LEMON Manuals: Even more car manuals for everyone
Home >> Honda >> 2021 >> Ridgeline RTL, AWD >> Repair and Diagnosis >> Accessories & Equipment >> Communication Devices >> Network Communication - Testing & Troubleshooting >> Troubleshooting >> DLC Circuit Troubleshooting (Without CAN Gateway)

DLC Circuit Troubleshooting (Without CAN Gateway)

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  11.

  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 SRS, go to step 3.

    NO 

    If the HDS does not communicate with the VSA system, go to step  4.

    NO 

    If the HDS does not communicate with the IMMOBI (immobilizer) system, go to step  5.

    NO 

    If the HDS does not communicate with the ONE PUSH START system, go to step  6.

    NO 

    If the HDS does not communicate with the BODY ELECTRICAL system, go to step  7.

  3. 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  8.

    NO 

    Go to the symptom troubleshooting for SRS indicator stays on, but no DTCs are stored, or cannot be read .

  4. VSA system check

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

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

    Does the VSA indicator come on and go off?

    YES 

    The VSA system is OK. Go to step  8.

    NO 

    Go to the symptom troubleshooting for ABS indicator, brake system indicator (red), VSA indicator, and brake system indicator (amber) do not go off .

  5. Immobilizer system check

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

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

    Does the immobilizer indicator stay on or flash?

    YES 

    Go to the immobilizer system troubleshooting .

    NO 

    The immobilizer system is OK. Go to step 8. 8

  6. 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 and the immobilizer indicator.

    Does the keyless access indicator stay on or the immobilizer indicator stay on or flash?

    YES 

    Go to the keyless access system symptom troubleshooting information .

    NO 

    The keyless access system is OK. Go to step  8.

  7. Body electrical system check

    -1. Do the gauge self-diagnostic function .

    -2. Check the gauge display.

    Is Error 2 indicated?

    YES 

    Go to the indicated DTC's troubleshooting.

    NO 

    The body electrical system is OK. Go to step 8.

  8. Open wire check (K-LINE line or L-LINE line)

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

    -2. Disconnect the HDS from the DLC.

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

    K-LINE 

    • VSA modulator-control unit 38P connector
    • Audio-navigation unit connector A (24P) (with navigation)
    • Audio unit connector A (24P) (with display audio)
    • Audio unit connector A (24P) (with color audio)
    • ANC/active sound control unit 20P connector
    • Keyless access/TPMS control unit connector C (20P)
    • Under-dash fuse/relay box connector R (16P)

    L-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 (L-LINE line):

    K-LINE 

    Connector Terminal
    VSA modulator-control unit 38P connector No. 33
    Audio-navigation unit connector A (24P) (with navigation) No. 13
    Audio unit connector A (24P) (with display audio) No. 13
    Audio unit connector A (24P) (with color audio) No. 13
    ANC/active sound control unit 20P connector No. 14
    Keyless access/TPMS control unit connector C (20P) No. 4
    Under-dash fuse/relay box connector R (16P) No. 9

    L-LINE 

    Connector Terminal
    Keyless access/TPMS control unit connector C (20P) No. 6
    SRS unit connector A (39P) No. 33

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

    YES 

    Go to step 9.

    NO 

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

  9. Determine possible failure area (short in K-LINE line or L-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
    GHH458675Courtesy of HONDA, U.S.A., INC.

    Is there any voltage?

    YES 

    Go to step  11.

    NO 

    Go to step 10.

  10. Shorted wire check (K-LINE line, L-LINE line):

    Continue to measure the voltage between DLC (16P) No. 7 and body ground (K-LINE line), or DLC (16P) No. 15 and body ground (L-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 

    • VSA modulator-control unit 38P connector
    • Audio-navigation unit connector A (24P) (with navigation)
    • Audio unit connector A (24P) (with display audio)
    • Audio unit connector A (24P) (with color audio)
    • ANC/active sound control unit 20P connector
    • Keyless access/TPMS control unit connector C (20P)
    • Under-dash fuse/relay box connector R (16P)

    L-LINE 

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

    Does voltage come back 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 VSA modulator-control unit, the audio-navigation unit, the audio unit, the ANC/active sound control unit, the keyless access/TPMS control unit, the front passenger's weight sensor unit, or the under-dash fuse/relay box (MICU), or DLC (16P) No. 15 (L-LINE) and the keyless access/TPMS control unit or the SRS unit.

  11. 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 .

    NO 

    Go to step 12.

  12. 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
    GHH458677Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The +B BACK UP wire is OK. Go to step 13.

    NO 

    Repair an open in the +B BACKUP wire between DLC (16P) No. 16 and the No. A26 (10 A) fuse in the under-hood fuse/relay box.

  13. Open wire check (PGND line)

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

    Test condition Vehicle OFF (LOCK) mode
    Test point 1 DLC (16P) (female terminals) No. 4:
    Test point 2 Body ground
    GHH458679Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The PGND wire is OK. Go to step 14.

    NO 

    Repair an open in the PGND wire between DLC (16P) No. 4 and G402.

  14. Open wire check (F-CAN_H line)

    -1. Disconnect the following connector.

    PCM connector A (51P)

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

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
    Test point 1 PCM connector A (51P) No. 9
    Test point 2 DLC (16P) (female terminals) No. 6:
    GHH458681Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN_H wire is not open. Go to step 15.

    NO 

    Repair an open in the F-CAN_H wire between the PCM (A9) and DLC (16P) No. 6.

  15. Open wire check (F-CAN_L line)

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

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (51P): disconnected
    Test point 1 PCM connector A (51P) No. 10
    Test point 2 DLC (16P) (female terminals) No. 14:
    GHH458683Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN_L wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or substitute a known-good PCM .

    NO 

    Repair an open in the F-CAN_L wire between the PCM (A10) and DLC (16P) No. 14.