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Section 639 (Power Source): 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 ENGINE ROOM RELAY BLOCK CIRCUIT 
    Fig 1: Identifying Engine Room Relay Block Circuit (1 Of 4)
    G03485739Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 2: Identifying Engine Room Relay Block Circuit (2 Of 4)
    G03485740Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 3: Identifying Engine Room Relay Block Circuit (3 Of 4)
    G03485741Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 4: Identifying Engine Room Relay Block Circuit (4 Of 4)
    G03485742Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the fuse from the relay block and inspect the connector on the relay block side.
      FUSE SPECIFIED CONDITION

      Fuse Tester connection Condition Specified condition
      TOWING 1 - Ground Always Battery positive voltage
      MIR HTR 3 - Ground Always Battery positive voltage
      RR HTR 5 - Ground Always Battery positive voltage
      HAZ-TRN 7 - Ground Always Battery positive voltage
      ALT-S 9 - Ground Always Battery positive voltage
      NV-IR 13 - Ground Always Battery positive voltage
      FRFOG 13 - Ground Always Battery positive voltage
      TOWING BRK 15 - Ground Always Battery positive voltage
      HEADCLNER 17 - Ground Ignition switch ON Battery positive voltage
      FR-IG 19 - Ground Ignition switch ON Battery positive voltage
      PANEL 21 - Ground Light control switch HEAD or TAIL Battery positive voltage
      TOWING TAIL 23 - Ground Light control switch HEAD or TAIL Battery positive voltage
      TAIL 25 - Ground Light control switch HEAD or TAIL Battery positive voltage
      BAT 29 - Ground Always Battery positive voltage
      TEL 31 - Ground Always Battery positive voltage
      AMP 33 - Ground Always Battery positive voltage
      EFI or ECD NO.1 35 - Ground Always Battery positive voltage
      AM2 37 - Ground Always Battery positive voltage
      ETCS 39 - Ground Always Battery positive voltage
      HORN 41 - Ground Always Battery positive voltage
      HEAD LH-UPR 51 - Ground Light control switch HI or Flash Battery positive voltage
      HEAD RH-UPR 49 - Ground Light control switch HI or Flash Battery positive voltage
      HEAD LH-LWR 47 - Ground Light control switch HEAD Battery positive voltage
      HEAD RH-LWR 45 - Ground Light control switch HEAD Battery positive voltage
      ST1 1 - Ground Always Battery positive voltage
      AHC 1 - Ground Always Battery positive voltage
      ABS NO.1 1 - Ground Always Battery positive voltage
      ABS NO.2 1 - Ground Always Battery positive voltage
      STARTER 1 - Ground Always Battery positive voltage

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

    2. Remove the relay from the relay block and inspect the connector on the relay block side.
      FUSE SPECIFIED CONDITION

      Relay Tester connection Condition Specified condition
      AHC 1 - Ground Ignition switch ON Battery positive voltage
      ABS SOL 1 - Ground Ignition switch ON Battery positive voltage
      ABS MTR1 1 - Ground Always Battery positive voltage
      ABS MTR2 1 - Ground Ignition switch ON Battery positive voltage
      STARTER 5 - Ground Always Continuity
      STARTER 2 - Ground Ignition switch ON Battery positive voltage
      EFI or ECD 3 - Ground Always Battery positive voltage
      COPN 5 - Ground Always Battery positive voltage
      COPN - Ground Ignition switch ON Continuity
      FP PUMP 2 - Ground Ignition switch ON Battery positive voltage
      FP PUMP 3 - Ground Ignition switch ON Continuity
      TR 5 - Ground Always Battery positive voltage
      HTR 1 - Ground Ignition switch ON Continuity

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

    3. Inspect Engine Room Relay Block Inner Circuit:

      Inspect the connector on the relay block side.

      HINT:

      Remove the relay block from the vehicle.

