Code No. B1647 Passenger’s air bag ON indicator lamp (short circuited)



caution If the diagnosis code B1488 is set in the SRS-ECU, be sure to diagnose the CAN bus line

OPERATION




TROUBLE JUDGEMENT


This code will be set if the passenger’s air bag ON indicator lamp driving circuit is short to earth.

PROBABLE CAUSES




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. B1647 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 ON indicator lamp.


It is checked whether passenger’s air bag ON indicator lamp is normal (Refer to ).

Q. Is the check result normal?

Go to Step 4.
Replace hazard indicator assembly (Refer to GROUP 52A - Instrument Panel Assembly ).

STEP 4. Resistance measurement at the SRS-ECU connector.


(1)Check that the negative battery terminal is disconnected. If the negative battery terminal is connected, disconnect it.

(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 SRS-ECU connector.
(3)Disconnect the hazard indicator assembly connector.
(4)Take the measurements below at the SRS-ECU connector.

  • Continuity between ONLP line and body earth
OK: No continuity

Q. Is the check result normal?

Go to Step 5.

Repair the wiring harnesses ONLP line between the SRS-ECU connector and the hazard indicator assembly connector.

STEP 5. Resistance measurement at the hazard indicator assembly connector.


(1)Check that the negative battery terminal is disconnected. If the negative battery terminal is connected, disconnect it.

(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 SRS-ECU connector.
(3)
caution Do not insert a test probe into the terminal from its front side directly as the connector contact pressure may be weakened.
Take the following measurements at the backside of the hazard indicator assembly side connector (harness side).

  • Continuity between LP line and body earth
OK: No continuity

Q. Is the check result normal?

Go to Step 6

Repair the wiring harnesses LP line between the hazard indicator assembly connector and the body earth.

STEP 6. Check whether the diagnosis code is reset.


Q. Is the diagnosis code No. B1647 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 ).