Inspection Procedure 8: Seat belt reminder function does not work normally: Diagnosis

Required Special Tools: 

• MB991223: Harness Set
• MB992006: Extra Fine Probe

1. STEP 1. Using scan tool MB991958, diagnose the CAN bus line. 
   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. Refer to "HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ."
   2. Turn the ignition switch to the "ON" position.
   3. Diagnose the CAN bus line.
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the CAN bus line found to be normal? 

   1. YES:  Go to Step 2.
   2. NO:  Repair the CAN bus line (Refer to PRECAUTIONS ON HOW TO REPAIR THE CAN BUS LINES ).
2. STEP 2. Using scan tool MB991958, read for SRS diagnostic trouble code. 

   Check the DTC is set to the SRS.

   Q: Is the DTC set? 

   1. YES:  Troubleshoot the SRS (Refer to SRS DIAGNOSTIC TROUBLE CODE CHART < OCCUPANT CLASSIFICATION-ECU > ).
   2. NO:  Go to Step 3.
3. STEP 3. Check seat belt switch (driver's side) connector D-33 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is seat belt switch (driver's side) connector D-33 in good condition? 

   1. YES:  Go to Step 4.
   2. NO:  Repair the defective connector.
4. STEP 4. Check the seat belt switch. 

   Refer to FRONT SEAT BELT .

   Q: Is the check result normal? 

   1. YES:  Go to Step 5.
   2. NO:  Replace the seat belt switch.
5. STEP 5. Check the ground circuit to the seat belt switch (driver's side). Test at seat belt switch (driver's side) connector D-33. 
   1. Disconnect the connector, and measure at the wiring harness side.
   2. Measure the resistance value between terminal 1 and ground.
      • The resistance should be 2 ohms or less.

   Q: Is the measured resistance 2 ohms or less? 

   1. YES:  Go to  Step 7.
   2. NO:  Go to Step 6.
      Fig 1: Checking Seat Belt Switch Ground Circuit (Driver Side)

      Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
6. STEP 6. Check the wiring harness between seat belt switch (driver's side) connector D-33 (terminal 1) and ground. 

   Check the ground wire for open circuit.

   Q: Is the wiring harness between seat belt switch (driver's side) connector D-33 (terminal 1) and ground in good condition? 

   1. YES:  The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
   2. NO:  Repair the wiring harness.
7. STEP 7. Check combination meter connector C-203 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is combination meter connector C-203 in good condition? 

   1. YES:  Go to Step 8.
   2. NO:  Repair the defective connector.
8. STEP 8. Check the wiring harness between combination meter connector C-203 (terminal 5) and seat belt switch < driver's side > connector D-33 (terminal 2). 
   • Check the input line for open and short circuit.
     NOTE: Also check intermediate connector C-26 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-26 is damaged, repair or replace the damaged component(s) as described in HARNESS CONNECTOR INSPECTION .

   Q: Is the wiring harness between combination meter connector C-203 (terminal 5) and seat belt switch < driver's side > connector D-33 (terminal 2) in good condition? 

   1. YES:  Go to Step 9.
   2. NO:  Repair the wiring harness.
9. STEP 9. Check center panel unit connector C-205 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is center panel unit connector C-205 in good condition? 

   1. YES:  Go to Step 10.
   2. NO:  Repair the defective connector.
10. STEP 10. Check the wiring harness between combination meter connector C-203 (terminal 19) and center panel unit connector C-205 (terminal 16). 
    • Check the input line for open and short circuit.

    Q: Is the wiring harness between combination meter connector C-203 (terminal 19) and center panel unit connector C-205 (terminal 16) in good condition? 

    1. YES:  Go to Step 11.
    2. NO:  Repair the wiring harness.
11. STEP 11. Retest the system. 

    The seat belt reminder function should work normally.

    Q: Is the check result normal? 

    1. YES < The seat belt reminder function works normally. >:  The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
    2. NO < Tone alarm sounds do not sound. >:  Replace the combination meter.
    3. NO < The indicator (driver's side) does not illuminate. >:  Replace the combination meter.
    4. NO < The indicator (passenger's side) does not illuminate. >:  Replace the center panel unit.