Toyota Sienna Service Manual: System description
1. GENERAL DESCRIPTION
- The power seat control system is equipped with the following function:
- The front seats are equipped with electric adjuster slide, reclining, lifter, front vertical and lumbar support adjustment functions.
- The power seat control system (w/ memory) is equipped with the following functions:
- Individual seat positions for two different drivers can be stored for the slide, reclining, front vertical and lifter.
- Similarly, power mirror positions for two different drivers can be stored. These are stored/restored together with the seat positions by pushing the seat memory switch.
- The above operations are performed using the multiplex communication system.
- As a safety precaution, the system does not allow seat position restoration unless the ignition switch is in the ON position and the shift lever is in the P position.
- Manual adjustment of the lumbar support
function can be performed even when the
position control ECU and switch assembly
(power seat control switch and ECU) is not
functional.
When the power seat control switch is operated, a command signal is sent to the position control ECU and switch assembly (power seat control switch and ECU). The position control ECU and switch assembly (power seat control switch and ECU) then activates the appropriate seat motor as needed.
This memory system does not use a seat position sensor. The seat position is detected by counting pulses that are output when the motor turns. The position control ECU and switch assembly (power seat control switch and ECU) is designed so that a malfunction of the seat memory system will not interfere with seat control. The seat memory switch also sends signals to the position control ECU and switch assembly (power seat control switch and ECU) to memorize a given seat position. Two seat positions can be memorized. The seat memory switch is later used to send signals to the position control ECU and switch assembly (power seat control switch and ECU) to return the seat to either of the memorized positions.
2. FUNCTION OF MAIN COMPONENT (w/ MEMORY)
- The following functions are available.
|
Components |
Function |
| Seat slide motor | Slides the driver side seat back and forth based on signals from the position control ECU and switch assembly (power seat control switch and ECU). |
| Seat reclining motor | Reclines the driver side seat back and forth based on signals from the position control ECU and switch assembly (power seat control switch and ECU). |
| Seat front vertical motor | Moves the front part of the driver side seat cushion up and down based on signals from the position control ECU and switch assembly (power seat control switch and ECU). |
| Seat lifter motor | Moves the driver side seat cushion up and down based on signals from the position control ECU and switch assembly (power seat control switch and ECU). This motor operates, and driver side seat rear vertical raises and lowers, and driver side seat rear vertical raises and lowers. |
| Set switch Memory switch | When the set and memory switches are pressed simultaneously, SET, 1
or 2 switch signal is input to the
power window regulator switch assembly (power window master switch) and
sends the seat memory
switch signal via the multiplex communication system.
When only the memory switch is pressed, SET, 1 or 2 switch signal is input to power window regulator switch assembly (power window master switch) and driver side seat position changes according to memory. |
| Lumbar support adjuster motor | Receives signal from lumber front power seat switch, motor operates, and lumber support can be adjusted |
| Front power seat switch (reclining, lifter, slide, front vertical) | Based on switches operated, seat adjuster signals are input into position control ECU and seat is adjusted accordingly |
| Lumbar front power seat switch | Based on switches operated, seat is adjusted accordingly |
3. SYSTEM OPERATION
- The front power seats adjustment and position memory are shown in the chart below
*: with Seat Position Memory System In the memory function, the memory switch operation signal is transferred from the outer mirror control ECU LH to the position control ECU and switch assembly (power seat control switch and ECU) via the multiplex communication line. Then, either the seat position is stored in memory or the previously stored seat position is recalled to set the appropriate seat position.
Precaution
1. GENERAL PRECAUTION
When using the battery during inspection, do not
bring the positive and negative tester probes too
close to each other as a short circuit may occur.
PARTS LOCATI ...
How to proceed with
troubleshooting
HINT:
Use this procedure to troubleshoot the front power seat
control system.
The intelligent tester should be used in steps 3 and 5.
1 VEHICLE BROUGHT TO WORKSHOP
2 CUSTOMER P ...
Other materials:
Transfer oil
ON-VEHICLE INSPECTION
1. INSPECT TRANSFER OIL
(a) Remove the No. 1 plug and gasket.
(b) Check the oil level is within 0 - 5 mm (0 - 0.20 in.)
below the lowest end of the hole for No. 1 plug.
NOTICE:
When changing oil, recheck the oil level after
driving.
Excessively large or small ...
Removal
1. BOLT, SCREW AND NUT TABLE
The bolts, the screws and the nuts, which are
necessary for installation and removal of the
instrument panel are shown in the illustration below
with alphabets.
2. DISCONNECT BATTERY NEGATIVE TERMINAL
3. REMOVE STEERING WHEEL COVER LOWER NO.2
4. ...
Checking and replacing
fuses
If any of the electrical components do not operate, a fuse may
have blown. If this happens, check and replace the fuses as necessary.
Turn the engine switch to the “LOCK” position (vehicles without a
smart key system) or off (vehicles with a smart key system).
Open the fuse box cover.
...
