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Circuit Opening Relay: 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. REMOVE RELAY BOX COVER 
  2. REMOVE CIRCUIT OPENING RELAY (Marking: C/OPN) 
    Fig 1: Identifying Circuit Opening Relay
    G00920353Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. INSPECT CIRCUIT OPENING RELAY CONTINUITY 
    1. Using an ohmmeter, check that there is a continuity between terminal 1 and 2.

      If there is no continuity, replace the relay.

    2. Check that there is no continuity between terminals 3 and 5.

      If there is a continuity, replace the relay.

    Fig 2: Checking Circuit Opening Relay Continuity
    G00920354Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. INSPECT CIRCUIT OPENING RELAY OPERATION 
    1. Apply the battery positive voltage across terminal 1 and 2.
    2. Using an ohmmeter, check that there is a continuity between terminal 3 and 5.

      If there is no continuity, replace the relay.

    Fig 3: Checking Circuit Opening Relay Operation
    G00920355Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. REINSTALL CIRCUIT OPENING RELAY 
  6. REINSTALL RELAY BOX COVER 
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