| Last Modified: 08-21-2023 | 6.11:8.1.0 | Doc ID: RM100000001A3OA |
| Model Year Start: 2019 | Model: Avalon HV | Prod Date Range: [04/2018 - ] |
| Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): B1449; Air Outlet Damper Control Servo Motor Circuit (Rear); 2019 - 2022 MY Avalon HV [04/2018 - ] | ||
|
DTC |
B1449 |
Air Outlet Damper Control Servo Motor Circuit (Rear) |
DESCRIPTION
The No. 2 air conditioning radiator damper servo sub-assembly 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 rear 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 |
|---|---|---|---|---|
|
B1449 |
Air Outlet Damper Control Servo Motor Circuit (Rear) |
Air outlet damper position sensor value does not change even if air conditioning amplifier assembly operates No. 2 air conditioning radiator damper servo sub-assembly |
|
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. 2 air conditioning radiator damper servo sub-assembly operating |
○ |
○ |
|
Malfunction |
Air outlet damper servo operation request signals are output but the front passenger side air mix damper position sensor value does not change |
○ |
- |
|
Air outlet damper servo operation request signals are output but the front passenger side air mix 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 |
|---|---|
|
B1497 is not output |
A |
|
B1497 is output |
B |
| B |
|
|
|
2. |
INSPECT NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY (INSTALLATION CONDITION) |
(a) Check that the No. 2 air conditioning radiator damper servo sub-assembly is installed correctly.
Click here
OK:
The No. 2 air conditioning radiator damper servo sub-assembly is installed correctly.
| NG |
|
INSTALL NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY CORRECTLY
|
|
|
3. |
INSPECT NO. 2 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 NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY (DAMPER) |
(a) Remove the No. 2 air conditioning radiator damper servo sub-assembly.
Click here
(b) Operate the dampers by hand.
OK:
The dampers are easily operated by hand.
| NG |
|
REPLACE AIR CONDITIONING RADIATOR ASSEMBLY
|
|
|
5. |
PERFORM ACTIVE TEST USING TECHSTREAM |
(a) Remove the No. 3 air conditioning radiator damper servo sub-assembly.
Click here
(b) Connect the No. 3 air conditioning radiator damper servo sub-assembly connector to the No. 2 air conditioning radiator damper servo sub-assembly.
(c) Connect the Techstream to the DLC3.
(d) Turn the power switch on (IG).
(e) Turn the Techstream on.
(f) Enter the following menus: Body Electrical / Air Conditioner / Active Test.
(g) Perform the Active Test according to the display on the Techstream.
Body Electrical > Air Conditioner > Active Test
|
Tester Display |
Measurement Item |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
Air Outlet Servo Pulse (D) |
No. 3 air conditioning radiator damper servo sub-assembly pulse* |
Min.: 128 Max.: 383 |
Operates between 164 and 278 pulses |
- *: Though this Active Test is for the No. 3 air conditioning radiator damper servo sub-assembly, in this case it is used to check the operation of the No. 2 air conditioning radiator damper servo sub-assembly.
Body Electrical > Air Conditioner > Active Test
|
Tester Display |
|---|
|
Air Outlet Servo Pulse (D) |
OK:
The No. 2 air conditioning radiator damper servo sub-assembly operates.
| OK |
|
REPLACE AIR CONDITIONING HARNESS ASSEMBLY
|
| NG |
|
REPLACE NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY
|
|
|