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Home >> Lexus >> 2002 >> SC 430 >> Repair and Diagnosis >> Body & Frame >> Seats >> Front Power Seat Control System (W/Memory) - Diagnosis >> Position Cannot Be Memorized >> Inspection Procedure
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Inspection Procedure

  1. FUNCTION CHECK (OPERATION) 
    1. Check that manual operations via the power seat switch work normally.
    1. NG: FLOW CHART 1 
    2. OK: GO TO NEXT STEP. 
  2. FUNCTION CHECK (MEMORY) 
    1. Perform a memorizing operation properly, and then check whether the memory functions normally and the buzzer sounds to inform the memorizing operation has done.
    NOTE:
    • The memory does not function when the SET, M1 and M2 are simultaneously pressed.
    • In case of mis-operation, the memory does not function unless the setting once turned off.
    1. OK: NORMALITY 
    2. NG: GO TO NEXT STEP. 
  3. READ VALUE OF LEXUS HAND-HELD TESTER 
    1. Connect the LEXUS hand-held tester to the DLC3.
    2. Read DATA MONITOR Using hand-held tester.

    SEAT ECU 

    STANDARD CONDITION CHART

    Item Condition Standard condition
    SLIDE SW FRONT SLIDE SEAT SW CENTER --> FRONT ON/OFF
    SLIDE SW REAR SLIDE SEAT SW CENTER --> REAR ON/OFF
    R VTCL SW UP REAR SW CENTER --> UP ON/OFF
    R VTCL SW DOWN REAR SW CENTER --> DOWN ON/OFF
    F VTCL SW UP REAR SW CENTER --> UP ON/OFF
    F VTCL SW DOWN REAR SW CENTER --> DOWN ON/OFF
    RECLIN SW FRONT RECLINING SW CENTER --> FRONT ON/OFF
    RECLIN SW REAR RECLINING SW CENTER --> REAR ON/OFF
    SEAT MEM M1 IG ON.P RANGE PRESS SET SW AND M1 SW MEM/NOT MEM
    SEAT MEM M 2 IG ON.P RANGE PRESS SET SW AND M2 SW MEM/NOT MEM
    MEM M1 SW IG ON.P RANGE PRESS M1 SW MEM/NOT MEM
    MEM M2 SW IG ON.P RANGE PRESS M2 SW MEM/NOT MEM
    D-MIRR MEM M1 IG ON.P RANGE PRESS M1 SW MEM/NOT MEM
    D-MIRR MEM M2 IG ON.P RANGE PRESS M2 SW MEM/NOT MEM
    P-MIRR MEM M2 IG ON.P RANGE PRESS M1 SW MEM/NOT MEM
    P-MIRR MEM M2 IG ON.P RANGE PRESS M2 SW MEM/NOT MEM
    SET SW SET SW ON/OFF ON/OFF
    M1 SW M1 SW ON/OFF ON/OFF
    M2 SW M2 SW ON/OFF ON/OFF
    IG SW IG SW ON ON/OFF
    KEY UNLOOK SW LOOK/UNLOOK ON/OFF
    D-DOOR WARN SW CTY SW ON ON/OFF
    PNP SW P RANGE ON/OFF
    1. When "Seat Memory Switch" does not work, proceed to "A".
    2. When all items work or all items except "seat memory switch" work, proceed to "B".
    1. B: CHECK AND REPLACE POSITION CONTROL ECU ASSY (See  TERMINALS OF ECU  ) 
    2. A: GO TO NEXT STEP. 
  4. INSPECT SEAT MEMORY SWITCH 
    1. Inspect the front power seat switch continuity.

    Memory switch: 

    TESTER CONNECTION CHART

    Switch condition Tester connection Specified condition
    M1 switch pressed 1-3 Continuity
    M2 switch pressed 1-4 Continuity
    SET switch pressed 1-2 Continuity
    Fig 1: Inspecting Front Power Seat Switch Continuity
    G03386954Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE SEAT MEMORY SWITCH 
    2. OK: GO TO NEXT STEP. 
  5. CHECK WIRE HARNESS 
    1. Check the continuity of the wire harness between the seat memory switch and door ECU.
    TESTER CONNECTION CHART

    Tester connection Condition Specified condition
    Switch 1 <--> D18-23 Constant Continuity
    Switch 2 <--> D18-24 Constant Continuity
    Switch 3 <--> D18-16 Constant Continuity
    Switch 4 <--> D18-15 Constant Continuity
    Fig 2: Checking Continuity Of Wire Harness Between Seat Memory Switch & Door ECU
    G03386955Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 
    2. OK: GO TO NEXT STEP. 
  6. REPLACE COMPUTER, MULTIPLEX NETWORK DOOR, FR LH 
    1. Exchange the driver's door ECU with new one. Or, check that no malfunction exists in all the relative data to the memory by carrying out a data monitor of the driver's door ECU by using the temporarily installed passenger's door ECU.
    1. NG: CHECK AND REPLACE POSITION CONTROL ECU ASSY (See  TERMINALS OF ECU  ) 
    2. OK: REPLACE COMPUTER, MULTIPLEX NETWORK DOOR, FR 
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