2003 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

Section 536 (Power Mirror Control System): Inspection

WARNING: This page is about a different car, the 2004 Lexus LX 470. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT LEFT SIDE MIRROR SWITCH CONTINUITY 
    LEFT SIDE MIRROR SWITCH CONTINUITY

    Switch position Tester connection Specified condition
    OFF - No continuity
    UP 3 - 4
    1 - 7 - 8    		 Continuity
    DOWN 1 - 3 - 8
    4 - 7    		 Continuity
    LEFT 4 - 9
    1 - 7 - 8    		 Continuity
    RIGHT 4 - 7
    1 - 8 - 9    		 Continuity

    If the continuity is not as specified, replace the switch.

    If the continuity is as specified, inspect the switch circuit.

  2. INSPECT RIGHT SIDE MIRROR SWITCH CONTINUITY 
    RIGHT SIDE MIRROR SWITCH CONTINUITY

    Switch position Tester connection Specified condition
    OFF - No continuity
    UP 2 - 4
    1 - 7 - 8    		 Continuity
    DOWN 4 - 7
    1 - 2 - 8    		 Continuity
    LEFT 4 - 10
    1 - 7 - 8    		 Continuity
    RIGHT 4 - 7
    1 - 8 - 10    		 Continuity
    Fig 1: Identifying Adjustment, Retract & Mirror Switch
    G03485973Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If the continuity is not as specified, replace the switch.

    If the continuity is as specified, inspect the switch circuit.

  3. INSPECT RETRACT SWITCH CONTINUITY 
    RETRACT SWITCH CONTINUITY

    Switch position Tester connection Specified condition
    RETURN 1 - 5
    2 - 4    		 Continuity
    RETRACT 1 - 2
    4 - 5    		 Continuity

    If the continuity is not as specified, replace the switch.

    If the continuity is as specified, inspect the switch circuit.

    Fig 2: Identifying Retract Switch Terminals
    G03485974Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. INSPECT MIRROR SWITCH CIRCUIT 

    Disconnect the connector from the switch and inspect the connector on the wire harness side.

    Fig 3: Inspecting Mirror Switch Circuit
    G03485975Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    MIRROR SWITCH CIRCUIT SPECIFIED CONDITION

    Tester connection Condition Specified condition
    8 - Ground Always Continuity
    4 - Ground Ignition switch position LOCK No voltage
    4 - Ground Ignition switch position ACC or ON Battery positive voltage

    If the circuit is not as specified, inspect the circuits connected to other parts.

  5. INSPECT INDICATOR LIGHT OPERATION 

    Connect the battery positive (+) lead to terminal 5 and the battery negative (-) lead to terminal 6. If the indicator light does not come on, replace the switch.

    Fig 4: Inspecting Indicator Light Operation
    G03485976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. INSPECT MIRROR MOTOR OPERATION 
    1. Connect the battery positive (+) lead to terminal 8 and the battery negative (-) lead to terminal 7, and check that the mirror turns to the left side.
      Fig 5: Identifying Mirror Motor Terminal 7 & 8 Connection To Battery (Left Side)
      G03485977Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Reverse the polarity, and check that the mirror turns to the right side.
      Fig 6: Identifying Mirror Motor Terminal 7 & 8 Connection To Battery (Right Side)
      G03485978Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Connect the battery positive (+) lead to terminal 6 and the battery negative (-) lead to terminal 7, and check that the mirror turns upward.
      Fig 7: Identifying Mirror Motor Terminal 6 & 7 Connection To Battery (Upward)
      G03485979Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Reverse the polarity, and check that the mirror turns downward.
      Fig 8: Identifying Mirror Motor Terminal 6 & 7 Connection To Battery (Downward)
      G03485980Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If operation is not as specified, replace the mirror assembly.

  7. w/ Driving Position Memory only: INSPECT MIRROR POSITION SENSORS OPERATION 

    HINT:

    Strip off the vinyl tape on the connector and remove terminal 7, 9, 10, 15 and 16 from the connector housing.

    1. Connect a series of three 1.5 V dry cell batteries.
    2. Connect the positive (+) lead from the dry cell batteries to terminal 9 and its negative (-) lead to terminal 15.
    3. Connect the voltmeter positive (+) lead to terminal 16 and the voltmeter negative (-) lead to terminal 15.
    4. Apply battery positive voltage to terminal 7 and 6, then check that the voltage gradually changes as shown in MIRROR POSITION SPECIFICATION  while the mirror moves between the upper most position and the lower most position.
      Fig 9: Inspecting Mirror Position Sensors Operation (Lower Move)
      G03485981Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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