DTC B1275, B1276, B1277, B1278

2020 Honda Civic Sport, 4D Hatchback, Standard TransSECTION DTC B1275, B1276, B1277, B1278

DTC B1275  : Headlight OFF Position Circuit Malfunction

DTC B1276  : Headlight Switch Parking Position Circuit Malfunction

DTC B1277  : Headlight AUTO Position Circuit Malfunction

DTC B1278  : Headlight ON Position Circuit Malfunction

NOTE:  If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .

DTC Description DTC
B1275 Headlight OFF Position Circuit Malfunction  
B1276 Headlight Switch Parking Position Circuit Malfunction  
DTC Description DTC
B1277 Headlight AUTO Position Circuit Malfunction  
B1278 Headlight ON Position Circuit Malfunction  

DTC (Body Control Module)

  1. Problem verification

    -1. Check the parameter(s) below with the HDS.

    When the combination light switch is turned OFF 

    Signal Threshold Current conditions
    Values Unit Values Unit
    Headlight Switch (OFF) ON      
    Headlight Switch (PARKING) OFF      
    Headlight Switch (AUTO) OFF      
    Headlight Switch (HEADLIGHT) OFF      

    When the combination light switch is turned to POSITION (PARKING) 

    Signal Threshold Current conditions
    Values Unit Values Unit
    Headlight Switch (OFF) OFF      
    Headlight Switch (PARKING) ON      
    Headlight Switch (AUTO) OFF      
    Headlight Switch (HEADLIGHT) OFF      

    When the combination light switch is turned to AUTO 

    Signal Threshold Current conditions
    Values Unit Values Unit
    Headlight Switch (OFF) OFF      
    Headlight Switch (PARKING) OFF      
    Headlight Switch (AUTO) ON      
    Headlight Switch (HEADLIGHT) OFF      

    When the combination light switch is turned ON (HEADLIGHT) 

    Signal Threshold Current conditions
    Values Unit Values Unit
    Headlight Switch (OFF) OFF      
    Headlight Switch (PARKING) ON      
    Headlight Switch (AUTO) OFF      
    Headlight Switch (HEADLIGHT) ON      

    Are all data list values correct?

    YES 

    Intermittent failure, the system is OK at this time. Check for loose or poor connections.

    NO 

    Go to step 2.

  2. Exterior lights system check

    -1. Check the parameter(s) below with the HDS.

    Cycle through all switch selections 

    Signal Current conditions
    Values Unit
    Headlight Switch (OFF)    
    Headlight Switch (PARKING)    
    Headlight Switch (AUTO)    
    Headlight Switch (HEADLIGHT)    

    Is any data list value OFF, not ON?

    YES 

    Go to step 5.

    NO 

    Go to step 3.

  3. Determine possible failure area (combination light switch, others)

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

    -2. Disconnect the following connector.

    Combination light switch 12P connector

    -3. Check the parameter(s) below with the HDS.

    Signal Current conditions
    Values Unit
    Headlight Switch (OFF)    
    Headlight Switch (PARKING)    
    Headlight Switch (AUTO)    
    Headlight Switch (HEADLIGHT)    

    Are all data lists values OFF?

    YES 

    Replace the combination light switch .

    NO 

    Go to step 4.

  4. Shorted wire check (H/L OFF SW, H/L ON SW, PARKING LT SW lines)

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

    -2. Disconnect the following connector.

    Body control module connector C (28P)

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

    Test condition Vehicle OFF (LOCK) mode
    Combination light switch 12P connector: disconnected
    Body control module connector C (28P): disconnected
    Test point 1 Body control module connector C (28P) No. 10
    Test point 2 Body ground
    Test point 1 Body control module connector C (28P) No. 9
    Test point 2 Body ground
    Test point 1 Body control module connector C (28P) No. 11
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short to ground in the wire.

    NO 

    The H/L OFF SW, H/L ON SW, and PARKING LT SW wires are OK. Replace the body control module .

  5. Determine possible failure area (combination light switch, others)

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

    -2. Disconnect the following connector.

    Combination light switch 12P connector

    -3. Connect terminals A and B with jumper wires.

    Terminal A Combination light switch 12P connector No. 1
    Terminal B Body ground
    Terminal A Combination light switch 12P connector No. 7
    Terminal B Body ground
    Terminal A Combination light switch 12P connector No. 8
    Terminal B Body ground
    GHH400259Courtesy of HONDA, U.S.A., INC.

    -4. Check the parameter(s) below with the HDS.

    Signal Current conditions
    Values Unit
    Headlight Switch (OFF)    
    Headlight Switch (PARKING)    
    Headlight Switch (AUTO)    
    Headlight Switch (HEADLIGHT)    

    Has the data list value changed from OFF to ON?

    YES 

    Replace the combination light switch .

    NO 

    Go to step 6.

  6. Open wire check (H/L OFF SW, H/L ON SW, PARKING LT SW, COMBI SW GND (LT) lines)

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

    -2. Disconnect the following connector.

    Body control module connector C (28P)

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

    Test condition Vehicle OFF (LOCK) mode
    Body control module connector C (28P): disconnected
    Combination light switch 12P connector: disconnected
    Test point 1 Body control module connector C (28P) No. 10
    Test point 2 Combination light switch 12P connector No. 1
    Test point 1 Body control module connector C (28P) No. 9
    Test point 2 Combination light switch 12P connector No. 7
    Test point 1 Body control module connector C (28P) No. 11
    Test point 2 Combination light switch 12P connector No. 8
    Test point 1 Body control module connector C (28P) No. 3
    Test point 2 Combination light switch 12P connector No. 6
    GHH400260Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The H/L OFF SW, H/L ON SW, PARKING LT SW, and COMBI SW GND (LT) wires are OK. Replace the body control module .

    NO 

    Repair an open or high resistance in the wire.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.