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DLC Circuit Troubleshooting (2017 2018, Without CAN Gateway)

DLC Circuit Troubleshooting 

NOTE:

If you suspect the HDS or the HDS DLC cable may be the source of the communication problem, verify that they are working properly by connecting them to a known-good, similar vehicle and system, and checking for communication problems.

  1. HDS communication check

    -1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Connect the HDS to the DLC.

    NOTE:

    Make sure the HDS is properly connected to the DLC.

    - 3. Turn the vehicle to the ON mode, and turn on the HDS.

    Does the HDS identify the vehicle?

    YES 

    Go to step 2.

    NO 

    Go to step 12.

  2. Determine possible failure area (PGM-FI system, other systems)

    -1. Check for Pending or Confirmed DTCs in the PGM-FI system with the HDS.

    DTC Description Confirmed DTC Pending DTC
         

    Are any Pending or Confirmed DTCs indicated?

    YES 

    Go to the indicated DTC's troubleshooting.

    NO 

    If the HDS does not communicate with the PCM, go to step 3.

    NO 

    If the HDS does not communicate with the SRS, go to step 5.

    NO 

    If the HDS does not communicate with the EPS system, go to step 6.

    NO 

    If the HDS does not communicate with the ONE PUSH START system, go to step 7.

    NO 

    If the HDS does not communicate with the BODY ELECTRICAL system, go to step 8.

  3. Open wire check (F-CAN A_H line)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Jump the SCS line with the HDS, and wait more than 1 minute.

    - 3. Disconnect the following connectors.

    CAN gateway 24P connector
    PCM connector A (51P)

    - 4. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      PCM connector A (51P): disconnected
    Test point 1 CAN gateway 24P connector (female terminals) No. 14:
    Test point 2 PCM connector A (51P) No. 9 - Refer to: PCM Connector for Inputs and Outputs (2017 2018 2019 2020),
    GHH324723Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN A_H wire is OK. Go to step 4.

    NO 

    Repair an open in the F-CAN A_H wire between the PCM (A9) and the CAN gateway.

  4. Open wire check (F-CAN A_L line)

    -1. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      PCM connector A (51P): disconnected
    Test point 1 CAN gateway 24P connector (female terminals) No. 15:
    Test point 2 PCM connector A (51P) No. 10 - Refer to: PCM Connector for Inputs and Outputs (2017 2018 2019 2020),
    GHH324725Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN A_L wire is OK. Check for poor connections or loose terminals at the CAN gateway and the PCM. Go to the PCM power and ground circuit troubleshooting - Refer to: PCM Power and Ground Circuit Troubleshooting (2017 2018 2019 2020) .

    NO 

    Repair an open in the F-CAN A_L wire between the PCM (A10) and the CAN gateway.

  5. SRS check

    -1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Turn the vehicle to the ON mode, and watch the SRS indicator.

    Does the SRS indicator come on and go off?

    YES 

    The SRS is OK. Go to step 9.

    NO 

    Go to the symptom troubleshooting for SRS indicator stays on, but no DTCs are stored, or cannot be read - Refer to: SRS Symptom Troubleshooting - SRS indicator stays on, but no DTCs are stored, or cannot be read (2017 2018 2019 2020), .

  6. EPS system check

    -1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Start the engine, and watch the EPS indicator.

    Does the EPS indicator come on and go off?

    YES 

    The EPS system is OK. Go to step 9.

    NO 

    Go to the EPS symptom troubleshooting for EPS indicator does not go off, and no DTCs are stored - Refer to: EPS Symptom Troubleshooting - EPS indicator does not go off, and no DTCs are stored (2017 2018), or EPS Symptom Troubleshooting - EPS indicator does not go off, and no DTCs are stored (2017 2018), or EPS Symptom Troubleshooting - EPS indicator does not go off, and no DTCs are stored (2017 2018), .

  7. Keyless access system check

    -1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Turn the vehicle to the ON mode, and watch the keyless access indicator.

    Does the keyless access indicator stay on?

