B1488

DTC B1488: Passenger Air Bag OFF Indicator Light Drive Circuit System Fault 2.

Passenger Air Bag Off Indicator Light Drive Circuit:

CAUTION: If DTC B1488 is set in the SRS-ECU, always diagnose the CAN main bus line.

CIRCUIT OPERATION
- Power for the passenger air bag OFF indicator light is supplied from the ignition switch (IG1).
- The passenger air bag OFF indicator light illuminates when the ignition switch is turned to the "ON" position and goes out after approximately seven seconds if there is not a malfunction in the SRS system.

DTC SET CONDITIONS
- This DTC is set under one of the following cases while the SRS-ECU is monitoring the passenger air bag OFF indicator light drive circuit:
- When a short circuit occurs in the passenger air bag OFF indicator light drive circuit.
- When a malfunction is detected in the output transistor inside the SRS-ECU.

However, if the vehicle condition returns to normal, DTC B1488 will be automatically erased, and the passenger air bag OFF indicator light will go out.

TROUBLESHOOTING HINTS
- Damaged wiring harnesses or connectors
- Malfunction of the SRS-ECU

DIAGNOSIS

Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A

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." Scan Tool Connecting
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 : Replace the SRS-ECU.

NO : Repair the CAN bus line (Refer to Controller Area Network (CAN), Diagnosis).