DTC B1457: Driver Side Air Outlet Damper Control Servo Motor Circuit [12/2013 - 11/2016]: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the Techstream on.
4. Operate the rear passenger side temperature adjustment switch.
5. Enter the following menus: Body Electrical / Air Conditioner / Data List.
6. Check the value(s) by referring to the table below.

   Body Electrical > Air Conditioner > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Air Mix Servo Targ Pls(F&R D)	Rear air mix damper servo sub-assembly target pulse	Min.: 128 Max.: 383	MAX COLD: 9 (pulse) MAX HOT: 54 (pulse)	-
   A/M Servo Actual Pulse(F&R D)	Rear air mix damper servo sub-assembly actual pulse	Min.: 128 Max.: 383	MAX COLD: 9 (pulse) MAX HOT: 54 (pulse)	-

   Body Electrical > Air Conditioner > Data List 

   Tester Display
   Air Mix Servo Targ Pls(F&R D)
   A/M Servo Actual Pulse(F&R D)

   OK

   When the rear passenger side temperature adjustment switch is turned from MAX COLD to MAX HOT, the actual pulse changes following the target pulse.

   Result

   Result	Proceed to
   Target pulse changes but actual pulse does not change	A
   Target pulse and actual pulse do not change	B
   Actual pulse changes following the target pulse (When troubleshooting according to the DTC)	C
   Actual pulse changes following the target pulse (When troubleshooting according to Problem Symptoms Table)	D

Result:  2

B 

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [12/2013 - ] 

Result:  3

C 

See step  5

Result:  4

D 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [12/2013 - 11/2016] 

Result:  1

A 

See step  2

1. Disconnect the L20 No. 2 air conditioning harness assembly connector.
2. Disconnect the F81 air conditioning amplifier assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   F81-27 (R BBU) - L20-4 (R BBU)	Always	Below 1 Ω
   F81-1 (R BUS) - L20-3 (R BUS)	Always	Below 1 Ω
   F81-25 (R BUG) - L20-2 (R BUG)	Always	Below 1 Ω
   F81-27 (R BBU) - Body ground	Always	10 kΩ or higher
   F81-1 (R BUS) - Body ground	Always	10 kΩ or higher
   F81-25 (R BUG) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result:  2

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result:  1

OK 

See step  3

1. Replace the rear air mix damper servo sub-assembly.

   Refer to DISASSEMBLY [12/2013 - ]

   HINT: 

   Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a new or known good one and check that the condition returns to normal.

2. Check for DTCs.

   Refer to DTC CHECK / CLEAR [12/2013 - ]

   Body Electrical > Air Conditioner > Trouble Codes 

   Result

   Result	Proceed to
   DTC B1457 is output	A
   DTC B1457 is not output	B

Result:  2

B 

END (REAR AIR MIX DAMPER SERVO SUB-ASSEMBLY WAS DEFECTIVE) 

Result:  1

A 

See step  4

1. Replace the No. 2 air conditioning harness assembly.

   Refer to DISASSEMBLY [12/2013 - ]

   HINT: 

   Since the No. 2 air conditioning harness assembly cannot be inspected while it is removed from the vehicle, replace the No. 2 air conditioning harness assembly with a new or known good one and check that the condition returns to normal.

2. Check for DTCs.

   Refer to DTC CHECK / CLEAR [12/2013 - ]

   Body Electrical > Air Conditioner > Trouble Codes 

   Result

   Result	Proceed to
   DTC B1457 is output	A
   DTC B1457 is not output	B

Result:  1

A 

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [12/2013 - ] 

Result:  2

B 

END (NO. 2 AIR CONDITIONING HARNESS ASSEMBLY WAS DEFECTIVE) 

1. Check for DTCs.

   Refer to DTC CHECK / CLEAR [12/2013 - ]

   Body Electrical > Air Conditioner > Trouble Codes 

   Result

   Result	Proceed to
   DTC B1457 is output	A
   DTC B1457 is not output	B

Result:  1

A 

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [12/2013 - ] 

Result:  2

B 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2013 - 11/2016]