    YES 

    Go to the keyless access system general troubleshooting information - Refer to: Keyless Access System Symptom Troubleshooting Information (2016 2017 2018 2019 2020) .

    NO 

    The keyless access system is OK. Go to step 9.

  8. Body electrical system check

    -1. Do the gauge self-diagnostic function.

    - 2. Check the gauge display.

    Is B-CAN------ERROR indicated?

    YES 

    Go to the indicated DTC's troubleshooting.

    NO 

    The body electrical system is OK. Go to step 9.

  9. Open wire check (K-LINE line or P-LINE line)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Disconnect the HDS from the DLC.

    - 3. Disconnect the control unit (s) on the K-LINE or P-LINE that does not communicate.

    K-LINE 

    • Audio-navigation unit connector A (24P)
    • EPS control unit connector A (11P)
    • ANC/active sound control unit 20P connector
    • Keyless access/TPMS control unit connector C (20P)
    • Under-dash fuse/relay box connector G (16P)

    P-LINE 

    • Keyless access/TPMS control unit connector C (20P)
    • SRS unit connector A (39P)

    - 4. Check for continuity between DLC (16P) No. 7 and these connector terminals (K-LINE line), or DLC (16P) No. 15 and these connector terminals (P-LINE line):

    K-LINE 

    Connector Terminal
    ANC/active sound control unit 20P connector No. 14
    EPS control unit connector A (11P) No. 7
    Audio-navigation unit connector A (24P) No. 13
    Keyless access/TPMS control unit connector C (20P) No. 4
    Driver's under-dash fuse/relay box connector G (16P) No. 13

    P-LINE 

    Connector Terminal
    Keyless access/TPMS control unit connector C (20P) No. 6
    SRS unit connector A (39P) No. 33
    GHH324726Courtesy of HONDA, U.S.A., INC.

    Is there continuity between the DLC and the terminals in the chart?

    YES 

    Go to step 10.

    NO 

    Repair an open in the wire between the DLC (K-LINE wire or P-LINE wire) and the appropriate connector.

  10. Determine possible failure area (short in K-LINE line or P-LINE line, others)

    -1. Reconnect all connectors.

    - 2. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
    Test point 1 DLC (16P) (female terminals) No. 7 and No. 15:
    Test point 2 Body ground
    GHH324728Courtesy of HONDA, U.S.A., INC.

    Is there any voltage?

    YES 

    Go to step 12.

    NO 

    Go to step 11.

  11. Shorted wire check (K-LINE line, P-LINE line)

    -1. Continue to measure the voltage between DLC (16P) No. 7 and body ground (K-LINE line), or DLC (16P) No. 15 and body ground (P-LINE line) while disconnecting these parts, one at a time:

    NOTE:

    Turn the vehicle to the OFF (LOCK) mode before disconnecting the connector, and turn the vehicle to the ON mode before measuring the voltage.

    K-LINE 

    • Audio-navigation unit connector A (24P)
    • EPS control unit connector A (11P)
    • ANC/active sound control unit 20P connector
    • Keyless access/TPMS control unit connector C (20P)
    • Under-dash fuse/relay box connector G (16P)

    P-LINE 

    • Keyless access/TPMS control unit connector C (20P)
    • SRS unit connector A (39P)

    Does continuity go away when one of the above components is disconnected?

    YES 

    Replace the part that any voltage was detected when it was disconnected.

    NO 

    Repair a short in the wire between DLC (16P) No. 7 (K-LINE) and the ANC/active sound control unit, the EPS control unit, the audio-navigation unit, the keyless access/TPMS control unit, the driver's under-dash fuse/relay box (MICU), or DLC (16P) No. 15 (P-LINE) and the keyless access/TPMS control unit or the SRS unit.

  12. Body electrical system (B-CAN) check

    -1. Do the gauge self-diagnostic function.

    - 2. Check for gauge control module DTCs without the HDS.

    Is DTC U0029 and/or U0100 indicated?

    YES 

    Go to the PCM power and ground circuit troubleshooting - Refer to: PCM Connector for Inputs and Outputs (2017 2018 2019 2020) .

    NO 

    Go to step 13.