      FUSE SPECIFIED CONDITION

      Relay Tester connection Condition Specified condition
      IG1 NO.1 50(1B) - 40(1B) Always Continuity
      IG1 NO.1 50(1B) - 39(1B) Always Continuity
      IG1 NO.1 50(1B) - 45(1B) Always Continuity
      IG1 NO.1 50(1B) - 56(1B) Always Continuity
      IG1 NO.1 50(1B) - 55(1B) Always Continuity
      IG1 NO.1 50(1B) - 44(1B) Always Continuity
      IG1 NO.1 50(1B) - 43(1B) Always Continuity
      IG1 NO.1 50(1B) - 41 (1B) Always Continuity
      IG1 NO.1 50 (1B) - 42 (1B) Always Continuity
      IG1 NO.1 2(1C) - 47(1B) Apply B+ between terminals 50 (1B) and 40 (1B). Continuity
      IG1 NO.1 2 (1C) - 60(1 A) Apply B+ between terminals 50 (1B) and 40 (1B). Continuity
      IR HTR 50 (1B) - 48 (1B) Always Continuity
      MIR HTR 2(1C) - 66(1B) Apply B+ between terminals 50 (1B) and 48 (1B). Continuity
      RR HTR 50(1B) - 52(1B) Always Continuity
      RR HTR 50(1B) - 57(1B) Always Continuity
      RR HTR 2(1C) - 71 (1B) Apply B+ between terminals 50 (1B) and 52 (1B). Continuity
      RR HTR 70 (1B) - 71 (1B) Apply B+ between terminals 50 (1B) and 52 (1B). Continuity
      FR FOG 61 (1A) - 59(1B) Always Continuity
      FR FOG 2 (1C) - 62(1 A) Apply B+ between terminals 61 (1 A) and 59 (1B). Continuity
      FR FOG 2 (1C) - 64(1 A) Apply B+ between terminals 61 (1 A) and 59 (1B). Continuity
      TAIL 2(1C) - 49(1B) Always Continuity
      TAIL 2(1C)-51 (1A) Apply B+ between terminals 2 (1C) and 49 (1B). Continuity
      TAIL 2 (1C) - 50(1 A) Apply B+ between terminals 2 (1C) and 49 (1B). Continuity
      TAIL 2 (1C) - 59(1 A) Apply B+ between terminals 2 (1C) and 49 (1B). Continuity
      TAIL 2 (1C - 49(1 A) Apply B+ between terminals 2 (1C) and 49 (1B). Continuity
      TAIL 2 (1C) - 58(1 A) Apply B+ between terminals 2 (1C) and 49 (1B). Continuity
      TAIL 2(1C) - 60(1B) Apply B+ between terminals 2 (1C) and 49 (1B). Continuity
      TAIL 2(1C) - 58(1B) Apply B+ between terminals 2 (1C) and 49 (1B). Continuity
      TAIL 2(1C) - 67(1B) Apply B+ between terminals 2 (1C) and 49 (1B). Continuity
      TAIL 2(1C) - 69(1B) Apply B+ between terminals 2 (1C) and 49 (1B). Continuity
      PANEL 2(1C) - 64(1B) Apply B+ between terminals 2 (1C) and 49 (1B). Continuity
      EAD 1 (1C) - 22(1B) Always Continuity
      HEAD 1 (1C) - 33(1B) Apply B+ between terminals 1 (1C) and 22 (1B). Continuity
      HEAD 1 (1C) - 19(1A) Apply B+ between terminals 1 (1C) and 22 (1B). Continuity
      HEAD 1(1C) - 26(1A) Apply B+ between terminals 1 (1C) and 22 (1B). Continuity
      HEAD 1 (1C) - 28(1A) Apply B+ between terminals 1 (1C) and 22 (1B). Continuity
      HEAD 1 (1C) - 20(1A) Apply B+ between terminals 1 (1C) and 22 (1B). Continuity
      HEAD 1 (1C) - 9(1A) Apply B+ between terminals 1 (1C) and 22 (1B). Continuity
      HEAD HI 1 (1C) - 10(1B) Always Continuity
      HEAD HI 1 (1C) - 12(1A) Apply B+ between terminals 1 (1C) and 10 (1B). Continuity
      HEAD HI 1 (1C) - 1 (1B) Apply B+ between terminals 1 (1C) and 10 (1B). Continuity
      HEAD HI 1 (1C) - 8(1A) Apply B+ between terminals 1 (1C) and 10 (1B). Continuity
      HORN 1 (1Q-21 (1B) Always Continuity
      HORN 1 (1C) - 4(1A) Apply B+ between terminals 1 (1C) and 21 (1B). Continuity
      HORN 1 (1C) - 15(1A) Apply B+ between terminals 1 (1C) and 21 (1B). Continuity

      If the circuit is not as specified, replace it with relay block assembly.

      HINT:

      The relay is built in the engine room junction block. Also the relay is constructed with a relay block that is in the junction block as a unit. To disconnect the wire harness connecting with relay block is impossible. If the relay has a malfunction, replace it with the relay block assembly wire harness together.

