| Last Modified: 08-21-2023 | 6.11:8.1.0 | Doc ID: RM100000001APTB |
| Model Year Start: 2019 | Model: Avalon | Prod Date Range: [04/2018 - ] |
| Title: SEAT: FRONT POWER SEAT CONTROL SYSTEM (for Gasoline Model with Memory): Power Seat Position is not Memorized; 2019 - 2022 MY Avalon [04/2018 - ] | ||
|
Power Seat Position is not Memorized |
DESCRIPTION
The main body ECU (multiplex network body ECU) receives seat memory switch signals from the outer mirror control ECU assembly LH via CAN communication. If the SET switch is being pressed when one of the M1 or M2 switches is pressed, or if one of the M1 or M2 switches is pressed within 3 seconds of pressing the SET switch, the main body ECU (multiplex network body ECU) sends a memory request signal to the position control ECU assembly. After receiving the request signal, the position control ECU assembly memorizes the location data of each motor.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
-
The seat position will not be stored if the SET switch and 2 or more of the seat memory switches (for example, M1 switch and M2 switch) are pressed simultaneously.
If a memorizing operation has failed, release all of the switches. The seat memory function will not operate unless the switches are released.
-
The seat will not return to the memorized position if 2 or more of the seat memory switches (for example, M1 switch and M2 switch) are pressed simultaneously.
If a restoring operation has failed, release all of the switches. The seat memory restoring function will not operate unless the switches are released.
-
The front power seat control system (w/ Memory) uses the CAN communication system. First, confirm that there are no malfunctions in the CAN communication system. Refer to How to Proceed with Troubleshooting.
Click here
![2019 - 2022 MY Avalon [04/2018 - ]; SEAT: FRONT POWER SEAT CONTROL SYSTEM (for Gasoline Model with Memory): HOW TO PROCEED WITH TROUBLESHOOTING](/t3Portal/stylegraphics/info.gif)
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Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
Click here
PROCEDURE
|
1. |
CHECK FRONT POWER SEAT CONTROL OPERATION |
(a) Check that each function of the power seat operates normally by using the front power seat switch LH.
Click here
OK:
Each function of the power seat operates normally using the front power seat switch LH.
| NG |
|
|
|
2. |
READ VALUE USING TECHSTREAM (SEAT MEMORY SWITCH) |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Mirror L / Data List.
(e) Read the Data List according to the display on the Techstream.
Body Electrical > Mirror L > Data List
|
Tester Display |
Measurement Item |
Range |
Normal Condition |
Diagnostic Note |
|---|---|---|---|---|
|
Seat Memory Switch1 |
M1 switch |
ON or OFF |
ON: M1 switch on OFF: M1 switch off |
- |
|
Seat Memory Switch2 |
M2 switch |
ON or OFF |
ON: M2 switch on OFF: M2 switch off |
- |
|
Seat Memory Set SW |
SET switch |
ON or OFF |
ON: SET switch on OFF: SET switch off |
- |
Body Electrical > Mirror L > Data List
|
Tester Display |
|---|
|
Seat Memory Switch1 |
|
Seat Memory Switch2 |
|
Seat Memory Set SW |
OK:
On the Techstream screen, ON or OFF is displayed accordingly.
| NG |
|
|
|
3. |
PERFORM ACTIVE TEST USING TECHSTREAM (BUZZER) |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Driver Seat / Active Test.
(e) Perform the Active Test according to the display on the Techstream.
Body Electrical > Driver Seat > Active Test
|
Tester Display |
Measurement Item |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
Buzzer |
Buzzer operation |
OFF/ON |
- |
Body Electrical > Driver Seat > Active Test
|
Tester Display |
|---|
|
Buzzer |
OK:
Buzzer sounds normally.
| NG |
|
REPLACE POSITION CONTROL ECU ASSEMBLY
|
|
|
4. |
REPLACE OUTER MIRROR CONTROL ECU ASSEMBLY LH |
(a) Replace the outer mirror control ECU assembly LH with a new or known good one.
Click here
|
|
5. |
CHECK SEAT POSITION MEMORY AND RESTORING FUNCTION |
(a) Check the seat position memory and restoring functions.
Click here
OK:
Seat position memory and restoring functions operate normally.
| OK |
|
END (OUTER MIRROR CONTROL ECU ASSEMBLY LH WAS DEFECTIVE) |
|
|
6. |
REPLACE POSITION CONTROL ECU ASSEMBLY |
(a) Replace the position control ECU assembly with a new or known good one.
Click here
|
|
7. |
CHECK SEAT POSITION MEMORY AND RESTORING FUNCTION |
(a) Check the seat position memory and restoring functions.
Click here
OK:
Seat position memory and restoring functions operate normally.
| OK |
|
END (POSITION CONTROL ECU ASSEMBLY WAS DEFECTIVE) |
| NG |
|
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)
|
|
8. |
INSPECT SEAT MEMORY SWITCH |
(a) Remove the seat memory switch.
Click here
(b) Inspect the seat memory switch.
Click here
| NG |
|
|
|
9. |
CHECK HARNESS AND CONNECTOR (OUTER MIRROR CONTROL ECU ASSEMBLY LH - SEAT MEMORY SWITCH - BODY GROUND) |
(a) Disconnect the I21 outer mirror control ECU assembly LH connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
I21-1 (MM) - I17-5 (MMRY) |
Always |
Below 1 Ω |
|
I21-1 (MM) or I17-5 (MMRY) - Body ground |
Always |
10 kΩ or higher |
|
I21-2 (M1) - I17-4 (1) |
Always |
Below 1 Ω |
|
I21-2 (M1) or I17-4 (1) - Body ground |
Always |
10 kΩ or higher |
|
I21-3 (M2) - I17-3 (2) |
Always |
Below 1 Ω |
|
I21-3 (M2) or I17-3 (2) - Body ground |
Always |
10 kΩ or higher |
|
I21-7 (GND) - Body ground |
Always |
Below 1 Ω |
|
I17-1 (E) - Body ground |
Always |
Below 1 Ω |
| OK |
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
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