Code No.B1457: Side Impact Sensor (Rear) (LH) Power Supply Circuit System





caution If diagnosis code B1447 is set in the SRS-ECU, always diagnose the CAN main bus line.

OPERATION


The side impact sensor (Rear) includes an analogue G sensor and CPU, etc. The CPU monitors the analogue G sensor output signal. If the CPU judges that the curtain air bags should be deployed, it sends a fire signal to the SRS-ECU to deploy the curtain air bags. In addition, the CPU diagnoses the internal components of the side impact sensor (Rear). If a malfunction occurs, it requests the SRS-ECU to set a diagnosis code.

DIAGNOSIS CODE SET CONDITIONS


This diagnosis code will set when the power supply voltage to the side impact sensor (Rear) (RH) remains less than a predetermined value for five seconds.

PROBABLE CAUSES




DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III CAN bus diagnostics


Use the 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 54F, Diagnosis ).

STEP 2. Check whether the diagnosis code is reset.


Check again if the diagnosis code is set.
(1)Erase the diagnosis code.
(2)Ignition: LOCK (OFF) position to ON
(3)On completion, check that the diagnosis code is not reset.

Q. Is the diagnosis code set?

Go to Step 3 .
There is an intermittent malfunction such as poor engaged connector(s) or open circuit (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).

STEP 3. Check the harness wires for open circuit or short circuit between SRS-ECU connector C-120 (terminal No.15 and 16) and side impact sensor (Rear) (LH) connector D-12 (terminal No.1 and 2).




Q. Are the harness wires between SRS-ECU connector C-120 (terminal No.15 and 16) and side impact sensor (Rear) (LH) connector D-12 (terminal No.1 and 2) in good condition?

Go to Step 4 .

Replace the harness wires between SRS-ECU connector C-120 (terminal No.15 and 16) and side impact sensor (Rear) (LH) connector D-12 (terminal No.1 and 2).

STEP 4. Check the side impact sensor (Rear) (LH) (M.U.T.-III diagnosis code).


(1)Disconnect the negative battery terminal.
(2)Replace the side impact sensor (Rear) (LH) with the side impact sensor (Rear) (RH).
(3)Connect the negative battery terminal.
(4)Erase diagnosis code from memory, and check the diagnosis code.

Q. Is diagnosis code B1457 set?

Replace the SRS-ECU (Refer to ).
Replace the side impact sensor (Rear) (LH) with a new one (Refer to ). Go to Step 5.

STEP 5. Check whether the diagnosis code is reset.


Q. Is diagnosis code B1457 set?

Replace the SRS-ECU (Refer to ).
An intermittent malfunction is suspected (Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points ).