| Last Modified: 08-21-2023 | 6.11:8.1.0 | Doc ID: RM100000001A3O7 |
| Model Year Start: 2019 | Model: Avalon HV | Prod Date Range: [04/2018 - ] |
| Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): B1441,B1446,B1448; Air Mix Damper Control Servo Motor Circuit (Passenger Side); 2019 - 2022 MY Avalon HV [04/2018 - ] | ||
|
DTC |
B1441 |
Air Mix Damper Control Servo Motor Circuit (Passenger Side) |
|
DTC |
B1446 |
Air Mix Damper Control Servo Motor Circuit (Driver Side) |
|
DTC |
B1448 |
FACE Servo Motor Circuit(Passenger Side) |
DESCRIPTION
- B1441: The No. 1 air conditioning radiator damper servo sub-assembly (front passenger side air mix) 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 these signals to move the No. 1 air conditioning radiator damper servo sub-assembly (front passenger side air mix) to the appropriate position. This adjusts the amount of air passing through the heater core after passing the evaporator and controls the temperature of the output air. The air conditioning amplifier assembly communicates with the servo through a communication/driver IC and wiring assembly called the air conditioning harness assembly.
- B1446: The No. 1 air conditioning radiator damper servo sub-assembly (driver side air mix) 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 these signals to move the No. 1 air conditioning radiator damper servo sub-assembly (driver side air mix) to the appropriate position. As a result, the amount of air passing through the heater core after passing through the evaporator is adjusted, and the temperature of the air blowing toward the driver side is controlled. The air conditioning amplifier assembly communicates with the servo through a communication/driver IC and wiring assembly called the air conditioning harness assembly.
- B1448: The No. 1 air conditioning radiator damper servo sub-assembly (front passenger side mode) 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 these signals to move the air outlet damper to the appropriate position, which controls the air outlet switching. The air conditioning amplifier assembly communicates with the servo through a communication/driver IC and wiring assembly called the air conditioning harness assembly.
|
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
Memory |
|---|---|---|---|---|
|
B1441 |
Air Mix Damper Control Servo Motor Circuit (Passenger Side) |
Air mix damper position sensor value does not change even if air conditioning amplifier assembly operates No. 1 air conditioning radiator damper servo sub-assembly (front passenger side air mix) |
|
Memorized (30 sec. or more)* |
|
B1446 |
Air Mix Damper Control Servo Motor Circuit (Driver Side) |
Air mix damper position sensor value does not change even if air conditioning amplifier assembly operates No. 1 air conditioning radiator damper servo sub-assembly (driver side air mix) |
|
Memorized (30 sec. or more)* |
|
B1448 |
FACE Servo Motor Circuit(Passenger Side) |
Air outlet damper position sensor value does not change even if air conditioning amplifier assembly operates No. 1 air conditioning radiator damper servo sub-assembly (front passenger side mode) |
|
Memorized (30 sec. or more)* |
- *: The air conditioning amplifier assembly stores this DTC if the malfunction has occurred for the period of time indicated in the brackets.
DTC Detection Condition Combination Table
|
Vehicle Condition |
|||
|---|---|---|---|
|
Pattern 1 |
Pattern 2 |
||
|
Diagnosis Condition |
No. 1 air conditioning radiator damper servo sub-assembly operating |
○ |
○ |
|
Malfunction |
Damper servo operation request signals are output but the damper position sensor value does not change |
○ |
- |
|
Damper servo operation request signals are output but the damper position sensor value is abnormal |
- |
○ |
|
|
Detection Time |
Continuously for 30 seconds or more |
Continuously for 30 seconds or more |
|
|
Trip Count |
1 trip |
1 trip |
|
HINT:
If the conditions of either of these patterns are detected, a DTC will be stored.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
HINT:
- Confirm that no mechanical problems are present because this DTC can be stored when either a damper link or damper is mechanically locked.
-
When installing a damper servo motor, make sure to install it correctly.
Click here
![2019 MY Avalon HV [04/2018 - 08/2019]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT (for HV Model): REASSEMBLY](/t3Portal/stylegraphics/info.gif)
-
After replacing a damper servo motor, make sure to perform Servo Motor Initialization.
Click here
PROCEDURE
|
1. |
CHECK FOR DTC |
(a) Check for DTCs.
Body Electrical > Air Conditioner > Trouble Codes
|
Result |
Proceed to |
|---|---|
|
Only B1497 is output |
A |
|
B1441, B1442, B1446 and B1448 are output |
B |
|
B1441, B1446 or B1448 is output |
C |
| A |
|
| B |
|
REPLACE NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY
|
|
|
2. |
INSPECT NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY (INSTALLATION CONDITION) |
(a) Check that the No. 1 air conditioning radiator damper servo sub-assembly is installed correctly.
OK:
The No. 1 air conditioning radiator damper servo sub-assembly is installed correctly.
| NG |
|
INSTALL NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY
|
|
|
3. |
INSPECT NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY (MOTOR, LINK, DAMPER) |
(a) Check for a wire harness caught between the links of the motors and dampers.
OK:
No wire harnesses are caught between the links of the motors and dampers.
| NG |
|
REMOVE PINCHED WIRE HARNESS |
|
|
4. |
INSPECT AIR CONDITIONING RADIATOR ASSEMBLY (DAMPER) |
(a) Remove the No. 1 air conditioning radiator damper servo sub-assembly.
Click here
(b) Operate the dampers by hand.
OK:
The dampers are easily operated by hand.
| OK |
|
REPLACE NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY
|
| NG |
|
REPLACE AIR CONDITIONING RADIATOR ASSEMBLY
|
|
|