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Home >> Acura >> 2021 >> ILX >> Repair and Diagnosis >> Restraints >> Air Bag, SRS >> Supplemental Restraint System (SRS) - DTC Diagnostics (3 Of 3) (Except Hybrid) >> DTC Troubleshooting >> SRS DTC 41-1x

SRS DTC 41-1x

DTC 41-1x ("x" can be 0 thru 9 or A thru F)  : No Signal From the Left Front Impact Sensor

Special Tools Required 

SRS Inflator Simulator 07SAZ-TB4011A 

SRS Simulator Lead L 070AZ-SNAA300 

NOTE:
DTC Description DTC
   

DTC (SRS)

  1. Problem verification

    -1. Clear the DTCs with the HDS .

    -2. Press the engine start/stop button to select the ON mode, then wait for 10 seconds.

    -3. Check for DTCs with the HDS .

    DTC Description DTC
       

    Is DTC 41-1x indicated?

    YES 

    The failure is duplicated. Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures . If another DTC is indicated, troubleshoot the DTC.

  2. Connector connection check

    -1. Press the engine start/stop button to select the OFF mode.

    -2. Check the following connector connections.

    SRS unit connector A (39P)
    Left front impact sensor 2P connector (on the engine compartment wire harness)
    Connector between the SRS unit and the left front impact sensor

    Are the connectors OK?

    YES 

    Go to step 4.

    NO 

    Go to step 3.

  3. System check

    -1. Repair the poor connector connections whichever was the cause of the problem in step 2.

    -2. Clear the DTCs with the HDS .

    -3. Press the engine start/stop button to select the ON mode, then wait for 10 seconds.

    -4. Check for DTCs with the HDS .

    DTC Description DTC
       

    Is DTC 41-1x indicated?

    YES 

    Press the engine start/stop button to select the OFF mode, then go to step 4.

    NO 

    The system is OK at this time.

  4. Shorted wire check (LFS+ line to LFS- line)

    -1. Disconnect the negative cable from the battery, then wait at least 3 minutes.

    -2. Disconnect the following connectors.

    SRS unit connector A (39P)
    Left front impact sensor 2P connector (on the engine compartment wire harness)

    -3. Measure the resistance between test points 1 and 2.

    Test condition OFF mode
    SRS unit connector A (39P): disconnected
    Left front impact sensor 2P connector (on the engine compartment wire harness): disconnected
    Test circuit LFS+, LFS-
    Test point 1 SRS unit connector A (39P) No. 28
    Test point 2 SRS unit connector A (39P) No. 29
    GHH475485Courtesy of HONDA, U.S.A., INC.

    Is there an open circuit, or at least 1 MΩ?

    YES 

    The LFS+ and LFS- wires are not shorted. Go to step 5.

    NO 

    Short to another wire in the engine compartment wire harness or the dashboard wire harness; replace the faulty harness, then clear the DTC.

  5. Shorted wire check (LFS+, LFS- lines)

    -1. Measure the resistance between test points 1 and 2.

    Test condition OFF mode
    SRS unit connector A (39P): disconnected
    Left front impact sensor 2P connector (on the engine compartment wire harness): disconnected
    Test circuit LFS+
    Test point 1 SRS unit connector A (39P) No. 28
    Test point 2 Body ground
    Test circuit LFS-
    Test point 1 SRS unit connector A (39P) No. 29
    Test point 2 Body ground
    GHH475486Courtesy of HONDA, U.S.A., INC.

    Is there an open circuit, or at least 1 MΩ?

    YES 

    The LFS+ and LFS- wires are not shorted. Go to step 6.

    NO 

    Short to ground in the engine compartment wire harness or the dashboard wire harness; replace the faulty harness, then clear the DTC.

  6. Shorted wire check (LFS+, LFS- lines to power)

    -1. Reconnect the negative cable to the battery.

    -2. Press the engine start/stop button to select the ON mode.

    -3. Measure the voltage between test points 1 and 2.

    Test condition ON mode
    SRS unit connector A (39P): disconnected
    Left front impact sensor 2P connector (on the engine compartment wire harness): disconnected
    Test circuit LFS+
    Test point 1 SRS unit connector A (39P) No. 28
    Test point 2 Body ground
    Test circuit LFS-
    Test point 1 SRS unit connector A (39P) No. 29
    Test point 2 Body ground
    GHH475487Courtesy of HONDA, U.S.A., INC.

    Is there 0.2 V or less?

    YES 

    The LFS+ and LFS- wires are not shorted to power. Go to step 7.

    NO 

    Short to power in the engine compartment wire harness or the dashboard wire harness; replace the faulty harness, then clear the DTC.

  7. Open wire check (LFS+, LFS- lines)

    -1. Press the engine start/stop button to select the OFF mode.

    -2. Connect the black terminal (A) of SRS simulator lead L to the SRS inflator simulator (jumper connector), then connect SRS simulator lead L to the left front impact sensor 2P connector (B) on the engine compartment wire harness.

    GHH475488Courtesy of HONDA, U.S.A., INC.

    -3. Measure the resistance between test points 1 and 2.

    Test condition OFF mode
    SRS unit connector A (39P): disconnected
    Left front impact sensor 2P connector (on the engine compartment wire harness): disconnected
    Left front impact sensor 2P connector (on the engine compartment wire harness): connected to SRS simulator lead L
    Test circuit LFS+, LFS-
    Test point 1 SRS unit connector A (39P) No. 28
    Test point 2 SRS unit connector A (39P) No. 29
    GHH475489Courtesy of HONDA, U.S.A., INC.

    Is there 1.0 Ω or less?

    YES 

    The LFS+ and LFS- wires are OK. Replace the left front impact sensor , then clear the DTC, and retest. If the DTC is still present, replace the SRS unit .

    NO 

    Open in the engine compartment wire harness or the dashboard wire harness; replace the faulty harness, then clear the DTC.