diagnosis code
B1433: Side-Airbag Module (LH) (Squib) System Fault Power Supply Circuit
(Short-Circuited to
Power Supply)
| caution |
If diagnosis code B1433 is set in the combination
meter,
always diagnose the CAN bus lines.
|
OPERATION
- 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
This diagnosis code is set if there
is abnormal resistance between the input terminals
of the side-airbag module (LH) (squib).
PROBABLE CAUSES
- Damaged wiring harnesses or connectors
- Short to the power supply in the side-airbag module (LH) (squib)
harness
- Malfunction of the SRS-ECU
|
|
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 lines (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 side-airbag module (LH) (M.U.T.-III diagnosis
code).
|
|
|
(1)Disconnect the negative battery terminal.
|
|
(2)Disconnect the side-airbag module (LH)
connector D-22.
|
|
(3)Connect special tool dummy resistor
(MB991865) to special tool resistor harness (MB991866).
(4)
| caution |
Do not insert a test probe into the
terminal from its front side directly, as the connector contact pressure
may be weakened.
|
Insert special tool MB991866 into the D-22 harness side connector
by backprobing.
(5)Connect the negative battery terminal.
(6)Erase
the diagnosis code memory, and check the diagnosis code.
Q.
Is diagnosis code B1433 set?
Go to Step 4.
Replace the frame assembly of the
front seat (LH) (Refer to GROUP 52A, Front Seat ).
|
|
|
STEP 4. Check the side-airbag module (RH) circuit. Voltage measurement
at the SRS-ECU connector C-120.
|
|
(1)Disconnect SRS-ECU connector C-120.
|
|
(2)
| danger |
To prevent the air bag from deploying
unintentionally, disconnect the side-airbag module
(LH) connector D-22 to short the squib circuit.
|
Disconnect left hand side-airbag module (LH) connector
D-22.
(3)Turn the ignition switch to the "ON" position.
|
|
(4)
| caution |
Do not insert a test probe into the terminal from
its front side directly, as the connector
contact pressure may be weakened.
|
Measure the voltage between C-120 harness side connector terminals
9, 10 and body earth.
OK: 0 V
Q.
Is the check result normal?
Go to Step 5.
Repair the harness wires between
SRS-ECU connector C-120 (terminal No.9 and 10)
and side-airbag module (LH) connector D-22 (terminal No.1 and
2).
|
|
|
STEP 5. Check whether the diagnosis code is reset.
|
|
|
Q.
Is diagnosis code B1433 set?
|
|
|
Replace the SRS-ECU (Refer to ).
|
|
|
|
|
|
An
intermittent malfunction is suspected (Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service
Points ).
|
|
|
|