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DTC B1489 Passenger’s air bag OFF indicator light (open circuit)
 
 
cautionIf DTC B1489 is set in the SRS-ECU, be sure to diagnose the CAN bus line
 
 
OPERATION
  • Power for the passenger’s air bag OFF indicator light is supplied from the fusible link (40).
  • The passenger’s air bag OFF indicator light illuminates when the ignition switch is turned to the "ON" position and goes out after approximately 6 to 8 seconds if there is not a malfunction in the SRS system.
 
 
TROUBLE JUDGMENT
This code will be set if an open circuit has occurred in the wiring harness between the passenger’s air bag OFF indicator light and the SRS-ECU.
 
 
PROBABLE CAUSES
  • Damaged wiring harnesses or connectors
  • Malfunction of the SRS-ECU
  • Malfunction of the passenger’s air bag OFF indicator light
 
 
DIAGNOSIS
STEP 1. Using scan tool (M.U.T.-IIISE), diagnose the CAN bus line.
(1)
cautionTo prevent damage to scan tool (M.U.T.-IIISE), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-IIISE).
Connect scan tool (M.U.T.-IIISE). 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.
Is the CAN bus line found to be normal?
Go to Step 2.
Repair the CAN bus line (Refer to GROUP 54C, Diagnosis ).
 
STEP 2. Using scan tool (M.U.T.-IIISE), check whether the DTC is set again.
(1) Connect the negative battery terminal.
(2) After erasing the DTC memory, check the DTC again.
(3) Disconnect the negative battery terminal.
Is DTC B1489 set?
Go to Step 3.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
 
STEP 3. Check the passenger’s air bag OFF indicator light.
It is checked whether passenger’s air bag OFF indicator light is normal (Refer to ).
Is the check result normal?
Go to Step 4.
Replace hazard warning light switch (Refer to GROUP 52A - Instrument Panel Assembly ).
 
STEP 4. Resistance measurement at the SRS-ECU connector and the hazard warning light switch connector.
(1) Check that the negative battery terminal is disconnected. If the negative battery terminal is connected, disconnect it.
(2) Disconnect the SRS-ECU connector.
(3) Disconnect the hazard warning light switch connector.
(4) Take the measurements below at the SRS-ECU and hazard warning light switch wiring harness side connectors.
  • Continuity OFLP line between SRS-ECU connector and hazard warning light switch connector
OK: The resistance should be 2 ohms or less
Is the check result normal?
Go to Step 5.
Repair the wiring harnesses OFLP line between the SRS-ECU connector and the hazard warning light switch connector.
 
STEP 5. Measure the voltage at the hazard warning light switch connector.
(1) Disconnect the hazard warning light switch connector.
(2) Connect the negative battery terminal.
(3) Ignition switch: ON
(4) Measure the voltage between the hazard warning light switch harness side connector and the body ground.
OK: The voltage should measure approximately 12 volts (battery positive voltage).
Is the check result normal?
Go to Step 6.
Repair the wiring harness IG+ line between the ETACS-ECU connector and the hazard warning light switch connector.
 
STEP 6. Using scan tool (M.U.T.-IIISE), check whether the DTC is set again.
Is DTC B1489 set?
Replace SRS-ECU (Refer to ).
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).