| Last Modified: 05-13-2024 | 6.11:8.1.0 | Doc ID: RM100000001H97A |
| Model Year Start: 2020 | Model: Corolla | Prod Date Range: [01/2019 - 09/2022] |
| Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): B1442; Air Inlet Damper Control Servo Motor; 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022] | ||
|
DTC |
B1442 |
Air Inlet Damper Control Servo Motor |
DESCRIPTION
The No. 1 blower 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 inlet damper to the appropriate position to change the air inlet mode (fresh, recirculation/fresh, 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.
|
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
Memory |
|---|---|---|---|---|
|
B1442 |
Air Inlet Damper Control Servo Motor |
Air inlet damper position sensor value does not change even if air conditioning amplifier assembly operates No. 1 blower 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. 3 air conditioning radiator damper servo sub-assembly operating |
○ |
○ |
|
Malfunction |
Air inlet damper servo operation request signals are output but the air inlet damper position sensor value does not change |
○ |
- |
|
Air inlet damper servo operation request signals are output but the air inlet 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
NOTICE:
-
This DTC is also output for the damper link, damper lock, etc. Before performing inspection, perform servomotor initialization and check that there are no mechanical malfunctions.
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![2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): INITIALIZATION](/t3Portal/stylegraphics/info.gif)
-
This DTC is also output when servomotor initialization has failed. When servomotor initialization has failed, repair any malfunctions and perform servomotor initialization again.
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PROCEDURE
|
1. |
CHECK FOR DTC |
(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 / Trouble Codes.
(e) Check for DTCs.
Body Electrical > Air Conditioner > Trouble Codes
|
Result |
Proceed to |
|---|---|
|
B1497 is output |
A |
|
B1441, B1442 and B1443 are output |
B |
|
Only B1442 is output |
C |
| A |
|
| B |
|
REPLACE NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY
|
|
|
2. |
INSPECT NO. 1 BLOWER DAMPER SERVO SUB-ASSEMBLY (INSTALLATION CONDITION) |
(a) Check that the No. 1 blower damper servo sub-assembly is installed correctly.
OK:
The No. 1 blower damper servo sub-assembly is installed correctly.
| NG |
|
|
|
3. |
INSPECT NO. 1 BLOWER 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. 1 BLOWER DAMPER SERVO SUB-ASSEMBLY (DAMPER) |
(a) Remove the No. 1 blower damper servo sub-assembly.
Click here
(b) Operate the air inlet dampers by hand.
OK:
The air inlet dampers are easily operated by hand.
| NG |
|
REPLACE BLOWER ASSEMBLY
|
|
|
5. |
INSPECT AIR CONDITIONING HARNESS ASSEMBLY |
(a) Disconnect the No. 1 air conditioning radiator damper servo sub-assembly connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
A-6 (STE2) - B-3 (sigB) |
Always |
Below 1 Ω |
|
A-5 (STE1) - B-2 (sigA) |
Always |
Below 1 Ω |
|
A-8 (M-) - B-5 (M-) |
Always |
Below 1 Ω |
|
A-7 (M+) - B-4 (M+) |
Always |
Below 1 Ω |
|
A-4 (GND) - B-1 (GND) |
Always |
Below 1 Ω |
|
A-6 (STE2) or B-3 (sigB) - Other terminals and Body ground |
Always |
10 kΩ or higher |
|
A-5 (STE1) or B-2 (sigA) - Other terminals and Body ground |
Always |
10 kΩ or higher |
|
A-8 (M-) or B-5 (M-) - Other terminals and Body ground |
Always |
10 kΩ or higher |
|
A-7 (M+) or B-4 (M+) - Other terminals and Body ground |
Always |
10 kΩ or higher |
| NG |
|
REPLACE AIR CONDITIONING HARNESS ASSEMBLY
|
|
|
6. |
PERFORM ACTIVE TEST USING TECHSTREAM |
(a) Connect the No. 1 air conditioning radiator damper servo sub-assembly connector.
(b) Remove the No. 2 air conditioning radiator damper servo sub-assembly.
Click here
(c) Connect the No. 3 air conditioning radiator damper servo sub-assembly connector to the No. 2 air conditioning radiator damper servo sub-assembly.
(d) Connect the Techstream to the DLC3.
(e) Turn the power switch on (IG).
(f) Turn the Techstream on.
(g) Enter the following menus: Body Electrical / Air Conditioner / Active Test.
(h) 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 NO. 3 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY |
| NG |
|
REPLACE NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY
|
|
|