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System Operation Check

  1. Trouble shooting of a power seat system complaint begins with verification of the customer problem. Perform the Customer Problem Analysis Check (Power Seat Control System). See Fig 1.
  2. Determine and confirm symptom. See POWER SEAT PROBLEM SYMPTOMS . Without applicable symptoms, go to step  3. With applicable symptoms, go to step  4.
    POWER SEAT PROBLEM SYMPTOMS

    Symptom Suspected Area
    Both Manual & Return Functions Do Not Operate (All Functions) Power Source Circuit (1), Power Seat Control Switch Circuit (2), Seat Position Control ECU (3) Or Wiring Harness
    Both Manual & Return Functions Do Not Operate (One Function Only) Motor Circuit (4), Seat Position Control ECU (3), Seat Position Motor (5)Or Wiring Harness
    One Or All Functions Do Not Operate For Manual Operation Only Power Seat Control Switch Circuit (2), Seat Position Control ECU (3) Or Wiring Harness
    Memory Function Does Not Operate Power Seat Memory Switch Circuit (6), Ignition Switch Circuit, Park/Neutral Position Switch Circuit (7), Seat Position Control ECU Or Wiring Harness
    Only Return Function Does Not Operate Or Operates A Little, Then Stops (All Return Functions) Seat Position Control ECU (3)
    Only Return Function Does Not Operate Or Operates A Little, Then Stops (Only One Return Function) Seat Position Control ECU (3) Or Power Seat Motor (5)
    Power Seat Does Not Operate Front Power Seat Switch (5), PWR SEAT Fuse Or Wiring Harness
    Power Seat Does Not Slide Front Power Seat Switch (5), Front Slide Power Seat Motor Assembly (Slide) (5) Or Wiring Harness
    Front Vertical Of Power Seat Does Not Operate (Driver's Seat Only) Front Power Seat Switch (5), Front Up/Down Power Seat Motor Assembly (Front Vertical) (5) Or Wiring Harness
    Rear Lifter Of Power Seat Does Not Operate (Driver's Seat Only) Front Power Seat Switch (5), Power Seat Motor Assembly (Rear Vertical) (5) Or Wiring Harness
    Power Seat Does Not Recline Front Power Seat Switch (5), Power Seat Motor Assembly (Reclining) (5) Or Wiring Harness
    Lumbar Support Does Not Operate (Driver's Seat Only) Front Power Seat Switch (5), Power Seat Motor Assembly (Lumbar Support) (5) Or Wiring Harness
    Seat Heaters Do Not Operate SEAT HTR 20A Fuse, Front Seat Cushion Heater Assembly (8), Front Seat Back Heater Assembly (8), Heater Control Housing Sub-Assembly (A/C Amplifier) (9) Or Wiring Harness
    (1) See POWER SOURCE CIRCUIT  under COMPONENT TESTS.
    (2) See POWER SEAT CONTROL SWITCH CIRCUIT  under COMPONENT TESTS.
    (3) Inspect connector, check for open or short circuit, and check and replace ECU.
    (4) See POWER SEAT MOTOR CIRCUIT  under COMPONENT TESTS.
    (5) See POWER SEAT INSPECTION  under COMPONENT TESTS.
    (6) See MEMORY SWITCH CIRCUIT  under COMPONENT TESTS.
    (7) See DIAGNOSIS - U150E under AUTOMATIC TRANSMISSION article in TRANSAXLE/TRANSMISSION.
    (8) See SEAT HEATER INSPECTION  under COMPONENT TESTS.
    (9) See DTC 63: SEAT HEATER CIRCUIT (DRIVER SIDE)  or DTC 64: SEAT HEATER CIRCUIT (PASSENGER SIDE)  under DIAGNOSTIC TESTS.
  3. Perform trouble shooting in the following method, depending on the malfunction symptom.
  4. Perform necessary adjustments, repairs or replacements.
  5. Perform a confirmation test. See CONFIRMATION TEST .
Fig 1: Customer Problem Analysis Check (Power Seat Control System)
G00176339Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002