The SRS-ECU judges how severe a collision is by detecting signals from the left and right side impact sensors. If the impact is over a predetermined level, the SRS-ECU sends an ignition signal. At this time, if the side-airbag safing G-sensor is on, the SRS side-airbag will inflate.
The ignition signal is input to the side-airbag module to inflate the side-airbag.
DIAGNOSIS CODE SET CONDITIONS
Open circuit in the side-airbag module (squib) (LH) circuit
Improper connector contact
Malfunction of the SRS-ECU
STEP 1. M.U.T.-III CAN bus diagnostics.
Is the CAN bus line found to be normal?
STEP 2. Check whether the diagnosis code is reset.
Is the diagnosis code set?
STEP 3. Check the side-airbag module (LH) (M.U.T.-III diagnosis code).
Is diagnosis code B1431 set?
STEP 4. Resistance measurement between the SRS-ECU connector B-109 (terminal No.15 and 16) and the side-airbag module connector C-20 (terminal No.1 and 2).
SRS-ECU connector B-109 (terminal No.15) and the male side connector C-20 (SRS-ECU side) (terminal No.1)
SRS-ECU connector B-109 (terminal No.16) and the male side connector C-20 (SRS-ECU side) (terminal No.2)
Are the check result normal?
STEP 5. Check the side-airbag module (RH) (M.U.T.-III diagnosis code).
Is diagnosis code B1420 set?
STEP 6. Check whether the diagnosis code is reset.