resistance at the wiring harness side of joint connector (CAN3).
2. Measure the resistance between joint connector (CAN3) terminal 6 and body ground.
  OK: 1 kilo ohm or more
  
  Fig 7: Measuring Resistance Between Joint Connector (CAN3) Terminal 6 And Body Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Measure the resistance between joint connector (CAN3) terminal 19 and body ground.
  OK: 1 kilo ohm or more
  
  Q: Do all the resistances measure 1 kilo ohm or more?
  1. YES <except RALLIART>: Go to Step 5.
  2. YES <RALLIART>: Go to Step 7.
  3. NO: Go to Step 14.
    
    Fig 8: Measuring Resistance Between Joint Connector (CAN3) Terminal 19 And Body Ground
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 5. Check the wiring harness between joint connector (CAN3) C-124 and TCM connector C-41 for a short to ground. Measure the resistance at joint connector (CAN3) C-124.
CAUTION: Disconnect the negative battery terminal. For details refer to SERVICE PRECAUTIONS .

CAUTION: A digital multimeter should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: The test wiring harness should be used. For details refer to SERVICE PRECAUTIONS .
1. Disconnect joint connector (CAN3), and measure the resistance at the wiring harness side of joint connector (CAN3).
2. Measure the resistance between joint connector (CAN3) terminal 7 and body ground.
  OK: 1 kilo ohm or more
  
  Fig 9: Measuring Resistance Between Joint Connector (CAN3) Terminal 7 And Body Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Measure the resistance between joint connector (CAN3) terminal 20 and body ground.
  OK: 1 kilo ohm or more
  
  Q: Do all the resistances measure 1 kilo ohm or more?
  1. YES: Go to Step 6.
  2. NO: Go to Step 15.
    
    Fig 10: Measuring Resistance Between Joint Connector (CAN3) Terminal 20 And Body Ground
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 6. Check the wiring harness between joint connector (CAN3) C-124 and ECM connector B-109 <except RALLIART> for a short to ground. Measure the resistance at joint connector (CAN3) C-124.
CAUTION: Disconnect the negative battery terminal. For details refer to SERVICE PRECAUTIONS .

CAUTION: A digital multimeter should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: The test wiring harness should be used. For details refer to SERVICE PRECAUTIONS .
1. Disconnect joint connector (CAN3), and measure the resistance at the wiring harness side of joint connector (CAN3).
2. Measure the resistance between joint connector (CAN3) terminal 4 and body ground.
  OK: 1 kilo ohm or more
  
  Fig 11: Measuring Resistance Between Joint Connector (CAN3) Terminal 4 And Body Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Measure the resistance between joint connector (CAN3) terminal 15 and body ground.
  OK: 1 kilo ohm or more
  
  Q: Do all the resistances measure 1 kilo ohm or more?
  1. YES: Check intermediate connector C-128, and repair if necessary. If the intermediate connector is in good condition, repair the wiring harness between joint connector (CAN2) C-05 and joint connector (CAN3) C-124.
  2. NO: Go to Step 16.
    
    Fig 12: Measuring Resistance Between Joint Connector (CAN3) Terminal 15 And Body Ground
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 7. Check the wiring harness between joint connector (CAN3) C-124 and shift lever connector C-49 for a short to ground. Measure the resistance at joint connector (CAN3) C-124.
CAUTION: Disconnect the negative battery terminal. For details refer to SERVICE PRECAUTIONS .

CAUTION: A digital multimeter should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: The test wiring harness should be used. For details refer to SERVICE PRECAUTIONS .
1. Disconnect joint connector (CAN3), and measure the resistance at the wiring harness side of joint connector (CAN3).
2. Measure the resistance between joint connector (CAN3) terminal 7 and body ground.
  OK: 1 kilo ohm or more
  
  Fig 13: Measuring Resistance Between Joint Connector (CAN3) Terminal 7 And Body Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Measure the resistance between joint connector (CAN3) terminal 20 and body ground.
  OK: 1 kilo ohm or more
  
  Q: Do all the resistances measure 1 kilo ohm or more?
  1. YES: Go to Step 8.
  2. NO: Go to Step 17.
    
