B1442

AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1442: Air Inlet Damper Control Servo Motor Circuit

DTC B1442 - Air Inlet Damper Control Servo Motor Circuit

DESCRIPTION

The air inlet control servo motor is controlled by the air conditioning amplifier and moves the air inlet control servo motor to the desired position.
The air inlet control servo motor switches between "RECIRCULATION" and "FRESH" by rotating the motor (normal, reverse) with electrical power from the air conditioning amplifier. This controls intake air and switches "RECIRCULATION", "FRESH" and "HALF-RECIRCULATION".






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM
(a) Connect Techstream to DLC3.
(b) Turn the power switch ON and turn Techstream ON.
(c) Select the item below in the Data List, and read the display on Techstream.

Air conditioning amplifier





OK:
When the target position is at the "RECIRCULATION" (-1.0%), the actual opening angle is 19.0% or less.

Result





C -- REPLACE AIR CONDITIONING AMPLIFIER
B -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
A -- Continue to next step.

2. READ VALUE USING TECHSTREAM
(a) Connect Techstream to DLC3.
(b) Turn the power switch ON (IG) and turn Techstream ON.
(c) Select the item below in the Data List, and read the display on Techstream.

Air conditioning amplifier





OK:
When the target position is at the "FRESH" (110.0%), the actual opening angle is 81.0% or more.

Result





C -- REPLACE AIR CONDITIONING AMPLIFIER
B -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
A -- Continue to next step.

3. INSPECT AIR INLET CONTROL SERVO MOTOR




(a) Remove the damper air inlet servo motor.
(b) Connect the battery's positive (+) lead to terminal 5 and negative (-) lead to terminal 4 then check that the lever turns to "FRESH" position smoothly.
(c) Measure the resistance of the servo motor.
Standard resistance:





(d) Connect the battery's positive (+) lead to terminal 4 and negative (-) lead to terminal 5 then check that the lever turns to "RECIRCULATION" position smoothly.
(e) Measure the resistance of the servo motor.
Standard resistance:






NG -- REPLACE AIR INLET CONTROL SERVO MOTOR
OK -- Continue to next step.

4. CHECK WIRE HARNESS (AIR INLET CONTROL SERVO MOTOR - AIR CONDITIONING AMPLIFIER)




(a) Disconnect the A14 servo connector.
(b) Disconnect the A8 amplifier connector.
(c) Measure the resistance of the wire harness side connectors.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- REPLACE AIR CONDITIONING AMPLIFIER