Toyota Tundra Service Manual: 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 via CAN communication. If the seat memory SET switch is being pressed when one of the M1or M2 switches is pressed, or if either of the M1 or M2 switches is pressed within 3 seconds of pressing the seat memory SET switch, the main body ECU (multiplex network body ECU) sends a memory request signal to the position control ECU and switch assembly. After receiving the request signal, the position control ECU and switch assembly memorizes the location data of each motor.

WIRING DIAGRAM

PROCEDURE

(a) Use the Techstream to check if the CAN communication system is functioning normally (See page ).

OK:

CAN communication DTC is not output.

NG

Go to CAN COMMUNICATION SYSTEM

OK

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

OK:

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

NG

Go to PROBLEM SYMPTOMS TABLE

OK

(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) Read the Data List according to the display on the Techstream.

OK:

ON or OFF is displayed on the Techstream according to the table above.

NG

GO TO STEP 9

OK

(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 / Active Test.

(e) Perform the Active Test according to the display on the Techstream.

OK:

Buzzer sounds normally.

NG

REPLACE POSITION CONTROL ECU AND SWITCH ASSEMBLY

OK

(a) Temporarily replace the outer mirror ECU assembly with a new or normally functioning one (See page ).

NEXT

(a) Perform a memory operation and check that the buzzer sounds to indicate the completion of the memory operation (See page ).

NOTICE:

• The seat position will not be recorded if the SET switch and 2 seat 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.

OK:

Seat position memory function operates normally.

OK

END (OUTER MIRROR CONTROL ECU ASSEMBLY WAS DEFECTIVE)

NG

(a) Temporarily replace the position control ECU and switch assembly with a new or normally functioning one (See page ).

NEXT

(a) Perform a memory operation and check that the buzzer sounds to indicate the completion of the memory operation (See page ).

NOTICE:

• The seat position will not be recorded if the SET switch and 2 seat 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.

OK:

Seat position memory function operates normally.

OK

END (POSITION CONTROL ECU AND SWITCH ASSEMBLY WAS DEFECTIVE)

NG

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

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

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

NG

REPLACE SEAT MEMORY SWITCH

OK

(a) Disconnect the N14 outer mirror control ECU assembly connector.

(b) Disconnect the N6 seat memory switch connector.

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

Standard Resistance:

OK

REPLACE OUTER MIRROR CONTROL ECU ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR