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Home >> Toyota >> 2012 >> Prius Plug-in >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Plug-In Charge Control System (Plug-In) (Diagnostic Codes (P0560-117 - U-0293-449) & Circuit Tests) >> Plug-In Charge Control System >> DTC P0D20-422: Charger Relay Stuck Open >> Procedure
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DTC P0D20-422: Charger Relay Stuck Open: Procedure

  1. CHECK DTC OUTPUT (PLUG-IN CONTROL) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Enter the following menus: Powertrain / Plug-in Control / Trouble Codes.
    4. Check if DTCs are output.

      Result

      Result Proceed to
      Only P0D20-422 is output or P0D20-422 and DTCs other than the ones in the table below are also output. A
      Any of the following DTCs are also output. B
      DTC No. Relevant Diagnosis
      P0D4D-405 On-Board Charger Output Voltage Sensor Circuit Range / Performance
      P0D4E-416 On-Board Charger Output Voltage Sensor Circuit Low
      P0D4F-417 On-Board Charger Output Voltage Sensor Circuit High

      HINT: 

      P0D20-422 may be output due to a malfunction which causes the DTCs in the table above to be output. In this case, first troubleshoot the output DTCs in the table above. Then, perform a reproduction test to check that no DTCs are output.

    5. Turn the power switch off.

    B → See step   14 

    A: Go to next step 

  2. CHECK FREEZE FRAME DATA (CHRB STATUS, CHRB CONTROL STATUS) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Enter the following menus: Powertrain / Plug-in Control / Trouble Codes.
    4. Read the freeze frame data of DTC P0D20-422.
    5. Compare "CHRB Status" with "CHRB Control Status".

      Result

      Result Proceed to
      CHRB Status CHRB Control Status
      ON ON A
      ON OFF B
      OFF ON
    6. Turn the power switch off.

    B → See step   15 

    A: Go to next step 

  3. CHECK FREEZE FRAME DATA (CHRG STATUS, CHRG CONTROL STATUS) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Enter the following menus: Powertrain / Plug-in Control / Trouble Codes.
    4. Read the freeze frame data of DTC P0D20-422.
    5. Compare "CHRG Status" with "CHRG Control Status".

      Result

      Result Proceed to
      CHRG Status CHRG Control Status
      ON ON A
      ON OFF B
      OFF ON
    6. Turn the power switch off.

    B → See step   15 

    A: Go to next step 

  4. CHECK ELECTRIC VEHICLE CHARGER WIRE 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair information because this may cause a malfunction.

    2. Disconnect the a2 electric vehicle charger assembly connector. Refer to REMOVAL - Step 14 .
      Fig 1: Identifying a2 Connector
      GTY335247Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Remove the No. 2 hybrid vehicle battery shield panel. Refer to REMOVAL - Step 28 .
    4. Disconnect the a3 hybrid battery junction block assembly connector.
      Fig 2: Identifying a3 Hybrid Battery Junction Block Assembly Connector
      GTY326191Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Measure the resistance according to the value(s) in the table below.
      Fig 3: Checking a2 & a3 Connector Terminals
      GTY343698Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      a2-1 (DCHB) - a2-2 (DCHG) Power switch off 10 kΩ or higher
      a2-1 (DCHB) - a3- 6 (DCHB) Power switch off Below 1 Ω
      a2-2 (DCHG) - a3- 3 (DCHG) Power switch off Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Electric Vehicle Charger Wire
      (Electric Vehicle Charger Assembly Side)
      *b Electric Vehicle Charger Wire
      (Hybrid Battery Junction Block Assembly Side)
    6. Connect the hybrid battery junction block assembly connector.
    7. Install the No. 2 hybrid vehicle battery shield panel.
    8. Connect the electric vehicle charger assembly connector.

    NG → See step   10 

    OK: Go to next step 

  5. CHECK HYBRID BATTERY JUNCTION BLOCK ASSEMBLY 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair information because this may cause a malfunction.

    2. Remove the No. 2 hybrid vehicle battery shield panel. Refer to REMOVAL - Step 28 .
    3. Disconnect the a3 hybrid battery junction block assembly connector.
      Fig 4: Identifying a3 Hybrid Battery Junction Block Assembly Connector
      GTY326191Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Measure the resistance according to the value(s) in the table below.
      Fig 5: Checking a3 Connector Terminals
      GTY339558Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      a3-3 (DCHG) - a3-6 (DCHB) Power switch off 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Hybrid Battery Junction Block Assembly
    5. Connect the hybrid battery junction block assembly connector.
    6. Install the No. 2 hybrid vehicle battery shield panel.

    NG → See step   11 

    OK: Go to next step 

  6. CHECK HYBRID BATTERY JUNCTION BLOCK ASSEMBLY (CHRB, CHRG) 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair information because this may cause a malfunction.

