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Home >> Lexus >> 2007 >> GS 450h >> Repair and Diagnosis (Single Page) >> Hybrid/Electric Powertrain >> Testing and Diagnosis >> Vehicle Control - L110 Hybrid - DTC P2798 Through DTC U0424 >> DTC U0110-159 Lost Communication with Driver Motor Control Module; DTC U0110-656 Lost Communication with Driver Motor Control Module; DTC U0110-657 Lost Communication with Driver Motor Control Module >> Inspection Procedure
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Inspection Procedure

CAUTION:
  • Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with converter assembly, take safety precautions such as wearing insulated gloves and removing the service plug grip to prevent electrical shocks. After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
  • After disconnecting the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting, check the voltage at the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.
NOTE:
  • If any of U0110-159, 656 or 657 are detected, clearing DTCs using the intelligent tester will cause DTC P0A1B-788 (power source IC reset) to be output. Proceed to troubleshooting without considering this code.
  • After inspection, be sure to inspect the fuse for continuity. If there is no continuity, replace the fuse.

HINT:

Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

  1. CLEAR DTC (HV) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the power switch on (IG).
    3. Read and record the DTCs and freeze frame data.
    4. Select the following menu items: DIAGNOSIS / OBD / MOBD / HV ECU / DTC INFO / CLEAR CODES.
    5. Clear the DTCs.
  2. RECONFIRM DTC OUTPUT (HV) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the power switch on (IG).
    3. Select the following menu items: DIAGNOSIS / OBD / MOBD / HV ECU / DTC INFO / CURRENT CODES.
    4. Check if DTCs are output.

      Result: DTC U0110-159,160, 656 or 657 is output. 

    NO: CHECK FOR INTERMITTENT PROBLEMS 

    YES: GO TO Next Step  .

  3. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY POWER SOURCE CIRCUIT) 
    CAUTION: Be sure to wear insulated gloves.
    1. Turn the power switch off and remove the service plug grip (See HYBRID CONTROL SYSTEM ).
      NOTE: After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.
    2. Disconnect connector A60 from the inverter with converter assembly.
    3. Turn the power switch off.
    4. Measure the resistance according to the value(s) in the chart below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      GND1 (A60-11) - Body ground Below 1 Ω
      GND2 (A60-10) - Body ground Below 1 Ω
    5. Turn the power switch on (IG).
    6. Measure the voltage according to the value(s) in the chart below.
      Fig 1: Identifying Inverter With Converter Assembly Connector Terminal A60
      G05304699Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      +B (A60-31) - Body ground 10 to 14 V
      +B2 (A60-30) - Body ground 10 to 14 V
      NOTE: Turning the power switch on (IG) with the low voltage connector of the inverter with converter assembly disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    NG: REPAIR OR REPLACE POWER SOURCE CIRCUIT 

    OK: GO TO Next Step  .

  4. CHECK HARNESS AND CONNECTOR (HV CONTROL ECU - INVERTER WITH CONVERTER ASSEMBLY) 
    1. Turn the power switch off.
    2. Disconnect connector A54 from the hybrid vehicle control ECU.
    3. Turn the power switch on (IG).
    4. Measure the voltage according to the value(s) in the chart below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      CLK+ (A54-107) - Body ground Below 1 V
      CLK- (A54-84) - Body ground Below 1 V
      REQ+ (A54-108) - Body ground Below 1 V
      REQ- (A54-85) - Body ground Below 1 V
      MTH+ (A54-106) - Body ground Below 1 V
      MTH- (A54-83) - Body ground Below 1 V
      NOTE: Turning the power switch on (IG) with the low voltage connector of the inverter with converter assembly or hybrid vehicle control ECU connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.
    5. Turn the power switch off.
    6. Measure the resistance according to the value(s) in the chart below.
      Fig 2: Identifying Hybrid Vehicle Control ECU Connector Terminal A54
      G05304700Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      CLK+ (A54-107) - CLK+ (A60-39) Below 1 Ω
      CLK- (A54-84) - CLK- (A60-38) Below 1 Ω
      REQ+ (AS4-108) - REQ+ (A60-29) Below 1 Ω
      REQ- (A54-85) - REQ- (A60-20) Below 1 Ω
      MTH+ (A54-106) - MTH+ (A60-8) Below 1 Ω
      MTH- (A54-83) - MTH- (A60-7) Below 1 Ω