    Fig 14: Measuring Resistance Between Joint Connector (CAN3) Terminal 20 And Body Ground
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 8. Check the wiring harness between joint connector (CAN4) A-55 and shift lever connector B-109 <RALLIART> for a short to ground. Measure the resistance at joint connector (CAN4) A-55.
CAUTION: Disconnect the negative battery terminal. For details refer to SERVICE PRECAUTIONS .

CAUTION: A digital multimeter should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: The test wiring harness should be used. For details refer to SERVICE PRECAUTIONS .
1. Disconnect joint connector (CAN3), and measure the resistance at the wiring harness side of joint connector (CAN3).
2. Measure the resistance between joint connector (CAN3) terminal 6 and body ground.
  OK: 1 kilo ohm or more
  
  Fig 15: Measuring Resistance Between Joint Connector (CAN3) Terminal 6 And Body Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Measure the resistance between joint connector (CAN3) terminal 19 and body ground.
  OK: 1 kilo ohm or more
  
  Q: Do all the resistances measure 1 kilo ohm or more?
  1. YES: Go to Step 9.
  2. NO: Go to Step 16.
    
    Fig 16: Measuring Resistance Between Joint Connector (CAN3) Terminal 19 And Body Ground
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 9. Check the wiring harness between joint connector (CAN4) A-55 and transaxle assembly (TC-SST-ECU) connector B-120 for a short to ground. Measure the resistance at joint connector (CAN4) A-55.
CAUTION: Disconnect the negative battery terminal. For details refer to SERVICE PRECAUTIONS .

CAUTION: A digital multimeter should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: The test wiring harness should be used. For details refer to SERVICE PRECAUTIONS .
1. Disconnect joint connector (CAN3), and measure the resistance at the wiring harness side of joint connector (CAN3).
2. Measure the resistance between joint connector (CAN3) terminal 7 and body ground.
  OK: 1 kilo ohm or more
  
  Fig 17: Measuring Resistance Between Joint Connector (CAN3) Terminal 7 And Body Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Measure the resistance between joint connector (CAN3) terminal 20 and body ground.
  OK: 1 kilo ohm or more
  
  Q: Do all the resistances measure 1 kilo ohm or more?
  1. YES: Go to Step 10.
  2. NO: Go to Step 18.
    
    Fig 18: Measuring Resistance Between Joint Connector (CAN3) Terminal 20 And Body Ground
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 10. Check the wiring harness between joint connector (CAN3) C-124 and joint connector (CAN2) C-05 for a short to ground. Measure the resistance at joint connector (CAN3) C-124.
CAUTION: Disconnect the negative battery terminal. For details refer to SERVICE PRECAUTIONS .

CAUTION: A digital multimeter should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: The test wiring harness should be used. For details refer to SERVICE PRECAUTIONS .
1. Disconnect joint connector (CAN3), and measure the resistance at the wiring harness side of joint connector (CAN3).
2. Measure the resistance between joint connector (CAN3) terminal 5 and body ground.
  OK: 1 kilo ohm or more
  
  Fig 19: Measuring Resistance Between Joint Connector (Can3) Terminal 5 And Body Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Measure the resistance between joint connector (CAN3) terminal 16 and body ground.
  OK: 1 kilo ohm or more
  
  Q: Do all the resistances measure 1 kilo ohm or more?
  1. YES: Check intermediate connector A-54, and repair if necessary. If the intermediate connector is in good condition, repair the wiring harness between joint connector (CAN3) C-124 and joint connector (CAN4) A-55.
  2. NO: Check intermediate connector C-128, and repair if necessary. If the intermediate connector is in good condition, repair the wiring harness between joint connector (CAN3) C-124 and joint connector (CAN2) C-05.
    
    Fig 20: Measuring Resistance Between Joint Connector (CAN3) Terminal 16 And Body Ground
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 11. Using scan tool MB991958, diagnose the CAN bus line. (checking the steering wheel sensor for internal short to ground)
CAUTION: Strictly observe the specified wiring harness repair procedure. For details refer to SERVICE PRECAUTIONS .

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. Disconnect steering wheel sensor connector C-211.
2. Connect scan tool MB991958 to the data link connector.
3. Turn the ignition switch to the "ON" position.
  
