DTC B1BAA: Occupant Classification-ECU Configuration Mismatch: Diagnosis

Required Special Tools:

MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicles Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

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 ."
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?
- YES: Go to Step 2.
- NO: Repair the CAN bus line (Refer to DIAGNOSIS ).
  
  Fig 1: Connecting Special Tool MB991910 To Data Link Connector
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 2. Using scan tool MB991958, read the ETACS-ECU diagnostic trouble code
Check if DTC B1761, B222C, B2206, B2215 or U0331 is set to the ETACS-ECU.

Q: Is the DTC set?
- YES: Troubleshoot the ETACS-ECU (Refer to DIAGNOSIS ). Then go to Step 4.
- NO: Go to Step 3.
STEP 3. Using scan tool MB991958, read the occupant classification-ECU diagnostic trouble code
Check if DTC B1B91 is set to the occupant classification-ECU.

Q: Is the DTC set?
- YES: Troubleshoot the occupant classification-ECU (Refer to DIAGNOSTIC TROUBLE CODE TABLE < Occupant classification-ECU > ). Then go to Step 4.
- NO: Go to Step 4.
STEP 4. Recheck for diagnostic trouble code.
Check again if the DTC is set to the SRS-ECU.
1. Erase the DTC.
2. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
3. Check if DTC is set.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
- YES: Replace the SRS-ECU (Refer to SRS CONTROL UNIT (SRS-ECU) ).
- NO: There is an intermittent malfunction such as poor engaged connector(s) or open circuit (Refer to HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS ).