DTC Troubleshooting: B1234 (B-A2), B1234 (41)
DTC B1234 or DTC screen B-A2 or DTC indicator 41: A short in the air mix control motor circuit (driver's)
NOTE: If other short circuit DTCs are indicated at the same time, there may be an open or short to body ground in the power (5 V) circuit.

DTC Description
DTC
B1234 A short in the air mix control motor circuit (driver's)
  

1.
Problem verification:

Problem verification
?1.
Clear the DTCs with the HDS.


?2.
Turn the vehicle to the OFF (LOCK) mode and 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
B1234 A short in the air mix control motor circuit (driver's)
  

Is DTC B1234 or Error on the DTC screen B-A2 (climate control panel without display) or 41 (climate control panel with display) indicated?

     
YES
     
     
     
Go to step 2.
     
NO
     
     
     
Intermittent failure. Check for loose wires or poor connections on the air mix control motor circuit.?
     
NO
     
     
     
Intermittent failure. Check for loose wires or poor connections on the driver's air mix control motor circuit.?
2.
Determine possible failure area (S5V line, others):

Determine possible failure area (S5V line, others)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
Without dual zone control: Air mix control motor 5P connector
With dual zone control: Driver's air mix control motor 5P connector

?3.
Turn the vehicle to the ON mode.

?4.
Measure the voltage between test points 1 and 2.
Without dual zone control
Test condition
Vehicle ON mode
Air mix control motor 5P connector: disconnected
Test point 1
Air mix control motor 5P connector (female terminals) No. 3:
Test point 2
Body ground

With dual zone control
Test condition
Vehicle ON mode
Driver's air mix control motor 5P connector: disconnected
Test point 1
Driver's air mix control motor 5P connector (female terminals) No. 1:
Test point 2
Body ground


Is there about 5 V?

     
YES
     
     
     
The S5V wire is OK. Go to step 3.
     
NO
     
     
     
Go to step 4.
3.
Determine possible failure area (air mix control motor (without dual zone control) or driver's air mix control motor (with dual zone control) check, others):

Determine possible failure area (air mix control motor (without dual zone control) or driver's air mix control motor (with dual zone control) check, others)
?1.
Measure the voltage between test points 1 and 2.
Without dual zone control
Test condition
Vehicle ON mode
Air mix control motor 5P connector: disconnected
Test point 1
Air mix control motor 5P connector (female terminals) No. 2:
Test point 2
Body ground

With dual zone control
Test condition
Vehicle ON mode
Driver's air mix control motor 5P connector: disconnected
Test point 1
Driver's air mix control motor 5P connector (female terminals) No. 2:
Test point 2
Body ground


Is there about 5 V?

     
YES
     
     
     
     
NO
     
     
     
Go to step 6.
4.
Open wire check (S5V line):

Open wire check (S5V line)
?1.
Measure the voltage between test points 1 and 2.
Without dual zone control
Test condition
Vehicle ON mode
Air mix control motor 5P connector: disconnected
Test point 1
Climate control unit connector B (24P) No. 1
Test point 2
Body ground

With dual zone control
Test condition
Vehicle ON mode
Driver's air mix control motor 5P connector: disconnected
Test point 1
Climate control unit connector B (24P) No. 1
Test point 2
Body ground

Is there about 5 V?

     
YES
     
     
     
Repair an open in the S5V wire.?
     
NO
     
     
     
The S5V wire is not open. Go to step 5.
5.
Shorted wire check (S5V line):

Shorted wire check (S5V line)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
Climate control unit connector B (24P)

?3.
Check for continuity between test points 1 and 2.
Without dual zone control
Test condition
Vehicle OFF (LOCK) mode
Climate control unit connector B (24P): disconnected
Air mix control motor 5P connector: disconnected
Test point 1
Climate control unit connector B (24P) No. 1
Test point 2
Body ground

With dual zone control
Test condition
Vehicle OFF (LOCK) mode
Climate control unit connector B (24P): disconnected
Driver's air mix control motor 5P connector: disconnected
Test point 1
Climate control unit connector B (24P) No. 1
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
Repair a short to ground in the S5V wire.?
     
NO
     
     
     
6.
Shorted wire check (AMD-P-DR line):

Shorted wire check (AMD-P-DR line)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
Climate control unit connector B (24P)

?3.
Check for continuity between test points 1 and 2.
Without dual zone control
Test condition
Vehicle OFF (LOCK) mode
Climate control unit connector B (24P): disconnected
Air mix control motor 5P connector: disconnected
Test point 1
Climate control unit connector B (24P) No. 2
Test point 2
Body ground

With dual zone control
Test condition
Vehicle OFF (LOCK) mode
Climate control unit connector B (24P): disconnected
Driver's air mix control motor 5P connector: disconnected
Test point 1
Climate control unit connector B (24P) No. 2
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
Repair a short to ground in the AMD-P-DR wire.?
     
NO