  Fig 21: Connecting Scan Tool To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the illustration.
  OK: The display of the scan tool MB991958 is as shown in the illustration.
  
  Q: Does scan tool MB991958 screen correspond to the illustration?
  1. YES: Repair the wiring harness between steering wheel sensor connector C-211 and joint connector (CAN2) C-05.
  2. NO: Check steering wheel sensor connector C-211, and repair if necessary. If the steering wheel sensor connector is in good condition, replace the steering wheel sensor.
    
    Fig 22: Screen Display - CAN Bus Lines (Except Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    
    Fig 23: Screen Display - CAN Bus Lines (Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 12. Using scan tool MB991958, diagnose the CAN bus line. (checking the AWC-ECU for internal short to ground)
CAUTION: Strictly observe the specified wiring harness repair procedure. For details refer to SERVICE PRECAUTIONS .

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. Disconnect AWC-ECU connector C-51.
2. Connect scan tool MB991958 to the data link connector.
3. Turn the ignition switch to the "ON" position.
  
  Fig 24: Connecting Scan Tool To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the illustration.
  OK: The display of the scan tool MB991958 is as shown in the illustration.
  
  Q: Does scan tool MB991958 screen correspond to the illustration?
  1. YES: Repair the wiring harness between AWC-ECU connector C-51 and joint connector (CAN2) C-05.
  2. NO: Check AWC-ECU connector C-51, and repair if necessary. If the AWC-ECU connector is in good condition, replace the AWC-ECU.
    
    Fig 25: Screen Display - CAN Bus Lines (Except Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    
    Fig 26: Screen Display - CAN Bus Lines (Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 13. Check the wiring harness between joint connector (CAN2) C-05 and ETACS-ECU connector C-301 for a short to ground.
CAUTION: Disconnect the negative battery terminal. For details refer to SERVICE PRECAUTIONS .

CAUTION: A digital multimeter should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: The test wiring harness should be used. For details refer to SERVICE PRECAUTIONS .

CAUTION: Strictly observe the specified wiring harness repair procedure. For details refer to SERVICE PRECAUTIONS .
1. Disconnect ETACS-ECU connector and joint connector (CAN2), and measure at the wiring harness side.
2. Measure the resistance between joint connector (CAN2) terminal 6 and body ground.
  OK: 1 kilo ohm or more
  
  Fig 27: Measuring Resistance Between Joint Connector (CAN2) Terminal 6 And Body Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Measure the resistance between joint connector (CAN2) terminal 19 and body ground.
  OK: 1 kilo ohm or more
  
  Q: Do all the resistances measure 1 kilo ohm or more?
  1. YES: Check ETACS-ECU connector C-301, and repair if necessary. If the ETACS-ECU connector is in good condition, replace the ETACS-ECU.
  2. NO: Repair the wiring harness between ETACS-ECU connector C-301 and joint connector (CAN2) C-05.
    
    Fig 28: Measuring Resistance Between Joint Connector (CAN2) Terminal 19 And Body Ground
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 14. Using scan tool MB991958, diagnose the CAN bus line. (checking the ASC-ECU for internal short to ground)
CAUTION: Strictly observe the specified wiring harness repair procedure. For details refer to SERVICE PRECAUTIONS .

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. Disconnect ASC-ECU connector A-51.
2. Connect scan tool MB991958 to the data link connector.
3. Turn the ignition switch to the "ON" position.
  
  Fig 29: Connecting Scan Tool To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the illustration.
  OK: The display of the scan tool MB991958 is as shown in the illustration.
  
  Q: Does scan tool MB991958 screen correspond to the illustration?
  1. YES: Repair the wiring harness between ASC-ECU connector A-51 and joint connector (CAN3) C-124.
  2. NO: Check ASC-ECU connector A-51, and repair if necessary. If the ASC-ECU connector is in good condition, replace the ASC-ECU.
    
    Fig 30: Screen Display - CAN Bus Lines (Except Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    
    Fig 31: Screen Display - CAN Bus Lines (Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 15. Using scan tool MB991958, diagnose the CAN bus line. (checking the TCM for internal short to ground)
CAUTION: Strictly observe the specified wiring harness repair procedure. For details refer to SERVICE PRECAUTIONS .