  13. Open wire check (+B BACK UP line)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Disconnect the HDS from the DLC.

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

    Test condition Vehicle OFF (LOCK) mode
    Test point 1 DLC (16P) (female terminals) No. 16:
    Test point 2 Body ground
    GHH324730Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The +B BACK UP wire is OK. Go to step 14.

    NO 

    Repair an open in the +B BACK UP wire between DLC (16P) No. 16 and the No. C16 (10 A) fuse in the under-hood fuse/relay box.

  14. Open wire check (PGND line)

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

    Test condition Vehicle OFF (LOCK) mode
    Test point 1 DLC (16P) (female terminals) No. 4:
    Test point 2 DLC (16P) (female terminals) No. 16:
    GHH324733Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The PGND wire is OK. Go to step 15.

    NO 

    Repair an open in the PGND wire between DLC (16P) No. 4 and G501.

  15. Open wire check (IG1 OPTION (without auto idle stop system), IG1 MICU (DC/DC) (with auto idle stop system) line)

    -1. Disconnect the following connector.

    CAN gateway 24P connector

    - 2. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
      CAN gateway 24P connector: disconnected
    Test point 1 CAN gateway 24P connector (female terminals) No. 21:
    Test point 2 Body ground
    GHH324735Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The IG1 OPTION (without auto idle stop system), IG1 MICU (DC/DC) (with auto idle stop system) wire is OK. Go to step 16.

    NO 

    Repair an open in theIG1 OPTION (without auto idle stop system), IG1 MICU (DC/DC) (with auto idle stop system) wire between the CAN gateway and DC-DC converter IG1 relay 2 in the auxiliary under-dash fuse/relay box.

  16. Open wire check (GND lines)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
    Test point 1 CAN gateway 24P connector (female terminals) No. 18 and No. 19:
    Test point 2 Body ground
    GHH324737Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The GND wires are OK. Go to step 17.

    NO 

    Repair an open in the GND wire (s) between the CAN gateway and G504.

  17. Open wire check (DIAG-CAN_H line)

    -1. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
    Test point 1 CAN gateway 24P connector (female terminals) No. 3:
    Test point 2 DLC (16P) (female terminals) No. 6:
    GHH324740Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The DIAG-CAN_H wire is not open. Go to step 18.

    NO 

    Repair an open in the DIAG-CAN_H wire between the CAN gateway and DLC (16P) No. 6.

  18. Open wire check (DIAG-CAN_L line)

    -1. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
    Test point 1 CAN gateway 24P connector (female terminals) No. 2:
    Test point 2 DLC (16P) (female terminals) No. 14:
    GHH324743Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The DIAG-CAN_L wire is not open. Go to step 19.

    NO 

    Repair an open in the DIAG-CAN_L wire between the CAN gateway and DLC (16P) No. 14.

  19. Shorted wire check (DIAG-CAN_H line)

    -1. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
    Test point 1 DLC (16P) (female terminals) No. 6:
    Test point 2 Body ground
    GHH324745Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The DIAG-CAN_H wire is not shorted to ground. Go to step 20.

    NO 

    Repair a short in the DIAG-CAN_H wire between the CAN gateway and DLC (16P) No. 6.

  20. Shorted wire check (DIAG-CAN_L line)

    -1. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
    Test point 1 DLC (16P) (female terminals) No. 14:
    Test point 2 Body ground
    GHH324747Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The DIAG-CAN_L wire is not shorted to ground. Go to step 21.

    NO 

    Repair a short in the DIAG-CAN_L wire between the CAN gateway and DLC (16P) No. 14.

  21. Shorted wire check (DIAG-CAN_H line to DIAG-CAN_L line)

    -1. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
    Test point 1 DLC (16P) (female terminals) No. 6:
    Test point 2 DLC (16P) (female terminals) No. 14:
    GHH324750Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the DIAG-CAN_H wire to the DIAG-CAN_L wire between DLC (16P) No. 6 and No. 14.

    NO 

    The DIAG-CAN_H wire and DIAG-CAN_L wire are OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or substitute a known-good CAN gateway .

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