Toyota 4Runner: Power Seat Position is not Memorized

Toyota 4Runner Service Manual / Vehicle Interior / Seat / Front Power Seat Control System(w/ Memory) / Power Seat Position is not Memorized

DESCRIPTION

When the seat memory SET switch and a memory switch (M1 or M2) are pressed simultaneously, the main body ECU commands the position control ECU through CAN communication to record the value of each position sensor.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

The front power seat control system (w/ Memory) uses the CAN communication system. First, confirm that there are no malfunctions in the communication system by checking the communication function of the CAN communication system (See page ).

PROCEDURE

1.	CHECK FRONT POWER SEAT CONTROL FUNCTION

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

OK:

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

GO TO PROBLEM SYMPTOMS TABLE

2.	READ VALUE USING TECHSTREAM (SEAT POSITION MEMORY)

(a) Use the seat memory switch to record the seat position (See page ).

NOTICE:

The seat position will not be recorded if the SET switch and both memory switches are pressed simultaneously.
If a memorizing operation has failed, release all switches. The seat memory function does not operate unless the switches are released.

(b) Using the Techstream, read the Data List (See page ).

Driver Seat

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Seat Memory No1	Seat position memorized with M1 switch / Mem or Not Mem	Mem: Memorized Not Mem: Not memorized	-
Seat Memory No2	Seat position memorized with M2 switch / Mem or Not Mem	Mem: Memorized Not Mem: Not memorized	-

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Seat Memory No1

Seat position memorized with M1 switch / Mem or Not Mem

Mem: Memorized

Not Mem: Not memorized

Seat Memory No2

Seat position memorized with M2 switch / Mem or Not Mem

Mem: Memorized

Not Mem: Not memorized

OK:

"Mem" is displayed on the tester.

END (USE SIMULATION METHOD TO CHECK)

3.	INSPECT SEAT MEMORY SWITCH

(a) Remove the seat memory switch (See page
).

(b) Inspect the seat memory switch (See page
).

REPLACE SEAT MEMORY SWITCH

4.	CHECK HARNESS AND CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) - SEAT MEMORY SWITCH)

(a) Disconnect the F9 main body ECU (multiplex network body ECU) connector.

(b) Disconnect the h3 seat memory switch connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
F9-23 (M1) - h3-3 (M1)	Always	Below 1 Ω
F9-6 (M2) - h3-4 (M2)	Always	Below 1 Ω
F9-12 (MM) - h3-2 (MRY)	Always	Below 1 Ω
F9-23 (M1) - Body ground	Always	10 kΩ or higher
F9-6 (M2) - Body ground	Always	10 kΩ or higher
F9-12 (MM) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.	REPLACE FRONT POWER SEAT SWITCH LH

(a) Replace the front power seat switch LH (See page ).

(b) Perform the memory operation (See page ).

OK:

Memory operation is normally.

END (FRONT POWER SEAT SWITCH LH WAS DEFECTIVE)

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

Front Power Seat does not Operate with Front Power Seat Switch

DESCRIPTION When a signal is input into the front power seat switch LH (position control ECU), the ECU manages the signals received from the front power seat switch LH and operates each motor. Wh ...

Front Power Seat Control System(w/o Memory)

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