Kia Sedona (2008 year). Manual - part 251

DTC B2405 AIR MIX MOTOR (REAR)

COMPONENT LOCATION 

Fig. 140: Identifying Temperature Control Actuator Component Location 
Courtesy of KIA MOTORS AMERICA, INC. 

GENERAL DESCRIPTION 

Temperature control actuator located at heater unit, regulates the temperature by the procedure as follows. 
Signal from control unit adjusts position of temp, door by operating temp, motor and then temperature will be 
regulated by the hot/cold air ratio decided by position of temp. door. 

DTC DESCRIPTION 

The A/C controller sets DTC B2405 if the air mix actuator doesn't move to intended position within 40sec (In 
this case, A/C controller try to move temp, door for 2sec. 3 times, every 20 sec. before setting DTC). 

DTC DETECTING CONDITION 

DTC DETECTING CONDITION CHART 

SPECIFICATION 

Item

Detecting Condition

Possible cause

DTC Strategy



Voltage check  



Poor connection of connected part  



Open circuit in harness Short circuit in harness  



Faulty driver Air Mix potentiometer  



Fault A/C Control Unit  

Threshold value



< 0.1V  

Detecting time



0.3 sec  

FAIL SAFE

-

 

2008 Kia Sedona EX 

2008 HVAC Blower & A/C Controls (Automatic) - Sedona

  

Microsoft 

 

Monday, May 24, 2010 3:56:09 PM

Page 126 

© 2006 Mitchell Repair Information Company, LLC. 

Fig. 141: Output Voltage Graph 
Courtesy of KIA MOTORS AMERICA, INC. 

MONITOR SCAN TOOL DATA 

1. Connect scan tool to Data Link Connector (DLC).  

2. Engine "ON"  

3. Monitor the "Rear Air Mix Potentiometer" Parameter on the scan tool while operating temp, switch. 

Fig. 142: Diagnosis Function Screen Display - Air Mix Potentiometer (Rear) 
Courtesy of KIA MOTORS AMERICA, INC. 

4. Are the DTC B2405 present and is parameter of "Rear AIR MIX Potentiometer" fixed? 

There is any fault in Rear AIR MIX Motor. If the parameter of "Driver AIR MIX DOOR" is 30% or less 
when the actuator operates to the hot position, or If the parameter is 60% and more when the actuator 
operates to the cold position. 

YES  

 

2008 Kia Sedona EX 

2008 HVAC Blower & A/C Controls (Automatic) - Sedona

  

Microsoft 

 

Monday, May 24, 2010 3:56:09 PM

Page 127 

© 2006 Mitchell Repair Information Company, LLC. 

Go to TERMINAL AND CONNECTOR INSPECTION procedure.

NO  

Fault is intermittent caused by poor contact in the sensor's and/or A/C controller's connector or was 
repaired and A/C controller memory was not cleared. Thoroughly check connectors for looseness, poor 
connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary 
and then go to "VERIFICATION OF VEHICLE REPAIR" procedure. 

TERMINAL AND CONNECTOR INSPECTION 

1. Many malfunctions in the electrical system are caused by poor harness and terminals. 

Faults can also be caused by interference from other electrical systems, and mechanical or chemical 
damage. 

2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, 

deterioration, or damage.  

3. Has a problem been found? 

YES  

Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR" procedure. 

NO  

Go to "SIGNAL CIRCUIT INSPECTION" procedure. 

SIGNAL CIRCUIT INSPECTION 

1. Check for open in harness. 

1. Ignition "OFF"  

2. Disconnect Rear Air Mix potentiometer.  

3. Measure resistance between terminal "3, 4" of Rear Air Mix Motor and terminal "4, 5" of A/C 

control unit. 

Specification: Approx. 0 ohms 

 

2008 Kia Sedona EX 

2008 HVAC Blower & A/C Controls (Automatic) - Sedona

  

Microsoft 

 

Monday, May 24, 2010 3:56:09 PM

Page 128 

© 2006 Mitchell Repair Information Company, LLC. 

Fig. 143: Checking Resistance Between Terminal "3, 4" Of Rear Air Mix Motor And 
Terminal "4, 5" Of A/C Control Unit 
Courtesy of KIA MOTORS AMERICA, INC. 

4. Is the measured resistance within specifications? 

YES  

Go to step 2. 

NO  

Check for open in signal harness. Repair as necessary and go to "VERIFICATION OF 
VEHICLE REPAIR" procedure. 

2. Check for short to ground in harness. 

1. Ignition "OFF"  

2. Disconnect Rear Air Mix Actuator.  

3. Measure resistance between terminal "3, 4" of Rear Air Mix Motor and chassis ground. 

Specification: Approx. infinity ohms 

Fig. 144: Checking Resistance Between Terminal "3, 4" Of Rear Air Mix Motor And Chassis 

 

2008 Kia Sedona EX 

2008 HVAC Blower & A/C Controls (Automatic) - Sedona

  

Microsoft 

 

Monday, May 24, 2010 3:56:09 PM

Page 129 

© 2006 Mitchell Repair Information Company, LLC.