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:
Inspection
1. INSPECT VENTILATION VALVE
(a) Install a clean hose to the ventilation valve.
(b) Check the ventilation valve operation.
(1) Blow air into the cylinder head side, and check
that air passes through easily.
NOTICE:
Do not suck air through the valve.
Petroleum substances i ...
Pressure Control Solenoid "A" Electrical (Shift
Solenoid Valve SL1)
DESCRIPTION
Shifting from 1st to 5th is performed in combination with "ON" and "OFF"
operation of the shift solenoid
valves SL1, SL2, SL3, S4 and SR which are controlled by the ECM. If an open or
short circuit occurs in
either of the shift solenoid valves, the ECM cont ...
Problem symptoms table
POWER BACK DOOR SYSTEM
Symptom
Suspected Area
Power back door does not operate when switch* is
pressed (* Switch indicates the satellite switch for
power back door)
ECU-B fuse
Power back door main switch
Satellite switch
Power back door tou ...
