2003 Toyota PriusFACTORY OEM SERVICE PROCEDURE

On-Vehicle Inspection

  1. INSPECT INVERTER 
    1. Turn the IG switch OFF and disconnect the 4 connectors.
    2. Apply vehicle battery's positive voltage to connector B terminal 5 (IGCT) through the fuse and apply negative voltage to connector B terminal 6 (GND).
      NOTE: Make sure to use vehicle battery (12 V). 
    3. Measure the voltage and resistance between each terminal shown below in Fig 1 and ground.
      Fig 1: Measuring Voltage & Resistance Between Terminals
      G03430969Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TERMINALS SPECIFICATIONS

      Terminal Measuring Condition Specification
      A, 5 (G - INVT)
      D, 5 (M-INVT)      		 - Approx. 2 - 4.5 V
      C, 5 (VB) - Approx. 0.5 - 4 V
      A, 4 (G - SDOWN)
      D, 4 (M - SDOWN)      		 Apply battery positive voltage to terminal through the resistance of 1 kΩ. Approx. 5 - 6 V
      B, 8 (G - FINV)
      C, 8 (M - FINV)
      B, 7 (G - SINV)
      C, 7 (M - SINV)      		 Connect the terminal to connector B terminal 6 through the resistance of 10 kΩ. 7 - 12 V after approx. 0.2 sec.
      A, 1 (G - UU)
      A, 2 (G - VU)
      A, 3 (G - WU)
      D, 1 (M - UU)
      D, 2 (M - VU)
      D, 3 (M - WU)      		 Connect the terminal to connector B terminal 6 through the resistance of 1 kΩ. Approx. 6 - 8 V
      B, 1 (G - IVA)
      B, 2 (G - IWA)
      B, 3 (G - IVB)
      B, 4 (G - IWB)
      C, 1 (M - IVA)
      C, 2 (M - IWA)
      C, 3 (M - IVB)
      C, 4 (M - IWB)      		 - Approx. 0 V
      B, 6 (GND)
      A, 6 (G - GINV)
      D, 6 (M - GINV)      		 - Continuity
      C, 6 (CVRSW) Install a cover for the connecting part of the power cable for the MG1 and MG2. Continuity
  2. INSPECT CONVERTER 
    1. Function check

      Measure the voltage of an auxiliary battery terminal when the "READY" lamp is OFF and ON.

      READY lamp is OFF:  Approx. 12 V

      READY lamp is ON:  Approx. 14 V

      Fig 2: Measuring Voltage Of Auxiliary Battery Terminal
      G03430970Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Output current check
      1. Disconnect the MG2 power cable from the inverter (See REMOVAL ).
      2. Install AC/DC 400 A probe to the wire harness of the IP connector of the converter.
      3. Connect the MG2 power cable to the inverter (See INSTALLATION ).
      4. With the READY lamp ON, operate electric devices one by one and measure the output current.

      Standard:  100 A or less

      HINT:

      If more than 100 A is shown momentarily, check for the followings.

      • Ground short of electric device.
      • Overload caused by installation of excessive device.
      • PTC heater operation.
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