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Home >> Lexus >> 2008 >> SC 430 >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> Ignition Relay No. 1 >> On-Vehicle Inspection
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On-Vehicle Inspection

  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL 
    CAUTION: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
  2. REMOVE IG1 RELAY 
    1. Remove the IG1 relay from the instrument panel junction block.
  3. INSPECT RELAY 
    1. Measure resistance of the IG1 relay.

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Specified Condition
    3-5 10 kΩ or higher
    3-5 Below 1 Ω (when battery voltage is applied to terminals 1 and 2)

    If the result is not as specified, replace the relay.

    Fig 1: IG1 Relay Circuit Diagram
    G05838989Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. INSTALL IG1 RELAY 
  5. CONNECT CABLE TO NEGATIVE BATTERY TERMINAL 
  6. PERFORM INITIALIZATION 
    1. Perform initialization (see INITIALIZATION ).
    NOTE: Certain systems need to be initialized after disconnecting and reconnecting the cable from the negative (-) battery terminal.