Code
No.B1461: Seat belt pre-tensioner squib (RH) open-circuited
M15204000195ENG0000010000
caution
If diagnosis code B1461 is set in the SRS-ECU, always diagnose
the CAN main bus line.
OPERATION
The SRS-ECU judges how severe a collision is by detecting signals from the front impact
sensors and the front air bag analogue G-sensor. If the impact is over a predetermined level,
the SRS-ECU sends an ignition signal. At this time, if the front air bag safing G-sensor is
on, the pre-tensioner will deploy.
DIAGNOSIS CODE SET CONDITIONS
This diagnosis code is set if there is abnormal resistance between the input terminals
of the seat belt pre-tensioner (RH) (squib).
PROBABLE CAUSES
Open circuit in the seat belt pre-tensioner (RH) (squib) circuit
Improper connector contact
Malfunction of the SRS-ECU
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 seat belt pre-tensioner (RH) (M.U.T.-III
diagnosis code).
(1)Disconnect the negative battery terminal.
(2)Disconnect seat belt pre-tensioner connector (RH) E-30.
(3)Connect special tool dummy resistor (MB991865) to special tool resistor harness (MB991866). (4)Connect special tool MB991866 to the E-30 harness side connector. (5)Connect the negative battery terminal. (6)Erase the diagnosis code from memory, and then check the diagnosis code.
Q.
Is diagnosis code B1461 set?
Go to Step 4. Replace the seat belt with pre-tensioner (RH) (Refer to ).
STEP 4. Resistance measurement between SRS-ECU connector
D-23 (terminal No.59 and 60) and the seat belt pre-tensioner (RH) connector E-30 (terminal No.2
and 1).
(1)Disconnect the negative battery terminal.
(2)Disconnect SRS-ECU connector D-23 and seat belt pre-tensioner (RH) connector E-30.
(3)Connect E-30 harness side connector to special tool resistor harness (MB991884).
(4)
caution
Do not insert a test probe into the terminal from its front side directly, as the connector
contact pressure may be weakened.
Check for continuity between the following terminals.
SRS-ECU connector D-23 (terminal No.59) and the special tool (terminal No.1)
SRS-ECU connector D-23 (terminal No.60) and the special tool (terminal No.2)
OK: Continuity (Less than 2 Ω)
Q.
Are the check results normal?
Go to Step 5. Repair the harness wires between SRS-ECU connector D-23 (terminal No.59 and 60)
and seat belt pre-tensioner (RH) connector E-30 (terminal No.2 and 1).
STEP 5. Check whether the diagnosis code is reset.
Q.
Is diagnosis code B1461 set?
Replace the SRS-ECU (Refer to ).
An intermittent malfunction is suspected (Refer to GROUP 00, How to Cope with
Intermittent Malfunction ).
)
Go to Step 2.
Repair the CAN bus line (Refer to GROUP 54D, Diagnosis 
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