  2. INSPECT COWL SIDE JUNCTION BLOCK LH CIRCUIT 
    Fig 5: Identifying Cowl Side Junction Block LH Circuit (1 Of 2)
    G03485743Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 6: Identifying Cowl Side Junction Block LH Circuit (2 Of 2)
    G03485744Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the fuse from the junction block and inspect the connector on the junction block side.
      FUSE SPECIFIED CONDITION

      Fuse Tester connection Condition Specified condition
      AHC-IG 2 - Ground Ignition switch ON Battery positive voltage
      POWER HTR 4 - Ground Ignition switch ON Battery positive voltage
      FUEL HTR 6 - Ground Ignition switch ON Battery positive voltage
      AHC-B, 8 - Ground Always Battery positive voltage
      DEFOG 10 - Ground Always Battery positive voltage
      AM1 12 - Ground Always Battery positive voltage
      ACC 13 - Ground Ignition switch ACC Battery positive voltage
      CIG 15 - Ground Ignition switch ACC Battery positive voltage
      PWR OUTLET 17 - Ground Ignition switch ACC Battery positive voltage
      OBD-2 20 - Ground Always Battery positive voltage
      STOP 22 - Ground Always Battery positive voltage
      A/C 24 - Ground Ignition switch ON Battery positive voltage
      TT CHARGE 26 - Ground Always Battery positive voltage
      DBL LOCK 39 - Ground Always Battery positive voltage
      ECU-B1 29 - Ground Always Battery positive voltage
      ECU-IG1 32 - Ground Ignition switch ON Battery positive voltage
      GAUGE1 34 - Ground Ignition switch ON Battery positive voltage
      EFI or ECD NO.2 35 - Ground Always Battery positive voltage
      RR WIPER 37 - Ground Ignition switch ON Battery positive voltage
      SUN ROOF 39 - Ground Always Battery positive voltage
      DOOR 41 - Ground Always Battery positive voltage
      LH SEAT 43 - Ground Always Battery positive voltage
      IDLE UP 46 - Ground Rear defogger system ON Battery positive voltage

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

    2. Remove the relay from the junction block and inspect the connector on the junction block side.
      FUSE SPECIFIED CONDITION

      Relay Tester connection Condition Specified condition
      DOME 1 - Ground Always Battery positive voltage
      DOME 5 - Ground Always Battery positive voltage
      ACC 5 - Ground Always Battery positive voltage
      CC 2 - Ground Ignition switch ON Battery positive voltage
      1 NO.2 5 - Ground Always Battery positive voltage
      IG1 NO.2 2 - Ground Ignition switch ON Battery positive voltage
      DEFOG 5 - Ground Always Battery positive voltage
      DEFOG 1 - Ground Ignition switch ON Battery positive voltage

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

  3. INSPECT COWL SIDE JUNCTION BLOCK RH CIRCUIT 
    Fig 7: Identifying Cowl SIDE Junction Block RH Circuit (1 Of 2)
    G03485745Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 8: Identifying Cowl SIDE Junction Block RH Circuit (2 Of 2)
    G03485746Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the fuse from the junction block and inspect the connector on the junction block side.
      FUSE SPECIFIED CONDITION

      Fuse Tester connection Condition Specified condition
      P/W (RL) 2 - Ground Always Battery positive voltage
      (FL) 4 - Ground Always Battery positive voltage
      RS 2 - Ground Always Battery positive voltage
      DOME 5 - Ground Always Battery positive voltage
      RADIO 7 - Ground Always Battery positive voltage
      WASHER 10 - Ground Ignition switch ON Battery positive voltage
      DIFF 12 - Ground Ignition switch ON Battery positive voltage
      ECU-B2 13 - Ground Always Battery positive voltage
      P/W(FR) 15 - Ground Always Battery positive voltage
      P/W(RR) 17 - Ground Always Battery positive voltage
      SECURITY 20 - Ground Always Battery positive voltage
      IGN 21 - Ground Ignition switch ON Battery positive voltage
      MET 23 - Ground Ignition switch ON Battery positive voltage
      GAUGE2 25 - Ground Ignition switch ON Battery positive voltage
      SEAT HTR 27 - Ground Ignition switch ON Battery positive voltage
      ECU-IG2 29 - Ground Ignition switch ON Battery positive voltage
      WIPER 31 - Ground Ignition switch ON Battery positive voltage
      RH SEAT 33 - Ground Always Battery positive voltage
      RR A/C 35 - Ground Always Battery positive voltage
      TIL &TEL 37 - Ground Always Battery positive voltage

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

      Remove the relay from the junction block and inspect the connector on the junction block side.

      FUSE SPECIFIED CONDITION

      Relay Tester connection Condition Specified condition
      ACC CUT 2 - Ground Always Battery positive voltage
      ACC CUT 4 - Ground Ignition Switch ACC Battery positive voltage
      IG1 NO.3 5 - Ground Always Battery positive voltage
      IG1 NO.3 2 - Ground Ignition Switch ON Battery positive voltage

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

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