DTC B1275; DTC B1276; DTC B1277; DTC B1278; Headlight Position Circuit Malfunction

NOTE:  If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A - Refer to: Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC ChecksBody Electrical Troubleshooting - B-CAN System Diagnosis Test Mode 1 and Test Mode 2 (without the HDS)Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode B - Control Unit Not CommunicatingBody Electrical Troubleshooting - B-CAN System Diagnosis Test Mode C - No DTCs and Output Won't Shut OFFBody Electrical Troubleshooting - B-CAN System Diagnosis Test Mode D - No DTCs and Output Won't Turn ON .

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

• 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 (SMALL) 

  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.

  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):

  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)

  Has the data list value changed from ON to OFF?

  YES 

  Replace the combination light switch .

  NO 

  Go to step 4.

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

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

  2. Disconnect the following connector(s).

  Under-dash fuse/relay box connector T (20P) Automatic lighting/rain sensor 5P connector*1 Automatic lighting control unit/sensor 7P connector*2 *1: With automatic lighting and automatic wiper *2: With automatic lighting without automatic wiper

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

  Test condition	Vehicle OFF (LOCK) mode Combination light switch 12P connector: disconnected Under-dash fuse/relay box connector T (20P): disconnected
  Test point 1	Under-dash fuse/relay box connector T (20P) No. 1

  Test point 2

  Body ground

  Test point 1	Under-dash fuse/relay box connector T (20P) No. 2
  Test point 2	Body ground

  Test point 1	Under-dash fuse/relay box connector T (20P) No. 3
  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 SMALL LT SW wires are OK. Faulty MICU; replace the under-dash fuse/relay box .

• 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 a jumper wire.

  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

  Courtesy 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, SMALL LT SW, COMBI SW GND (LT) lines):

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

  2. Disconnect the following connector.

  Under-dash fuse/relay box connector T (20P)

  3. Check for continuity test points 1 and 2.

  Test condition

  Vehicle OFF (LOCK) mode Under-dash fuse/relay box connector T (20P): disconnected Combination light switch 12P connector: disconnected

  Test point 1	Under-dash fuse/relay box connector T (20P) No. 1
  Test point 2	Combination light switch 12P connector No. 1

  Test point 1	Under-dash fuse/relay box connector T (20P) No. 2
  Test point 2	Combination light switch 12P connector No. 7

  Test point 1	Under-dash fuse/relay box connector T (20P) No. 3
  Test point 2	Combination light switch 12P connector No. 8

  Test point 1	Under-dash fuse/relay box connector T (20P) No. 5
  Test point 2	Combination light switch 12P connector No. 6

  Courtesy of HONDA, U.S.A., INC.

  Is there continuity?

  YES 

  The H/L OFF SW, H/L ON SW, SMALL 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.