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. Disconnect TCM connector C-41.
2. Connect scan tool MB991958 to the data link connector.
3. Turn the ignition switch to the "ON" position.
  
  Fig 32: Connecting Scan Tool To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the illustration.
  OK: The display of the scan tool MB991958 is as shown in the illustration.
  
  Q: Does scan tool MB991958 screen correspond to the illustration?
  1. YES: Repair the wiring harness between TCM connector C-41 and joint connector (CAN3) C-124.
  2. NO: Check TCM connector C-41, and repair if necessary. If the TCM connector is in good condition, replace the TCM.
    
    Fig 33: Screen Display - CAN Bus Lines (Except Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    
    Fig 34: Screen Display - CAN Bus Lines (Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 16. Using scan tool MB991958, diagnose the CAN bus line. (checking the ECM for internal short to ground)
CAUTION: Strictly observe the specified wiring harness repair procedure. For details refer to SERVICE PRECAUTIONS .

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. Disconnect ECM connector B-109.
2. Connect scan tool MB991958 to the data link connector.
3. Turn the ignition switch to the "ON" position.
  
  Fig 35: Connecting Scan Tool To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the illustration.
  OK: The display of the scan tool MB991958 is as shown in the illustration.
  
  Q: Does scan tool MB991958 screen correspond to the illustration?
  1. YES: Repair the wiring harness between ECM connector B-109 and joint connector (CAN3) C-124 <except RALLIART>, or check intermediate connector A-54, and repair if necessary. If the intermediate connector is in good condition, repair the wiring harness between ECM connector B-109 and joint connector (CAN4) A-55 <RALLIART>.
  2. NO: Check ECM connector B-109, and repair if necessary. If the ECM connector is in good condition, replace the ECM.
    
    Fig 36: Screen Display - CAN Bus Lines (Except Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    
    Fig 37: Screen Display - CAN Bus Lines (Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 17. Using scan tool MB991958, diagnose the CAN bus line. (checking the shift lever for internal short to ground)
CAUTION: Strictly observe the specified wiring harness repair procedure. For details refer to SERVICE PRECAUTIONS .

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. Disconnect shift lever connector C-49.
2. Connect scan tool MB991958 to the data link connector.
3. Turn the ignition switch to the "ON" position.
  
  Fig 38: Connecting Scan Tool To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the illustration.
  OK: The display of the scan tool MB991958 is as shown in the illustration.
  
  Q: Does scan tool MB991958 screen correspond to the illustration?
  1. YES: Repair the wiring harness between shift lever connector C-49 and joint connector (CAN3) C-124.
  2. NO: Check shift lever connector C-49, and repair if necessary. If the shift lever connector is in good condition, replace the shift lever.
    
    Fig 39: Screen Display - CAN Bus Lines (Except Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    
    Fig 40: Screen Display - CAN Bus Lines (Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 18. Using scan tool MB991958, diagnose the CAN bus line. (checking the transaxle assembly (TC-SST-ECU) connector for internal short to ground)
CAUTION: Strictly observe the specified wiring harness repair procedure. For details refer to SERVICE PRECAUTIONS .

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. Disconnect transaxle assembly (TC-SST-ECU) connector B-120.
2. Connect scan tool MB991958 to the data link connector.
3. Turn the ignition switch to the "ON" position.
  
  Fig 41: Connecting Scan Tool To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Diagnose CAN bus lines, and check if the scan tool MB991958 screen is as shown in the illustration.
  OK: The display of the scan tool MB991958 is as shown in the illustration.
  
  Q: Does scan tool MB991958 screen correspond to the illustration?
  1. YES: Repair the wiring harness between transaxle assembly (TC-SST-ECU) connector B-120 and joint connector (CAN4) A-55.
  2. NO: Check transaxle assembly (TC-SST-ECU) connector B-120, and repair if necessary. If the transaxle assembly (TC-SST-ECU) connector is in good condition, replace the transaxle assembly (TC-SST-ECU).
    
    Fig 42: Screen Display - CAN Bus Lines (Except Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    
    Fig 43: Screen Display - CAN Bus Lines (Ralliart)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.