- Air conditioning amplifier assembly malfunction
- Blower motor with fan sub-assembly malfunction
- Harness or connector
| Last Modified: 05-13-2024 | 6.11:8.1.0 | Doc ID: RM1000000026Z4D |
| Model Year Start: 2023 | Model: Corolla | Prod Date Range: [09/2022 - ] |
| Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): Blower Motor Circuit; 2023 - 2025 MY Corolla Corolla HV [09/2022 - ] | ||
|
Blower Motor Circuit |
DESCRIPTION
The blower motor with fan sub-assembly is operated by signals from the air conditioning amplifier assembly.
If the airflow volume is low or the blower speed cannot be changed, the following factors may be the cause.
|
Symptom |
Factor |
|---|---|
|
Airflow volume cannot be changed |
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
|
1. |
PERFORM ACTIVE TEST USING GTS |
(a) Perform the Active Test according to the display on the GTS.
Body Electrical > Air Conditioner > Active Test
|
Tester Display |
Measurement Item |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
Blower Level |
This test activates the Blower Motor to adjust the air volume High/Low. (Blower motor with fan sub-assembly) |
0: Air Volume Low 31: Air Volume High |
Operate with ignition switch ON. |
Body Electrical > Air Conditioner > Active Test
|
Tester Display |
|---|
|
Blower Level |
|
Result |
Proceed to |
|---|---|
|
Blower motor with fan sub-assembly does not operate |
A |
|
Blower motor with fan sub-assembly operates but does not change speed |
B |
| B |
|
|
|
2. |
CHECK HARNESS AND CONNECTOR (BLOWER MOTOR WITH FAN SUB-ASSEMBLY - AUXILIARY BATTERY AND BODY GROUND) |
|
(a) Disconnect the A11 blower motor with fan sub-assembly connector. |
|
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
A11-1 (GND) - Body ground |
Always |
Below 1 Ω |
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
A11-3 (+B) - Body ground |
Ignition switch off |
11 to 14 V |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
3. |
CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - BLOWER MOTOR WITH FAN SUB-ASSEMBLY) |
(a) Disconnect the I49 air conditioning amplifier assembly connector.
(b) Disconnect the A11 blower motor with fan sub-assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
I49-21 (BLW) - A11-2 (SI) |
Always |
Below 1 Ω |
|
I49-21 (BLW) or A11-2 (SI) - Other terminals and body ground |
Always |
10 kΩ or higher |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
4. |
CHECK BLOWER MOTOR WITH FAN SUB-ASSEMBLY |
(a) Connect the A11 blower motor with fan sub-assembly connector.
|
(b) Disconnect the I49 air conditioning amplifier assembly connector. |
|
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
I49-21 (BLW) - Body ground |
Always |
4.75 to 5.25 V |
| NG |
|
|
|
5. |
CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY |
(a) Connect the I49 air conditioning amplifier assembly connector.
(b) Using an oscilloscope, check the waveform.
|
*a |
Component with harness connected (Air Conditioning Amplifier Assembly) |
- |
- |
|
Item |
Content |
|---|---|
|
Terminal No. |
I49-21 (BLW) - I49-17 (GND) |
|
Tool Setting |
2 V/DIV., 1 ms./DIV. |
|
Condition |
|
HINT:
The waveform varies with the blower speed.
OK:
Waveform is similar to that shown in the illustration.
| OK |
|
| NG |
|
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY
|
![2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; HEATING / AIR CONDITIONING: AIR CONDITIONING AMPLIFIER: REMOVAL](/t3Portal/stylegraphics/info.gif)
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