B1442

HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1442/42: Air Inlet Damper Control Servo Motor Circuit
B1442/42 - Air Inlet Damper Control Servo Motor Circuit

DESCRIPTION

The air inlet control servo motor sends pulse signals to indicate the damper position to the air conditioning amplifier assembly. The air conditioning amplifier assembly 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 air conditioning amplifier assembly communicates with the servo through a communication/driver IC and wiring assembly called the air conditioning harness assembly.

HINT
Confirm that no mechanical problem is present because this DTC can be stored when either a damper link or the damper is mechanically locked.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Operate the R/F (Recirculation/Fresh) switch.

(e) Enter the following menus: Body Electrical / Air Conditioner / Data List.

(f) Check the value(s) by referring to the table below.

Air Conditioner





OK:

The display is as specified in the Normal Condition column.

Result:





C -- REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Removal

B -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures
A -- Continue to next step.

2. PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Air Conditioner / Active Test.

(e) Check the operation by referring to the table below.

Air Conditioner





OK:

Recirculation damper position changes in accordance with each control range.

NG -- INSPECT AIR INLET CONTROL SERVO MOTOR

OK -- REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Removal

3. INSPECT AIR INLET CONTROL SERVO MOTOR

(a) Replace the air inlet control servo motor Disassembly.

HINT
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.

(b) Check for the DTC.

Result:





B -- END (AIR INLET CONTROL SERVO MOTOR WAS DEFECTIVE)
A -- Continue to next step.

4. INSPECT AIR CONDITIONING HARNESS ASSEMBLY

(a) Replace the air conditioning harness assembly Disassembly.

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

(b) Check for the DTC.

Result:





B -- END (AIR CONDITIONING HARNESS ASSEMBLY WAS DEFECTIVE)

A -- REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Removal