DTC Troubleshooting: B1275, B1276, B1277, B1278
DTC B1275: Headlight OFF Position Circuit Malfunction
DTC B1276: B1276 Head Light Switch Parking (small) Position Circuit Malfunction
DTC B1277: Headlight AUTO Position Circuit Malfunction
DTC B1278: Headlight ON Position Circuit Malfunction
DTC Description
DTC
B1275 Headlight OFF Position Circuit Malfunction
  
B1276 Head light switch parking (small) position circuit malfunction
  
B1277 Headlight AUTO Position Circuit Malfunction
  
B1278 Headlight ON Position Circuit Malfunction
  

NOTE: Refer to the Electrical Wiring Diagrams for the location of the under-dash fuse/relay box connectors.

1.
Problem verification:

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:

Exterior lights system check
?1.
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)
    

Is 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):

Determine possible failure area (combination light switch, others)
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following 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)
    

Has the data list value changed from ON to OFF?

     
YES
     
     
     
     
NO
     
     
     
Go to step 4.
4.
Shorted wire check (H/L OFF SW, H/L ON SW, PARKING LT SW lines):

Shorted wire check (H/L OFF SW, H/L ON SW, PARKING LT SW lines)
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Check for continuity between test points 1 and 2 individually.
Test condition
IG LOCK (0) or OFF mode
Combination light switch 12P connector: disconnected
Under-dash fuse/relay box connector N (20P): disconnected
Test circuit
H/L OFF SW
Test point 1
Under-dash fuse/relay box connector N (20P) No. 18 (PNK)
Test point 2
Body ground

Test circuit
H/L ON SW
Test point 1
Under-dash fuse/relay box connector N (20P) No. 19 (YEL)
Test point 2
Body ground

Test circuit
PARKING LT SW
Test point 1
Under-dash fuse/relay box connector N (20P) No. 20 (GRY)
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. Faulty MICU; replace the under-dash fuse/relay box.?
5.
Determine possible failure area (combination light switch, others):

Determine possible failure area (combination light switch, others)
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Connect terminals A and B with a jumper wire.
Terminal A
Combination light switch 12P connector No. 1 (PNK)
Terminal B
Body ground

Terminal A
Combination light switch 12P connector No. 7 (YEL)
Terminal B
Body ground

Terminal A
Combination light switch 12P connector No. 8 (GRY)
Terminal B
Body ground


?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
     
     
     
     
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):

Open wire check (H/L OFF SW, H/L ON SW, PARKING LT SW, COMBI SW GND (LT) lines)
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Check for continuity between test points 1 and 2 respectively.
Test condition
IG LOCK (0) or OFF mode
Under-dash fuse/relay box connector N (20P): disconnected
Combination light switch 12P connector: disconnected
Test circuit
H/L OFF SW
Test point 1
Under-dash fuse/relay box connector N (20P) No. 18 (PNK)
Test point 2
Combination light switch 12P connector No. 1 (PNK)

Test circuit
H/L ON SW
Test point 1
Under-dash fuse/relay box connector N (20P) No. 19 (YEL)
Test point 2
Combination light switch 12P connector No. 7 (YEL)

Test circuit
PARKING LT SW
Test point 1
Under-dash fuse/relay box connector N (20P) No. 20 (GRY)
Test point 2
Combination light switch 12P connector No. 8 (GRY)

Test circuit
COMBI SW GND (LT)
Test point 1
Under-dash fuse/relay box connector N (20P) No. 1 (BLK)
Test point 2
Combination light switch 12P connector No. 6 (BLK)


Is there continuity?

     
YES
     
     
     
The H/L OFF SW, H/L ON SW, PARKING LT SW, and COMBI SW GND (LT) wires are OK. Faulty MICU; replace the under-dash fuse/relay box.?
     
NO
     
     
     
Repair an open or high resistance in the wire.?