DTC B1234 (3)
DTC B1234 or DTC indicator 3 : A Short in the Air Mix Control Motor Circuit (Front)
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 (front) |
DTC (AC)
- Problem verification
- 1. Clear the DTC 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 HVAC control unit.
- 4. Wait for at least 8 seconds.
- 5. Check for DTCs.
DTC Description DTC B1234 A short in the air mix control motor circuit (front) Is DTC B1234 or 3 indicated?
YES
Go to step 2.
NO
Intermittent failure. Check for loose wires or poor connections on the front air mix control motor circuit.
- Determine possible failure area (SENSOR 5V line, others)
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the following connector.
Front air mix control motor 7P connector - 3. Turn the vehicle to the ON mode.
- 4. Measure the voltage between test points 1 and 2.
Test condition Vehicle ON mode Front air mix control motor 7P connector: disconnected Test point 1 Front air mix control motor 7P connector No. 1 Test point 2 Body ground Is there about 5 V?
YES
The SENSOR 5V wire is OK. Go to step 3.
NO
Go to step 6.
- Front air mix control motor check (AMDP AS line)
- 1. Measure the voltage between test points 1 and 2.
Test condition Vehicle ON mode Front air mix control motor 7P connector: disconnected Test point 1 Front air mix control motor 7P connector No. 2 Test point 2 Body ground Is there about 5 V?
YES
The AMDP AS wire is OK. Replace the front air mix control motor .
NO
Go to step 4.
- Shorted wire check (AMDP AS line)
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the following connector.
HVAC control unit connector C (12P) - 3. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode HVAC control unit connector C (12P): disconnected Front air mix control motor 7P connector: disconnected Test point 1 HVAC control unit connector C (12P) No. 2 Test point 2 Body ground Is there continuity?
YES
Repair a short to body ground in the wire between the HVAC control unit and the front air mix control motor.
NO
The AMDP AS wire is not shorted. Go to step 5.
- Shorted wire check (AMDP AS line to SENSOR(COM) line)
- 1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode HVAC control unit connector C (12P): disconnected Front air mix control motor 7P connector: disconnected Test point 1 Front air mix control motor 7P connector No. 2 Test point 2 Front air mix control motor 7P connector No. 3 Is there continuity?
YES
Repair a short in the wires between the HVAC control unit and the front air mix control motor.
NO
The AMDP AS wire to SENSOR(COM) wire are OK. Replace the HVAC control unit .
- Open wire check (SENSOR 5V line)
- 1. Measure the voltage between test points 1 and 2.
Test condition Vehicle ON mode Front air mix control motor 7P connector: disconnected Test point 1 HVAC control unit connector A (32P) No. 5 Test point 2 Body ground Is there about 5 V?
YES
Repair an open in the wire between the HVAC control unit and the front air mix control motor.
NO
The SENSOR 5V wire is not open. Go to step 7.
- Shorted wire check (SENSOR 5V line)
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the following connector.
HVAC control unit connector A (32P) - 3. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode HVAC control unit connector A (32P): disconnected Front air mix control motor 7P connector: disconnected Test point 1 HVAC control unit connector A (32P) No. 5 Test point 2 Body ground Is there continuity?
YES
Repair a short to body ground in the wire between the HVAC control unit and the front air mix control motor.
NO
The SENSOR 5V wire is OK. Replace the HVAC control unit .