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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 (When Not Using Hand-Held Tester) >> 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. INSPECT SEAT MEMORY SWITCH 
    1. Inspect 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
    G03386956Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE SEAT MEMORY SWITCH 
    2. OK: GO TO NEXT STEP. 
  4. 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
    G03386957Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 
    2. OK: GO TO NEXT STEP. 
  5. REPLACE MULTIPLEX NETWORK DOOR ECU FRONT RH 
    1. Exchange the driver's door ECU with new one and check that no malfunction exists in all the relative data to the memory.
    1. NG: CHECK AND REPLACE POSITION CONTROL ECU ASSY 
    2. OK: REPLACE MULTIPLEX NETWORK DOOR ECU FRONT