DTC B1410: Passenger's (Front) Air Bag Module (1st Squib) System Fault 1 (Short Circuit between Terminals of the Squib Circuit): DTC B1490: Passenger's (Front) Air Bag Module (2nd Squib) System Fault 1 (Short Circuit between Terminals of the Squib Circuit): Diagnosis
Required Special Tools:
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: MUT-III USB Cable
- MB991911: MUT-III Main Harness B
- MB991865: Dummy resister
- MB991866: Resister harness
- STEP 1. Using scan tool MB991958, read the diagnostic trouble code.
Q: Is DTC B1519 set?
YES : Go to Step 2.
NO : Go to Step 3.
- STEP 2. Check SRS-ECU connector C-28.
Q: Is the connector correctly engaged?
YES : Go to Step 3.
NO : Engage the connector correctly. Then go to Step 7.
- STEP 3. Check SRS-ECU connector C-28 and passenger's air bag module connector C-106. (Using scan tool MB991958, read the diagnostic trouble code.)
- Disconnect the negative battery terminal.
- Disconnect connectors C-28 and C-106, and then reconnect them.
- Slide the outer housing of the clock spring side of driver's air bag module connector C-106 in the arrow direction shown, and disconnect the connector.
- Connect the negative battery terminal.CAUTION: Always DTC B1491 is set when checking DTC B1410. This is because the second side terminal is isolated when checking it, DTC B1491 is set but this is not a fault. In addition, always DTC B1411 is set when checking DTC B1490 because the first side terminal is isolated.
- Erase the diagnostic trouble code memory, and check the diagnostic trouble code.
Q: Is DTC B1410 < 1st squib > or B1490 < 2nd squib > set?
YES : Go to Step 4.
NO : The procedure is complete. It is assumed that DTC B1410 < 1st squib > or B1490 < 2nd squib > set as connector C-28 or C-106 was engaged improperly.
- STEP 4. Check the passenger's air bag module. (Using scan tool MB991958, read the diagnostic trouble code.)
- Disconnect the negative battery terminal.
- Disconnect the passenger's air bag module connector C-106.
- Slide the outer housing of the clock spring side of passenger's air bag module connector C-106 in the arrow direction shown, and disconnect the connector.
- Connect special tool MB991865 to special tool MB991866.CAUTION: Do not insert a test probe into the terminal from its front side directly as the connector contact pressure may be weakened.
- Insert special tool MB991866 into the harness side connector C-106 (terminal No.1 and 2 < 1st squib > or terminal No.3 and 4 < 2nd squib >) by backprobing.
- Connect the negative battery terminal.CAUTION: Always DTC B1491 is set when checking DTC B1410. This is because the second side terminal is isolated when checking it, DTC B1491 is set but this is not a fault. In addition, always DTC B1411 is set when checking DTC B1490 because the first side terminal is isolated.
- Erase the diagnostic trouble code memory, and check the diagnostic trouble code.
Q: Is DTC B1410 < 1st squib > or B1490 < 2nd squib > set?
YES : Go to Step 5.
NO : Replace the passenger's air bag module (refer to AIR BAG MODULE(S) AND CLOCK SPRING ). Then go to Step 7.
- STEP 5. Check the passenger's air bag module circuit at SRS-ECU connector C-28.
- Disconnect the negative battery terminal.
- Disconnect SRS-ECU connector C-28.
WARNING: To prevent the air bag from deploying unintentionally, disconnect the passenger's air bag module connector C-106 to short the squib circuit.
- Disconnect the passenger's air bag module connector C-106.
- Slide the outer housing of the clock spring side of passenger's air bag module connector C-106 in the arrow direction shown, and disconnect the connector.
CAUTION: Insert an insulator such as a cable tie to a depth of 4mm (0.16 inch) or more, otherwise the short spring will not be released.
- Insert a cable tie [3 mm (0.12 inch) wide, 0.5 mm (0.02 inch) thick] between terminals 27 and 28 < 1st squib > or 30 and 31 < 2nd squib >, and the short spring to release the short spring.
CAUTION: Do not insert a test probe into the terminal from its front side directly as the connector contact pressure may be weakened.
- Check for continuity between C-28 harness side connector terminals 27 and 28 < 1st squib > or 30 and 31 < 2nd squib >. It should be open circuit.
Q: Does continuity exist?
YES : Go to Step 6.
NO : Erase the diagnostic trouble code memory, and check the diagnostic trouble code. If DTC B1410 < 1st squib > or B1490 < 2nd squib > set, replace the SRS-ECU (refer to SRS CONTROL UNIT (SRS-ECU) ). Then go to Step 7.
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
- STEP 6. Check the harness for short circuit between SRS-ECU connector C-28 (terminal No.27 and 28 < 1st squib > or terminal No.30 and 31 < 2nd squib >) and passenger's air bag module connector C-106 (terminal No.1 and 2 < 1st squib > terminal No.4 and 3 < 2nd squib >).
Q: Are harness wires between SRS-ECU connector C-28 (terminal No.27 and 28 < 1st squib > or terminal No.30 and 31 < 2nd squib >) and passenger's air bag module connector C-106 (terminal No.1 and 2 < 1st squib > terminal No.4 and 3 < 2nd squib >) in good condition?
YES : Go to Step 7.
NO : Replace the harness wires between SRS-ECU connector C-28 and passenger's air bag module connector C-106. Then go to Step 7.
- STEP 7. Check for diagnostic trouble code.
Check again if the DTC is set.
- Erase the DTC.
- Turn the ignition switch to the "ON" position.
- Check if the DTC is set.
- Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC B1410 < 1st squib > or B1490 < 2nd squib > set?
YES : Return to Step 1.
NO : The procedure is complete.