      Standard resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      CLK+ (A54-107) or CLK+ (A60-39) - Body ground 10 kΩ or more
      CLK- (A54-84) or CLK- (A60-38) - Body ground 10 kΩ or more
      REQ+ (A54-108) or REQ+ (A60-29) - Body ground 10 kΩ or more
      REQ- (A54-85) or REQ- (A60-20) - Body ground 10 kΩ or more
      MTH+ (A54-106) or MTH+ (A60-8) - Body ground 10 kΩ or more
      MTH- (A54-83) or MTH- (A60-7) - Body ground 10 kΩ or more

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO Next Step  .

  5. CHECK HYBRID VEHICLE CONTROL ECU 
    1. Turn the power switch off.
    2. Connect the connector to the hybrid vehicle control ECU connector.
    3. Measure the resistance according to the value(s) in the chart below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      CLK+ (A60-39) - CLK- (A60-38) 109 to 139 Ω
      REQ+ (A60-29) - REQ- (A60-20) 109 to 139 Ω
      MTH+ (A60-8) - MTH- (A60-7) 109 to 139 Ω

    NG: REPLACE HYBRID VEHICLE CONTROL ECU (See  REMOVAL  ) 

    Fig 3: Identifying Hybrid Vehicle Control ECU Connector Terminal A60
    G05304701Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO Next Step  .

  6. CHECK INVERTER WITH CONVERTER ASSEMBLY 
    1. Turn the power switch off.
    2. Connect the connector to the inverter with converter assembly.
    3. Disconnect connector A54 from the hybrid vehicle control ECU.
    4. Measure the resistance according to the value(s) in the chart below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      CLK+ (A54-107) - CLK- (A54-84) 109 to 139 Ω
      REQ+ (A54-108) - REQ- (A54-85) 109 to 139 Ω
      MTH+ (A54-106) - MTH- (A54-83) 109 to 139 Ω
      Fig 4: Identifying Hybrid Vehicle Control ECU Connector Terminal A54
      G05304702Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE INVERTER WITH CONVERTER ASSEMBLY 

    OK: GO TO Next Step  .

  7. CHECK HYBRID VEHICLE CONTROL ECU 
    1. Connect the hybrid vehicle control ECU connectors.
    2. Disconnect connector A60 from the inverter with converter assembly.
    3. Connect an oscilloscope between the inverter with convertor assembly connector terminals specified in the chart below, and measure the waveform.
      ITEM CONTENT CHART

      Item Contents
      Terminal CH1: CLK+ (A60-39) - GND1 (A60-11)
      CH2: CLK- (A60-38) - GND1 (A60-11)
      CH1: REQ+ (A60-29) - GND1 (A60-11)
      CH1: REQ- (A60-20) - GND1 (A60-11)
      CH1: HTM+ (A60-27) - GND1 (A60-11)
      CH1: HTM- (A60-26 - GND1 (A60-11)
      Equipment Setting CH1, 2:1 V/DIV., 1 μs/DIV.
      CH3, 4: 1 V/DIV., 1 ms/DIV.
      CH5, 6: 1 V/DIV., 200 μs/DIV.
      Condition Power switch on (IG)

      Result: The waveform appears as shown in the illustration. 

      NOTE: Turning the power switch on (IG) with the low voltage connector of the inverter with converter assembly disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    NG: REPLACE HYBRID VEHICLE CONTROL ECU (See  REMOVAL  ) 

    Fig 5: Identifying Inverter With Converter Assembly Connector A60
    G05304703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE INVERTER WITH CONVERTER ASSEMBLY 

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