AIR CONDITIONING SYSTEM, Diagnostic DTC:B1457/57

DTC Code	DTC Name
B1457/57	Driver Side Air Outlet Damper Control Servo Motor Circuit

DESCRIPTION

*1: for LHD
*2: for RHD

The air mix damper servo motor (rear LH*1 or RH*2) sends pulse signals to inform the air conditioning amplifier assembly of the damper position. The air conditioning amplifier assembly activates the motor (normal or reverse) based on the signals to move the air mix damper servo motor (rear LH*1 or RH*2) to any position. As a result, the amount of air that has passed through the evaporator and is passing through the heater core is adjusted, and the temperature of the air blowing toward the rear driver side is controlled.

Tech Tips

Confirm that no mechanical problem is present because this trouble code can be output when either a damper link or damper is mechanically locked.

DTC Code	DTC Detection Condition	Trouble Area
B1457/57	The air mix damper position does not change even if the air conditioning amplifier assembly operates the air mix damper servo motor (rear LH1 or RH2).	Air mix damper servo motor (rear LH)1 Air mix damper servo motor (rear RH)2 Air conditioning harness assembly Air conditioning amplifier assembly

WIRING DIAGRAM

PROCEDURE

READ VALUE USING GTS (AIR MIX SERVO TARG PLS[F&R D], A/M SERVOACTUAL PULSE[F&R D])

*1: for LHD
*2: for RHD

Use the Data List to check if the air mix damper servo motor (rear LH*1 or RH*2) is functioning properly Click here.

Air Conditioner
Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Air Mix Servo Targ Pls(F&R D)	Air mix damper servo motor (rear LH1 or RH2) target pulse / Min.: 128, Max.: 383	for LHD: MAX COLD: 262 (pulse) MAX HOT: 290 (pulse) for RHD: MAX COLD: 250 (pulse) MAX HOT: 222 (pulse)	Displayed between 262 and 290 pulse (for LHD) Displayed between 222 and 250 pulse (for RHD) Air mix damper servo motor (rear LH1 or RH2) system malfunction
A/M Servo Actual Pulse(F&R D)	Air mix damper servo motor (rear LH1 or RH2) actual pulse / Min.: 128, Max.: 383	for LHD: MAX COLD: 262 (pulse) MAX HOT: 290 (pulse) for RHD: MAX COLD: 250 (pulse) MAX HOT: 222 (pulse)	Displayed between 262 and 290 pulse (for LHD) Displayed between 222 and 250 pulse (for RHD) Air mix damper servo motor (rear LH1 or RH2) system malfunction

OK
When the rear temperature adjust switch for driver side 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

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

CHECK FOR DTC Click here

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

CHECK AIR MIX DAMPER SERVO MOTOR (REAR [DRIVER SIDE])
1. for LHD:
  1. Replace the air mix damper servo motor (rear LH) Click here.
2. for RHD:
  1. Replace the air mix damper servo motor (rear RH) Click here.
  Tech Tips
  
  Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a normal one.
3. Clear the DTCs Click here.
4. Check for DTCs Click here.
  
  OK
  
  DTC B1457/57 is not output.
OK
END (AIR MIX DAMPER SERVO MOTOR [REAR DRIVER SIDE] WAS DEFECTIVE)

NG
CHECK AIR CONDITIONING HARNESS ASSEMBLY
1. Replace the air conditioning harness assembly with a new or known good one Click here.
2. Clear the DTCs Click here.
3. Check for DTCs Click here.
  
  OK
  
  DTC B1457/57 is not output.
OK
END (AIR CONDITIONING HARNESS ASSEMBLY WAS DEFECTIVE)

NG
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here
CHECK FOR DTC

OK
USE SIMULATION METHOD TO CHECK Click here

NG
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here