    2. Remove the No. 1 hybrid vehicle battery shield panel. Refer to REMOVAL - Step 29 .
    3. Disconnect the T14 and T15 hybrid battery junction block assembly terminals.
      Fig 6: Identifying T14 & T15 Terminals
      GTY332034Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Disconnect the a3 hybrid battery junction block assembly connector.
      Fig 7: Identifying a3 Hybrid Battery Junction Block Assembly Connector
      GTY326191Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Disconnect the w2 and q8 hybrid battery junction block assembly connectors.
      Fig 8: Identifying Connectors
      GTY332276Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Disconnect the co1 battery pack wire connector.
      Fig 9: Identifying co1 Connector
      GTY328472Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. Measure the resistance according to the value(s) in the table below.
      Fig 10: Inspecting Hybrid Battery Junction Block Assembly
      GTY325870Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      T15-1 (CBI) - a3-6 (DCHB) Auxiliary battery voltage is applied between terminals co1-4 (CHRB) - co1-5 (GND) Below 1 Ω
      T14-1 (CEI) - a3-3 (DCHG) Auxiliary battery voltage is applied between terminals co1-6 (CHRG) - co1-5 (GND) Below 1 Ω
      TEXT IN ILLUSTRATION

      *1 Hybrid Battery Junction Block Assembly
    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      co1-4 (CHRB) - co1-5 (GND) -40 to 80 °C (-40 to 176°F) 112 to 274 Ω
      co1-6 (CHRG) - co1-5 (GND) -40 to 80 °C (-40 to 176°F) 112 to 274 Ω
    9. Connect the battery pack wire connector.
    10. Connect the hybrid battery junction block assembly connector.
    11. Install the No. 1 hybrid vehicle battery shield panel.

    NG → See step   13 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (PLUGIN CHARGE CONTROL ECU ASSEMBLY - BATTERY PACK WIRE CONNECTOR) 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair information because this may cause a malfunction.

    2. Disconnect connector S31 from the plugin charge control ECU assembly.
    3. Remove the No. 2 hybrid vehicle battery shield panel. Refer to REMOVAL - Step 28 .
    4. Disconnect the co1 battery pack wire connector.
      Fig 11: Identifying co1 Connector
      GTY328472Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Measure the resistance according to the value(s) in the table below.
      Fig 12: Checking S31 & co1 Connector Terminals
      GTY332122Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      S31-4 (CHRB) - co1-4 (CHRB) Power switch off Below 1 Ω
      S31-15 (CHRG) - co1-6 (CHRG) Power switch off Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Plugin Charge Control ECU Assembly)
      *b Front view of wire harness connector
      (to Battery Pack Wire Connector)
    6. Connect the battery pack wire connector.
    7. Install the No. 2 hybrid vehicle battery shield panel.
    8. Connect the plugin charge control ECU assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. CHECK ELECTRIC VEHICLE FUSE 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair information because this may cause a malfunction.

    2. Remove the No. 1 hybrid vehicle battery shield panel. Refer to REMOVAL - Step 29 .
    3. Measure the resistance according to the value(s) in the table below.
      Fig 13: Identifying Electric Vehicle Fuse Terminals
      GTY330253Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      Electric vehicle fuse Power switch off Below 1 Ω
    4. Install the No. 1 hybrid vehicle battery shield panel.

    NG → See step   9 

    OK → See step   18 

  9. REPLACE ELECTRIC VEHICLE FUSE 

    Refer to COMPONENTS

    NEXT → See step   18 

  10. REPLACE ELECTRIC VEHICLE CHARGER WIRE 

    Refer to COMPONENTS

    NEXT → See step   12 

  11. REPLACE HYBRID BATTERY JUNCTION BLOCK ASSEMBLY 

    Refer to COMPONENTS

    NEXT: Go to next step 

  12. CHECK ELECTRIC VEHICLE FUSE 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair information because this may cause a malfunction.

    2. Remove the No. 1 hybrid vehicle battery shield panel. Refer to REMOVAL - Step 29 .
    3. Measure the resistance according to the value(s) in the table below.
      Fig 14: Identifying Electric Vehicle Fuse Terminals
      GTY330253Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      Electric vehicle fuse Power switch off Below 1 Ω
    4. Install the No. 1 hybrid vehicle battery shield panel.

    NG → See step   17 

    OK → END 

  13. CHECK HARNESS AND CONNECTOR (BATTERY PACK WIRE CONNECTOR - HYBRID BATTERY JUNCTION BLOCK ASSEMBLY) 
    WARNING:

    Be sure to wear insulated gloves and protective goggles.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair information because this may cause a malfunction.

    2. Remove the upper hybrid battery cover sub-assembly. Refer to REMOVAL - Step 32 .
    3. Disconnect the co1 battery pack wire connector.
      Fig 15: Identifying co1 Connector
      GTY328472Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Disconnect connector o9 from the hybrid battery junction block assembly.
      Fig 16: Identifying o9 Connector
      GTY325146Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Measure the resistance according to the value(s) in the table below.
      Fig 17: Checking co1 & o9 Connector Terminals
      GTY325455Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      co1-4 (CHRB) - o9-5 (CHRB) Power switch off Below 1 Ω
      co1-6 (CHRG) - o9-3 (CHRG) Power switch off Below 1 Ω
      co1-5 (GND) - o9-4 (GND) Power switch off Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Battery Pack Wire Connector)
      *b Front view of wire harness connector
      (to Hybrid Battery Junction Block Assembly)
    6. Connect the hybrid battery junction block assembly connector.
    7. Connect the battery pack wire connector.
    8. Install the upper hybrid battery cover sub-assembly.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   16 

  14. GO TO DTC CHART (PLUG-IN CHARGE CONTROL SYSTEM). Refer to  DIAGNOSTIC TROUBLE CODE CHART 
  15. REPLACE PLUGIN CHARGE CONTROL ECU ASSEMBLY. Refer to  COMPONENTS 
  16. REPLACE HYBRID BATTERY JUNCTION BLOCK ASSEMBLY. Refer to  COMPONENTS 
  17. REPLACE ELECTRIC VEHICLE FUSE. Refer to  COMPONENTS 
  18. REPLACE ELECTRIC VEHICLE CHARGER ASSEMBLY. Refer to  COMPONENTS 
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