DTC B123F (E and AUTO)
DTC B123F or DTC indicator E and AUTO : Automatic lighting control unit/sunlight sensor error
| DTC Description | DTC |
|---|---|
| B123F Automatic lighting control unit/sunlight sensor error |
DTCs (AC)
- Problem verification
-1. Clear the DTCs with the HDS.
-2. Turn the vehicle to the OFF (LOCK) mode, 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 B123F Automatic lighting control unit/sunlight sensor error Is DTC B123F or E and AUTO indicated?
YES
Go to step 2.
NO
Intermittent failure, the system is OK at this time.
- Equipment check 1
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Confirm the vehicle have an automatic lighting system.
Does the combination light switch have an AUTO position?
YES
Go to step 3.
NO
Go to step 4.
- Equipment check 2
-1. Confirm the vehicle have an automatic wiper system.
Does the wiper/washer switch have an AUTO position?
YES
Go to step 4.
NO
Go to step 9.
- Open wire check (TSUN line)
-1. Disconnect the following connectors.
Climate control unit connector A (32P) Sunlight sensor 2P connector -2. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Climate control unit connector A (32P): disconnected Sunlight sensor 2P connector: disconnected Test point 1 Climate control unit connector C (12P) No. 10 Test point 2 Sunlight sensor 2P connector (female terminals) No. 2: Is there continuity?
YES
The TSUN wire is not open. Go to step 5.
NO
Repair an open in the TSUN wire.
- Open wire check (SENSOR COM line)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Climate control unit connector A (32P): disconnected Sunlight sensor 2P connector: disconnected Test point 1 Climate control unit connector A (32P) No. 18 Test point 2 Sunlight sensor 2P connector (female terminals) No. 1: Is there continuity?
YES
The SENSOR COM wire is OK. Go to step 6.
NO
Repair an open in the SENSOR COM wire.
- Shorted wire check (TSUN line)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Climate control unit connector A (32P): disconnected Sunlight sensor 2P connector: disconnected Test point 1 Climate control unit connector C (12P) No. 10 Test point 2 Body ground Is there continuity?
YES
Repair a short to ground in the TSUN wire.
NO
The TSUN wire is not shorted. Go to step 7.
- Shorted wire check (TSUN line to SENSOR COM 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 unit connector C (12P): disconnected Sunlight sensor 2P connector: disconnected Test point 1 Climate control unit connector A (32P) No. 18 Test point 2 Climate control unit connector C (12P) No. 10 Is there continuity?
YES
Repair a short in the TSUN wire to SENSOR COM wire.
NO
The TSUN wire and SENSOR COM wire are OK. Go to step 8.
- Sunlight sensor check
-1. Reconnect the following connectors.
Climate control unit connector A (32P) Climate control unit connector C (12P) Sunlight sensor 2P connector -2. Test the sunlight sensor .
Is the sunlight sensor OK?
YES
Replace the climate control unit .
NO
- Fuse check:NOTE: Check for DTCs. If a DTC U1280 indicated, troubleshoot the DTC first.
-1. Check the following fuse.
Fuse No. A15 (10 A) *1 Fuse No. A26 (10 A) *2 Location Under-hood fuse/relay box *1: With AC power outlet
*2: Without AC power outlet
Is the fuse OK?
YES
Go to step 10.
NO
Replace the fuse, and recheck. If the fuse blows again, repair a short in the No. A15 (10 A) *1 or No. A26 (10 A) *2 fuse circuit.
- Determine possible failure area (B-CAN lines, others)
-1. Disconnect the following connector.
Sunlight sensor 5P connector -2. Measure the voltage between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Sunlight sensor 5P connector: disconnected Test point 1 Sunlight sensor 5P connector No. 3 Test point 2 Sunlight sensor 5P connector No. 4 Is there battery voltage?
YES
Go to step 11.
NO
Go to step 14.
- Open wire check (B-CAN H line)
-1. Disconnect the following connector.
Climate control unit connector A (32P) -2. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Sunlight sensor 5P connector: disconnected Climate control unit connector A (32P): disconnected Test point 1 Sunlight sensor 5P connector No. 1 Test point 2 Climate control unit connector A (32P) No. 23 Is there continuity?
YES
The B-CAN H wire is OK. Go to step 12.
NO
Repair an open in the B-CAN H wire.
- Open wire check (B-CAN L line)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Sunlight sensor 5P connector: disconnected Climate control unit connector A (32P): disconnected Test point 1 Sunlight sensor 5P connector No. 2 Test point 2 Climate control unit connector A (32P) No. 24 Is there continuity?
YES
The B-CAN L wire is OK. Go to step 13.
NO
Repair an open in the B-CAN L wire.
- DTC check
-1. Reconnect the following connectors.
Sunlight sensor 5P connector Climate control unit connector A (32P) -2. Clear the DTC with the HDS.
-3. Turn the vehicle to the OFF (LOCK) mode, then the ON mode.
-4. Wait for at least 8 seconds.
-5. Do the Self-Diagnostic Function with the climate control unit .
-6. Check for DTCs.
DTC Description DTC B123F Automatic lighting control unit-sensor (sunlight sensor) internal error U128D Lost communication with gauge control module Is DTC B123F or E and AUTO and DTC U128D indicated?
YES
Replace the climate control unit .
NO
- Open wire check (+B BACKUP line)
-1. Measure the voltage between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Sunlight sensor 5P connector: disconnected Test point 1 Sunlight sensor 5P connector No. 4 Test point 2 Body ground Is there battery voltage?
YES
Check for an open in the GND wire. If the wire is OK, check for poor ground at G401.
NO
Repair an open in the +B BACKUP wire.