DESCRIPTION
The air inlet control servo motor sends pulse signals to indicate the damper position to the A/C amplifier. The A/C amplifier activates the motor (normal or reverse) based on these signals to move the air inlet mode selection air inlet control damper to any position, which controls the intake air settings (FRESH, FRESH/RECIRCULATION, and RECIRCULATION).
The A/C amplifier communicates with the servo through a communication/driver IC and wiring assembly called the air conditioning harness.
Tech Tips
Confirm that no mechanical problem is present because this DTC can be output when either a damper link or the damper is mechanically locked.
DTC No. | DTC Detection Condition | Trouble Area |
---|---|---|
B1442/42 | Air inlet damper position sensor value does not change even if A/C amplifier operates air inlet control servo motor |
|
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
READ VALUE USING INTELLIGENT TESTER
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG).
Turn the intelligent tester on.
Operate the R/F (Recirculation/Fresh) switch.
Enter the following menus: Body / Air Conditioner / Data List.
Check the value(s) by referring to the table below.
Tester Display | Measurement Item/Range | Normal Condition | Diagnostic Note |
---|---|---|---|
Air Inlet Damper Targ Pulse | Air inlet servo motor target pulse / Min.: 0, Max.: 255 | RECIRCULATION: 19 (pulse) FRESH: 40 (pulse) |
- |
Air Inlet Damper Actual Pulse | Air inlet servo motor actual pulse / Min.: 0, Max.: 255 | RECIRCULATION: 19 (pulse) FRESH: 40 (pulse) |
- |
OK |
---|
The display is as specified in the Normal Condition column. |
Result | ||||||||
---|---|---|---|---|---|---|---|---|
|
B |
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
C |
REPLACE A/C AMPLIFIER Click here |
A |
PERFORM ACTIVE TEST USING INTELLIGENT TESTER
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG).
Turn the intelligent tester on.
Enter the following menus: Body / Air Conditioner / Active Test.
Check the operation by referring to the table below.
Tester Display | Test Part | Control Range | Diagnostic Note |
---|---|---|---|
Air Inlet Damper Targ Pulse | Air inlet damper target pulse | Min.: 0, Max.: 255 | - |
OK |
---|
Recirculation damper position changes in accordance with each control range. |
NG |
INSPECT AIR INLET CONTROL SERVO MOTOR Click here |
OK |
REPLACE A/C AMPLIFIER Click here
INSPECT AIR INLET CONTROL SERVO MOTOR
Replace the air inlet control servo motor Click here.
Tech Tips
Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a new or a known good one and check that the condition returns to normal.
Check for the DTC.
Result | ||||||
---|---|---|---|---|---|---|
|
B |
REPLACE AIR INLET CONTROL SERVO MOTOR Click here |
A |
INSPECT AIR CONDITIONING HARNESS
Replace the air conditioning harness Click here.
Tech Tips
Since the air conditioning harness cannot be inspected while it is removed from the vehicle, replace the air conditioning harness with a new or a known good one and check that the condition returns to normal.
Check for the DTC.
Result | ||||||
---|---|---|---|---|---|---|
|
B |
REPLACE AIR CONDITIONING HARNESS Click here |
A |
REPLACE A/C AMPLIFIER Click here