Mitsubishi Outlander: SRS Air Bag Diagnosis

INTRODUCTION TO DIAGNOSIS

The SRS system is controlled by the SRS-ECU. The SRS-ECU judges how severe a collision is by detecting signals from the left and right front impact sensors and side impact sensors, front air bag analog G-sensor and front air bag safing G-sensor and side-airbag safing G-sensor. If the impact is over a predetermined level, the SRS-ECU sends an ignition signal. At this time, if the safing G-sensor is on, the SRS air bag will inflate. (The passenger's air bag may not inflate according to the occupant detection data from the occupant classification-ECU.) The SRS warning light in the combination meter alerts a malfunction of the SRS system. If the following symptoms occur even when the vehicle has not been in a collision, there may be a malfunction in the SRS system.

• The SRS warning light does not go off within approximately seven seconds after the ignition switch has been turned to the "ON" position.
• The SRS warning light does not illuminate when the ignition switch is turned to the "ON" position.

Refer to Post-collision Diagnosis when inspecting and servicing a vehicle that has been in a collision.

TROUBLESHOOTING STRATEGY

Use these steps to plan your diagnostic strategy. If you follow them carefully, you will be sure that you have exhausted all of the possible ways to find a SRS fault.

1. Gather information about the problem from the customer.

2. Verify that the condition described by the customer exists.

3. Check the vehicle for any SRS diagnostic trouble codes (SRS DTC).

4. If you cannot verify the condition but there are no SRS DTCs, the malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting − Inspection Service Points − How to Cope with Intermittent Malfunctions.

5. If there is a SRS DTC, record the code number, then erase the code from vehicle memory using scan tool (M.U.T.-III Sub Assembly) MB991958.

6. Recreate the SRS DTC set conditions to see if the same SRS DTC will be set again.

• If the same SRS DTC is set again, follow the Inspection Chart for the DTC and find the fault.
• If you cannot get the same SRS DTC to be set again, the malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting − Inspection Service Points − How to Cope with Intermittent Malfunctions.

DIAGNOSTIC FUNCTION

HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)

Required Special Tools:

• 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

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. Ensure that the ignition switch is at the "LOCK" (OFF) position.

2. Start up the personal computer.

3. Connect special tool MB991827 to special tool MB991824 and the personal computer.

4. Connect special tool MB991910 to special tool MB991824.

5. Connect special tool MB991910 to the data link connector.

6. Turn the power switch of special tool MB991824 to the "ON" position.

NOTE: When special tool MB991824 is energized, special tool MB991824 indicator light will be illuminated in a green color.

7. Start the M.U.T.-III system on the personal computer.

NOTE: Disconnecting scan tool MB991958 is the reverse of the connecting sequence, making sure that the ignition switch is at the "LOCK" (OFF) position.

HOW TO READ AND ERASE DIAGNOSTIC TROUBLE CODES

Required Special Tools:

• 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

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.

NOTE: If the battery voltage is low, diagnostic trouble codes will not be set. Check the battery if scan tool MB991958 does not display.

1. Connect scan tool MB991958 to the data link connector.

2. Turn the ignition switch to the "ON" position.

3. Select "System select" from the start-up screen.

4. Select "From 2006 MY" of "Model Year". When the "Vehicle Information" is displayed, check the contents.

5. Select "SRS-AIR BAG" from "System List", and press the "OK" button.

NOTE: When the "Loading Option Setup" list is displayed, check the applicable item.

6. Select "Diagnostic Trouble Code" to read the DTC.

7. If a DTC is set, it is shown.

8. Choose "Erase DTCs" to erase the DTC.

SRS WARNING LIGHT CHECK

1. Check that the SRS warning light illuminates when the ignition switch is in the "ON" position.

2. Check that it illuminates for approximately seven seconds and then goes out.

3. If not, check for DTC.

PASSENGER'S SEAT BELT WARNING LIGHT CHECK

When an adult on the front passenger's seat wears the seat belt with the ignition switch "ON", confirm that the passenger's seat belt warning light goes out.

The light comes on when a person sits on the front passenger seat but does not fasten the seat belt.

PASSENGER'S AIR BAG OFF INDICATOR LIGHT CHECK

SYSTEM CHECK

Check that the passenger's air bag OFF indicator light illuminates when the ignition switch is in the "ON" position.

Check that it illuminates for approximately seven seconds and then goes out.

In the following situations, the indicator will stay on to show that the passenger's (front) air bag is not operational.

• The occupant classification-ECU and weight sensor sense 66 pounds (30 kg) on the front passenger seat.
• The front passenger's seat is not occupied.

ILLUMINATION CHECK

1. Remove the center panel assembly.

2. Connect the positive battery terminal with the center panel assembly connector terminal No. 8. Then, check if the passenger's air bag OFF indicator light is illuminated when the negative battery terminal and the center panel assembly connector terminal No. 11 are connected.

3. If the passenger's air bag OFF indicator light is illuminated, it is judged good.

CHECK CHART FOR DIAGNOSIS CODES

CAUTION During diagnosis, a DTC code associated with another system may be set when the ignition switch is turned on with connector(s) disconnected. After completing the repair, confirm all systems for DTC code(s). If DTC code(s) are set, erase them all.

Inspect according to the inspection chart that is appropriate for the DTC.

• DTC B1206, B1207, B1B00, B1B01, B1B02, B1B03, B1B04, B1B05, B1B06, B1B07
• DTC B1B08, B1B09, B1B0A, B1B0B, B1B0C, B1B0D, B1B0E, B1B0F, B1B18, B1B19
• DTC B1B1A, B1B1B, B1B20, B1B21, B1B22, B1B23
• DTC B1B54, B1B55, B1B56, B1B70, B1B71, B1B72, B1B73, B1B75, B1B76, B1BA3, B1BA4, B1BA5, B1BAA, B1BC7, B1BCF
• DTC B1C27, B1C28, B1C29, B1C2A, B1C2B, B1C2C, B1C2D, B1C2E
• DTC B1C33, B1C34, B1C35, B1C36, B1C38, B1C39, B1C3A, B1C3B
• DTC B1C47, B1C48, B1C49, B1C4A, B210D, B212C,  B212D
• DTC U0019, U0141, U0154, U0155, U0164, U0168, U0170, U0171, U0172, U0173, U0175, U0176, U0184, U0195, U0212, U1414, U1415
• DTC B1B78, B1B79, B1B7A, B1B7D, B1B7E, B1B7F, B1B82, B1B83, B1B84, B1B87, B1B88, B1B89, B1B8C, B1B8D, B1B8E, B1B91, B1BA7, B1BA8
• DTC B1BBA, B1BBC, B1BBD, B1C23, B1C24, B1C25, B1C26, B1CB2, B210D, B210E, B2206, B2212, B2250, B2262
• DTC U0020, U0021, U0022, U0023, U0024, U0025, U0026, U0141, U0151, U0155, U0164, U0168, U0184, U0195, U0245, U1419, U141A, U141B, U141C, U1423

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