Code No.B1442: Curtain air bag squib (RH) (earth side) short-circuited














caution If diagnosis code B1442 is set in the SRS-ECU, always diagnose the CAN main bus line.

OPERATION



DIAGNOSIS CODE SET CONDITIONS



PROBABLE CAUSES



  • Damaged wiring harnesses or connectors
  • Short to the earth in the curtain air bag module (RH) (squib) harness
  • 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 curtain air bag module (RH).
(1)Disconnect the negative battery terminal.

(2)Disconnect curtain air bag module connector E-04. Use a flat-tipped screwdriver to unlock the locking button at the curtain air bag module connector by withdrawing it toward you in two stages, and then disconnect the connector.

(3)Connect special tool dummy resistor (MB991865) to special tool resistor harness (MB991884).
(4)Connect special tool (MB991884) to the E-04 curtain air bag module connector.
(5)Connect the negative battery terminal.
(6)Erase the diagnosis code from memory, and check the diagnosis code.

Q. Is diagnosis code B1442 set?

Go to Step 4.

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

STEP 4. Check the curtain air bag module (RH) circuit. Resistance measurement at the SRS-ECU connector D-23.
(1)Disconnect the negative battery terminal.
(2)Disconnect SRS-ECU connector D-23.
danger To prevent the air bag from deploying unintentionally, disconnect the curtain air bag module (RH) connector E-04 to short the squib circuit.

(3)Disconnect curtain air bag module connector E-04. Use a flat-tipped screwdriver to unlock the locking button at the curtain air bag module connector by withdrawing it toward you in two stages, and then disconnect the connector.

(4)
caution Insert an insulator such as a cable tie to a depth of 4 mm or more, otherwise the short spring will not be released.
Insert a cable tie [3 mm wide, 0.5 mm thick] between terminals 61and 62, and the short spring to release the short spring.
(5)
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 D-23 harness side connector terminals 61, 62 and body earth.
OK: Open circuit

Q. Is the check result normal?

Go to Step 5.

Repair the harness wire between SRS-ECU connector D-23 (terminal No.61and 62) and curtain air bag module (RH) connector E-04 (terminal No.1 and 2).

STEP 5. Check whether the diagnosis code is reset.

Q. Is diagnosis code B1442 set?
Replace the SRS-ECU (Refer to ).
An intermittent malfunction is suspected (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).