Code No.B1408: Front impact sensor (RH) communication error
Code No.B1409: Front impact sensor (RH) communication impossible











caution If diagnosis code B1408 or B1409 is set in the SRS-ECU, always diagnose the CAN main bus line.

OPERATION


The front impact sensor transmits acceleration data to the SRS-ECU. The SRS-ECU then determines whether to operate the front air bags, and then outputs an ignition signal when necessary. The front impact sensor also diagnoses itself, and sends a diagnosis code to the SRS-ECU if a malfunction occurs

DIAGNOSIS CODE SET CONDITIONS


These diagnosis codes are set if communication between the front impact sensor (RH) and the SRS-ECU is not possible or faulty.

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 54D, 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 front impact sensor (RH).


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

Q. Is diagnosis code B1418 or B1419 set?

Replace the front impact sensor (RH) with a new one (Refer to ). Than go to Step 4.
Repair the harness wires between SRS-ECU connector D-24 (terminal No.47 and 48) and front impact sensor (RH) connector A-37 (terminal No.2 and 1).Than go to Step 4.

STEP 4. Check whether the diagnosis code is reset.


Q. Is diagnosis code B1408 or B1409 set?

Replace the SRS-ECU (Refer to ).
An intermittent malfunction is suspected (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).