DTC B1279
DTC B1279 : Dimmer Switch Circuit Malfunction
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 B - Control Unit Not Communicating or Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC Checks or Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode 1 and Test Mode 2 (without the HDS) .
| DTC Description | DTC |
|---|---|
| B1279 Dimmer switch Circuit Malfunction |
DTC (Body Control Module)
- Exterior lights system check 1
-1. With the headlight dimmer switch in the neutral position, check the parameter(s) below with the HDS.
Signal Current conditions Values Unit Headlight Switch (HIGH BEAM) Headlight Switch (PASSING) Is either information indicator ON?
YES
Go to step 4.
NO
Go to step 2.
- Exterior lights system check 2
-1. With the headlight dimmer switch in the high beam position, check the parameter(s) below with the HDS.
Signal Current conditions Values Unit Headlight Switch (HIGH BEAM) Headlight Switch (PASSING) Are both information indicators ON?
YES
Go to step 3.
NO
Intermittent failure, the system is OK at this time.
- Shorted wire check (H/L HI SW to PASSING SW line)
-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 Body control module connector A (66P) No. 25 Terminal B Body ground -4. Check the parameter(s) below with the HDS.
Signal Current conditions Values Unit Headlight Switch (HIGH BEAM) Headlight Switch (PASSING) Are both information indicators ON?
YES
Repair a short between the wires.
NO
The H/L HI SW and PASSING SW wires are OK. Replace the combination light switch .
- 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 (HIGH BEAM) Headlight Switch (PASSING) Is either information indicator ON?
YES
Go to step 5.
NO
- Shorted wire check (PASSING SW, H/L HI SW lines)
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Disconnect the following connector.
Body control module connector A (66P) -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 A (66P): disconnected Test point 1 Body control module connector A (66P) No. 6 Test point 2 Body ground Test point 1 Body control module connector A (66P) No. 25 Test point 2 Body ground Are there continuity?
YES
Repair a short to ground in the wire.
NO
The PASSING SW and H/L HI SW wires are OK. Replace the body control module .