DTC B1223 (10)
DTC B1223 or DTC indicator 10 : A Problem in the Rear Blower Motor Circuit
| DTC Description | DTC |
|---|---|
| B1223 A problem in the rear blower motor circuit |
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. Check for DTCs.
DTC Description DTC B1223 A problem in the rear blower motor circuit Is DTC B1223 or 10 indicated?
YES
Go to step 2.
NO
Intermittent failure. Check for loose wires or poor connections on the rear blower motor circuit.
- Fuse check
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Check the following fuse.
Fuse No. A1-2 (30 A) Location Under-hood fuse/relay box Is the fuse OK?
YES
Go to step 3.
NO
Replace the fuse, and recheck. If fuse blows again, repair a short in the No. A1-2 (30 A) fuse circuit.
- Rear blower motor power circuit check (RR BLOWER MTR+ line)
- 1. Disconnect the following connector.
Rear blower motor 2P connector - 2. Turn the vehicle to the ON mode.
- 3. Measure the voltage between test points 1 and 2.
Test condition Vehicle ON mode Rear blower motor 2P connector: disconnected Test point 1 Rear blower motor 2P connector No. 2 Test point 2 Body ground Is there battery voltage?
YES
Go to step 4.
NO
Go to step 12.
- Blower motor operation check (RR BLOWER MTR- line)
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Reconnect the rear blower motor 2P connector.
- 3. Connect terminals A and B with a jumper wire.
Terminal A Rear blower motor 2P connector No. 1 Terminal B Body ground - 4. Turn the vehicle to the ON mode.
Does the rear blower motor run at high speed?
YES
Go to step 5.
NO
Replace the rear blower motor - Refer to: Blower Motor Removal and Installation, or Rear Blower Motor Removal and Installation .
- Open wire check (SGND line)
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the jumper wire.
- 3. Disconnect the following connector.
Rear blower power transistor 4P connector - 4. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Rear blower power transistor 4P connector: disconnected Test point 1 Rear blower power transistor 4P connector No. 3 Test point 2 Body ground Is there continuity?
YES
The SGND wire is OK. Go to step 6.
NO
Check for an open in the wire between the rear blower power transistor and body ground. If the wire is OK, check for poor ground at G201.
- Open wire check (RR BLOWER MTR- line)
- 1. Connect terminals A and B with a jumper wire.
Terminal A Rear blower power transistor 4P connector No. 3 Terminal B Rear blower power transistor 4P connector No. 4 - 2. Turn the vehicle to the ON mode.
Does the rear blower motor run at high speed?
YES
The RR BLOWER MTR- wire is OK. Go to step 7.
NO
Repair an open in the wire between the rear blower power transistor and the rear blower motor.
- Shorted wire check (R-BLW-V line)
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the jumper wire.
- 3. Disconnect the following connector.
HVAC control unit connector A (32P) - 4. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode HVAC control unit connector A (32P): disconnected Rear blower power transistor 4P connector: disconnected Test point 1 HVAC control unit connector A (32P) No. 29 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 rear blower power transistor.
NO
The R-BLW-V wire is not shorted. Go to step 8.
- Shorted wire check (R-BLW-G line)
- 1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode HVAC control unit connector A (32P): disconnected Rear blower power transistor 4P connector: disconnected Test point 1 HVAC control unit connector A (32P) No. 30 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 rear blower power transistor.
NO
The R-BLW-G wire is not shorted. Go to step 9.
- Open wire check (R-BLW-G line)
- 1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode HVAC control unit connector A (32P): disconnected Rear blower power transistor 4P connector: disconnected Test point 1 HVAC control unit connector A (32P) No. 30 Test point 2 Rear blower power transistor 4P connector No. 1 Is there continuity?
YES
The R-BLW-G wire is OK. Go to step 10.
NO
Repair an open in the wire between the HVAC control unit and the rear blower power transistor.
- Open wire check (R-BLW-V line)
- 1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode HVAC control unit connector A (32P): disconnected Rear blower power transistor 4P connector: disconnected Test point 1 HVAC control unit connector A (32P) No. 29 Test point 2 Rear blower power transistor 4P connector No. 2 Is there continuity?
YES
The R-BLW-V wire is OK. Go to step 11.
NO
Repair an open in the wire between the HVAC control unit and the rear blower power transistor.
- Rear blower power transistor check
- 1. Test the rear blower power transistor.
Is the rear blower power transistor OK?
YES
Replace the HVAC control unit .
NO
Replace the rear blower power transistor - Refer to: Blower Power Transistor Removal and Installation, or Rear Blower Power Transistor Removal and Installation .
NOTE: If the rear blower power transistor is faulty, check the blower motor for damage. If necessary, replace the rear blower motor - Refer to: Blower Motor Removal and Installation, or Rear Blower Motor Removal and Installation . - Rear blower motor relay check
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Remove the rear blower motor relay from the auxiliary under-dash relay holder D, and test it.
Is the relay OK?
YES
Go to step 13.
NO
Replace the rear blower motor relay.
- Open wire check (+B RR BLOWER line)
- 1. Measure the voltage between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Rear blower motor relay: disconnected Test point 1 Rear blower motor relay 4P socket No. 1 Test point 2 Body ground Is there battery voltage?
YES
The +B RR BLOWER line is OK. Go to step 14.
NO
Repair an open in the wire between the No. A1-2 (30 A) fuse in the under-hood fuse/relay box and the rear blower motor relay. If the wire is OK, replace the under-hood fuse/relay box .
- Open wire check (IG2 A/C line)
- 1. Turn the vehicle to the ON mode.
- 2. Measure the voltage between test points 1 and 2.
Test condition Vehicle ON mode Rear blower motor relay: disconnected Test point 1 Rear blower motor relay 4P socket No. 3 Test point 2 Body ground Is there battery voltage?
YES
The IG2 A/C wire is OK. Go to step 15.
NO
Repair an open in the wire between the No. C23 (7.5 A) fuse in the under-dash fuse/relay box and the rear blower motor relay.
- Open wire check (GND line)
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Rear blower motor relay: disconnected Test point 1 Rear blower motor relay 4P socket No. 4 Test point 2 Body ground Is there continuity?
YES
Repair an open in the wire between the rear blower motor relay and the rear blower motor.
NO
Check for an open in the wire between the rear blower motor relay and body ground. If the wire is OK, check for poor ground at G405.