Code No.B1453: Curtain air bag module (LH) (squib) system (short-circuited to the power supply)












OPERATION



TROUBLE JUDGEMENT



PROBABLE CAUSES



  • Damaged wiring harness and connector
  • Curtain air bag module (squib) harness shorted to power supply
  • Malfunction of SRS-ECU

DIAGNOSIS PROCEDURE

STEP1. Diagnosis check by dummy resistor connection.
(1)Check that the negative auxiliary battery terminal is disconnected. If the negative auxiliary battery terminal is connected, disconnect it.

(2)Use the flat-tipped screwdriver to pull out the locking button of C-10 harness side connector to the direction of the arrow. After releasing the lock, disconnect the connector.

(3)Connect the dummy resistor (Special tool: MB991865) to the resistor harness (Special tool: MB991884).
(4)Connect special tool (MB991884) to the C-10 harness side connector.
(5)Connect the negative auxiliary battery terminal.
(6)After erasing the diagnosis code memory, check the diagnosis code again.
(7)Disconnect the negative auxiliary battery terminal.

Q. Is diagnosis code B1453 set?

Go to Step 2

Replace the curtain air bag module (LH) (Refer to ).

STEP 2. Voltage measurement at the B-113 SRS-ECU connector.
(1)Check that the negative auxiliary battery terminal is disconnected. If the negative auxiliary battery terminal is connected, disconnect it.
(2)Disconnect the B-113. SRS-ECU connector.

(3)
danger To release SRS-ECU wiring harness side connector short spring in the following operations, disconnect air bag module connector in advance, and keep the squib circuit shorted.
Use the flat-tipped screwdriver to pull out the locking button of C-10 harness side connector to the direction of the arrow. After releasing the lock, disconnect the connector.

(4)
caution The short spring may not be released due to the insufficient insertion. Therefore, insert the insulator for 4 mm or more.
Insert an insulator (width: 3 mm, thickness: 0.5 mm) such as cable tie between the terminal 1/2 and the short spring, and release the short spring.
(5)Connect the negative auxiliary battery terminal.
(6)Electric motor switch to the "ON" position.
(7)
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 the B-113 harness side connector terminal No. 1/2 and the body earth.
OK: 1 V or less
(8)Disconnect the negative auxiliary battery terminal.

Q. Is the check result normal?

Go to Step 3

Repair the wiring harness.

STEP 3. Check whether the diagnosis code is reset.

Q. Is diagnosis code B1453 set?
Replace the SRS-ECU (Refer to ).
An intermittent malfunction is suspected (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).