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Home >> Lexus >> 2007 >> LX 470 >> Repair and Diagnosis >> Engine Performance >> Engine Control System (2UZ-FE) >> Ignition Relay No. 1 >> On-Vehicle Inspection
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On-Vehicle Inspection

HINT:

The IG1 NO. 1 relay is built in the engine room junction block. Since the relay is constructed with a relay block that is in the junction block as a unit, it is impossible to disconnecting the wire harness connecting with the relay block.

If the relay has a malfunction, replace it with the junction block assembly wire harness together.

  1. CHECK ENGINE ROOM JUNCTION BLOCK (IG1 NO. 1) 
    1. Disconnect the engine room relay block from the vehicle body.
      Fig 1: Identifying Engine Room Relay Block
      G05196940Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the continuity of the relay.

      OK 

      CONTINUITY REFERENCE

      Always Tester Connection Specified Condition
      Constant 1B-50 - 1B-40 Continuity
      Apply B+ between terminals 1B-50 - 1B-40 1C-2 - 1B-47 Continuity

      If the continuity is not as specified, replace the engine room junction block.

    3. Install the engine room relay block to the vehicle body.
  2. CHECK IG1 NO. 2 RELAY (Marking: IG1 NO. 2) 
    1. Remove the relay from the cowl side junction block LH.
      Fig 2: Identifying Cowl Side Junction Block LH
      G05196941Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance of the relay.

      Standard resistance 

      RESISTANCE SPECIFICATION

      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.

    3. Install the relay.
      Fig 3: Relay Circuit Diagram
      G04949647Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. CHECK IG1 NO. 3 RELAY (Marking: IG1 NO. 3) 
    1. Remove the relay from the cowl side junction block RH.
    2. Measure the resistance of the relay.

      Standard resistance 

      RESISTANCE SPECIFICATION

      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.

    3. Install the relay.
      Fig 4: Relay Circuit Diagram
      G04949647Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002