Posted in Mitsubishi Colt

B1403 – Driver’s air bag module (squib) system (short-circuited to power supply) MMC Colt

 Posted by  Posted on September 27, 2020

OPERATION

  • The SRS-ECU judges how severe a collision is by detecting signals from 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 SRS air bag will inflate.
  • The ignition signal is input to the air bag module via the clock spring to inflate the air bag.

    • DIAGNOSIS CODE SET CONDITIONS

    PROBABLE CAUSES

  • Malfunction of the clock spring
  • Damaged harness wires and connectors
  • Short to the power supply in the driver’s air bag module (squib) harness
  • Malfunction of the SRS-ECU

    • DIAGNOSIS PROCEDURE

    STEP 1. M.U.T.-III CAN bus diagnostics.

    Q. Is the CAN bus line found to be normal?

    STEP 2. Check whether the diagnosis code is reset.

    Q. Is the diagnosis code set?

    STEP 3. Check the driver’s air bag module (M.U.T.-III diagnosis code).

    Q. Is diagnosis code B1403 set?

    STEP 4. Check the clock spring (M.U.T.-III diagnosis code).

    Q. Is diagnosis code B1403 set?

    STEP 5. Voltage measurement at the SRS-ECU connector B-109.

    Q. Is the check result normal?

    STEP 6. Check whether the diagnosis code is reset.

    Q. Is diagnosis code B1403 set?

    Author: admin