Code No. B1206 Passenger’s air bag OFF indicator lamp (open circuit)
















caution If the diagnosis code B1206 is set in the SRS-ECU, be sure to diagnose the CAN bus line

OPERATION



  • Power for the passenger’s air bag OFF indicator lamp is supplied from the fusible link (34) or (44).
  • The passenger’s air bag OFF indicator lamp 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 JUDGEMENT



PROBABLE CAUSES



  • Damaged wiring harnesses or connectors
  • Malfunction of the SRS-ECU
  • Malfunction of the instrument centre panel (passenger’s air bag OFF indicator lamp)

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics.
Use M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?
Go to Step 2.
Repair the CAN bus line (Refer to GROUP 54C - Troubleshooting ).

STEP 2. Check whether the diagnosis code is reset.
(1)Connect the negative battery terminal.
(2)After erasing the diagnosis code memory, check the diagnosis code again.
(3)Disconnect the negative battery terminal.

Q. Is the diagnosis code No. B1206 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 instrument centre panel.
(1)It is checked whether instrument centre panel is normal (Refer to ).

Q. Is the check result normal?
Go to Step 4.
Replace instrument centre panel (Refer to GROUP 52A - Instrument Centre Panel ).

STEP 4. Resistance measurement at the C-122 SRS-ECU connector terminal No.18 and the C-10 instrument centre panel connector terminal No.11.
(1)Disconnect the negative battery terminal.

(2)While pushing the part "A" indicated in the figure of the harness side connector, turn the lock lever to the direction of the arrow to release the lock lever, and disconnect the C-122 SRS-ECU connector.
(3)Disconnect the C-10 instrument centre panel connector.
(4)Take the measurements below at the C-122 and C-10 wiring harness side connectors.

  • Continuity between C-122 SRS-ECU connector terminal No. 18 and C-10 instrument centre panel connector terminal No. 11
OK: Continuity (less than 2 Ω)

Q. Is the check result normal?

Go to Step 5.

Repair the wiring harnesses between the C-122 SRS-ECU connector terminal No. 18 and the C-10 instrument centre panel connector terminal No. 11.

STEP 5. Measure the voltage at the instrument centre panel connector.
(1)Disconnect the C-10 instrument centre panel connector.
(2)Connect the negative battery terminal.
(3)Ignition switch: ON
(4)Measure the voltage between the C-10 harness side connector terminal No. 8 and the body earth.
OK: Battery voltage

Q. Is the check result normal?
Go to Step 6.
Repair the wiring harness between the C-317 ETACS-ECU connector terminal No. 5 and the C-10 instrument centre panel connector terminal No. 8.

STEP 6. Check whether the diagnosis code is reset.

Q. Is the diagnosis code No. B1206 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 ).