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DTC B2964 (93)

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DTC B2964 or DTC indicator 93  : Climate control unit lost communication with Front PANEL

DTC Description DTC
B2964 Climate control unit lost communication with Front PANEL  

DTCs (AC)

  1. Problem verification

    -1. Clear the DTCs with the HDS.

    -2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

    -3. Do the Self-Diagnostic Function with the HDS or the climate control unit .

    -4. Check for DTCs.

    DTC Description DTC
    B2964 Climate control unit lost communication with Front PANEL  

    Is DTC B2964 or 93 indicated?

    YES 

    The failure is duplicated. Go to step 2.

    NO 

    Intermittent failure. Check for loose wires or poor connections on the climate control panel circuit.

  2. Fuse check

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

    -2. Check the following fuse.

    Fuse No. B14

    Is the fuse OK?

    YES 

    Go to step 3.

    NO 

    Replace the fuse, and recheck. If the fuse blows again, repair a short in the No. B14 fuse circuit.

  3. Determine possible failure area (BUS-DATA line, others)

    -1. Disconnect the following connector.

    Climate control panel 12P connector

    -2. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
    Climate control panel 12P connector: disconnected
    Test point 1 Climate control panel 12P connector (female terminals) No. 1:
    Test point 2 Climate control panel 12P connector (female terminals) No. 4:
    GHH396072Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    Go to step 4.

    NO 

    Go to step 7.

  4. Shorted wire check (BUS-DATA line)

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

    -2. Disconnect the following connector.

    Climate control unit connector A (32P)

    -3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
    Climate control unit connector A (32P): disconnected
    Climate control panel 12P connector: disconnected
    Test point 1 Climate control unit connector A (32P) No. 29
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short to ground in the BUS-DATA wire.

    NO 

    The BUS-DATA wire is not shorted. Go to step 5.

  5. Open wire check (BUS-DATA line)

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

    Test condition Vehicle OFF (LOCK) mode
    Climate control unit connector A (32P): disconnected
    Climate control panel 12P connector: disconnected
    Test point 1 Climate control unit connector A (32P) No. 29
    Test point 2 Climate control panel 12P connector (female terminals) No. 9:
    GHH396074Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The BUS-DATA wire is OK. Go to step 6.

    NO 

    Repair an open in the BUS-DATA wire.

  6. Climate control panel check

    -1. Reconnect the following connector.

    Climate control unit connector A (32P)

    -2. Substitute a known-good climate control panel .

    -3. Clear the DTCs with the HDS.

    -4. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

    -5. Do the Self-Diagnostic Function with the HDS or the climate control unit .

    -6. Check for DTCs.

    DTC Description DTC
    B2964 Climate control unit lost communication with Front PANEL  

    Is DTC B2964 or 93 indicated?

    YES 

    Replace the climate control unit .

    NO 

    Replace the original climate control panel .

  7. Open wire check (IG2 A/C line)

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

    Test condition Vehicle ON mode
    Climate control panel 12P connector: disconnected
    Test point 1 Climate control panel 12P connector (female terminals) No. 1:
    Test point 2 Body ground
    GHH396076Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    Check for an open in the GND wire. If the wire is OK, check for poor ground at G504.

    NO 

    Repair an open in the IG2 A/C wire.