Last Modified: 11-29-2007 1.6 J
Service Category: Vehicle Interior Section: Seat
Model Year: 2008 Model: Sequoia Doc ID: RM000002RB2008X
Title: SEAT: FRONT POWER SEAT CONTROL SYSTEM (w/ Memory): DESCRIPTION (2008 Sequoia)

Power Seat Position is not Memorized

DESCRIPTION

When the seat memory SET switch and a seat memory switch (seat memory switch 1 or seat memory switch 2) are pressed simultaneously, the outer mirror control ECU commands the position control ECU and switch through CAN communication to record each position value.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1.

CHECK DTC

(a) Use the Techstream to check if the CAN communication system is functioning normally NETWORKING: CAN COMMUNICATION SYSTEM: DIAGNOSIS SYSTEM (2008 Sequoia) .

Result

Result

Proceed to

CAN DTC is not output

A

CAN DTC is output

B
A

2.

CHECK FRONT POWER SEAT CONTROL FUNCTION

(a) Check that each function of the power seat operates normally by using the front power seat switches.

OK:

Each function of power seat operates normally by using seat switches.

OK

3.

CHECK SEAT MEMORY SWITCH FUNCTION

(a) Perform a memory operation properly. Check that the buzzer sounds to indicate the completion of the memory operation.

NOTICE:

  • The seat position will not be recorded if the seat memory SET switch and 2 or more of the seat memory switches (for example, seat memory switch 1 and seat memory switch 2) are pressed simultaneously.
  • If a memorizing operation has failed, release all switches. The seat memory function does not operate unless the switches are released.

OK:

Seat memory switch function operates normally.

OK

4.

READ VALUE USING TECHSTREAM (PARK/NEUTRAL POSITION SWITCH)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream ON.

(d) Enter the following menus: Powertrain / ECT / Data List.

(e) According to the display on the Techstream, read the Data List.

ECT

Tester Display

Measurement Item/Display

Normal Condition

Diagnostic Note

Shift SW Status (P Range)

PNP switch status / ON or OFF

ON: Shift lever in P

OFF: Shift lever not in P

-

OK:

On the Techstream screen, each item changes between ON and OFF according to above chart.

Result

Result

Proceed to

OK

A

NG (A750E automatic transmission)

B

NG (A750F automatic transmission)

C

NG (AB60E automatic transmission)

D

NG (AB60F automatic transmission)

E
A

5.

READ VALUE USING TECHSTREAM (SEAT MEMORY SWITCH)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream ON.

(d) Enter the following menus: Body Electrical / Driver Seat / Data List.

(e) According to the display on the Techstream, read the Data List.

Driver Seat

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

SET Switch

Seat memory SET switch signal / ON or OFF

ON: Seat memory SET switch on

OFF: Seat memory SET switch off

-

M1 Switch

Seat memory switch 1 signal / ON or OFF

ON: Seat memory switch 1 on

OFF: Seat memory switch 1 off

-

M2 Switch

Seat memory switch 2 signal / ON or OFF

ON: Seat memory switch 2 on

OFF: Seat memory switch 2 off

-

OK:

On the Techstream screen, each item changes between ON and OFF according to above chart.

OK

6.

INSPECT SEAT MEMORY SWITCH

(a) Remove the seat memory switch SEAT: SEAT MEMORY SWITCH: REMOVAL (2008 Sequoia) .

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

1 (MRY) - 4 (E)

Seat memory SET switch pressed

Below 1 Ω

Seat memory SET switch not pressed

10 kΩ or higher

2 (M1) - 4 (E)

Seat memory switch 1 pressed

Below 1 Ω

Seat memory switch 1 not pressed

10 kΩ or higher

3 (M2) - 4 (E)

Seat memory switch 2 pressed

Below 1 Ω

Seat memory switch 2 not pressed

10 kΩ or higher
OK

7.

CHECK HARNESS AND CONNECTOR (OUTER MIRROR CONTROL ECU - SEAT MEMORY SWITCH)

(a) Disconnect the M8 ECU connector.

(b) Disconnect the M6 switch connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

M8-7 (M2) - M6-3 (M2)

Always

Below 1 Ω

M8-7 (M2) - Body ground

Always

10 kΩ or higher

M8-8 (M1) - M6-2 (M1)

Always

Below 1 Ω

M8-8 (M1) - Body ground

Always

10 kΩ or higher

M8-9 (MM) - M6-1 (MRY)

Always

Below 1 Ω

M8-9 (MM) - Body ground

Always

10 kΩ or higher

M8-10 (MSWE) - M6-4 (E)

Always

Below 1 Ω

M8-10 (MSWE) - Body ground

Always

10 kΩ or higher
OK

8.

CHECK OUTER MIRROR CONTROL ECU OPERATION

(a) After replacing the outer mirror control ECU, check that the front power seat control functions operate normally using the front seat switches and seat memory switch.

OK:

Front power seat control functions operate normally.

OK