LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2020 >> ES 300h Luxury >> Repair and Diagnosis >> External Pages >> Different car >> Section 201 (Hybrid Battery System (For Lithium-Ion Battery) - Diagnostic Codes (3 Of 3) & Circuit Tests) >> HYBRID BATTERY SYSTEM (for LITHIUM-ION BATTERY) >> DTC P1AC4-9E: Hybrid/EV Battery Stack 1 Current Interrupt Device Stuck On; DTC P1AC5-9E: Hybrid/EV Battery Stack 2 Current Interrupt Device Stuck On [08/2020 - ] >> Procedure

DTC P1AC4-9E: Hybrid/EV Battery Stack 1 Current Interrupt Device Stuck On; DTC P1AC5-9E: Hybrid/EV Battery Stack 2 Current Interrupt Device Stuck On [08/2020 - ]: Procedure

WARNING: This page is about a different car, the 2024 Lexus ES 300h, 2023 Lexus ES 300h, 2022 Lexus ES 300h, and 2021 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK DTC OUTPUT (HV BATTERY, HYBRID CONTROL) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Enter the following menus: Powertrain / HV Battery and Hybrid Control / Trouble Codes.
    4. Check for DTCs.

      Powertrain > HV Battery > Trouble Codes 

      Powertrain > Hybrid Control > Trouble Codes 

      Result

      Result Proceed to
      "P1AC4-9E or P1AC5-9E" only is output, or DTCs except the ones in the table below are also output. A
      DTCs of hybrid battery system in the table below are output. B
      DTCs of hybrid control system in the table below are output. C
      System Relevant DTC
      Hybrid battery system P060A-47 Hybrid/EV Battery Energy Control Module Monitoring Processor Watchdog / Safety MCU Failure
      P060B-49 Hybrid/EV Battery Energy Control Module A/D Processing Internal Electronic Failure
      P0606-87 Hybrid/EV Battery Energy Control Module Processor to Monitoring Processor Missing Message
      Hybrid control system P0A1F-94 Hybrid/EV Battery Energy Control Module Unexpected Operation
    5. Turn the power switch off.

    Result: 

    GO TO DTC CHART (HYBRID BATTERY SYSTEM). Refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2020 - ] 

    Result: 

    GO TO DTC CHART (HYBRID CONTROL SYSTEM). Refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2020 - 08/2021]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2021 - ] 

    Result: 

    See step  2

  2. CHECK DTC 
    1. Check the DTCs that were output when the vehicle was brought to the workshop.

      Result

      Result Proceed to
      "P1AC4-9E" is also output. A
      "P1AC5-9E" is also output. B

    Result: 

    See step  6

    Result: 

    See step  3

  3. CHECK CONNECTOR CONNECTION CONDITION (BATTERY ECU ASSEMBLY CONNECTOR) 
    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 appropriate service information because this may cause a malfunction.

    2. Remove the No. 1 HV battery hose.

      Refer to PROCEDURE - Step 21 [08/2020 - 08/2021] , or refer to PROCEDURE - Step 21 [08/2021 - 09/2022] , or refer to PROCEDURE - Step 21 [09/2022 - ]

    3. Check the connector connections and contact pressure of the relevant terminals for the battery ECU assembly.

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [06/2018 - ]

      OK

      The connector is connected securely and there are no contact problems.

      Result

      Result Proceed to
      OK A
      Not connected securely The terminals are not damaged or corroded B
      Not connected securely The terminals are damaged or corroded C
      GTY946901Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Install the No. 1 HV battery hose.

    Result: 

    CONNECT SECURELY 

    Result: 

    REPLACE NO. 1 HV SUPPLY STACK SUB-ASSEMBLY. Refer to  REMOVAL [08/2020 - 08/2021]  , or refer to  REMOVAL [08/2021 - 09/2022]  , or refer to  REMOVAL [09/2022 - ] 

    Result: 

    See step  4

  4. CHECK BATTERY ECU ASSEMBLY (GA0 - VA35) 
    NOTE:

    Make sure to use tester probes with a diameter of approximately 0.5 mm (0.0197 in.) when measuring the voltage.

    1. Remove the battery ECU assembly.

      Refer to REMOVAL [08/2020 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

    2. Measure the voltage according to the value(s) in the table below.
      GTY946945Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Battery ECU Assembly)
      - -

      Standard Voltage

      HV Battery Cell Tester Connection
      (Tester Probe Polarity)
      Condition Specified Condition
      1 y15-1 (GA0) (+) - y15-13 (VA1) (-) Always 0.3 to 1.0 V
      2 y15-13 (VA1) (+) - y15-25 (VA2) (-) Always 0.3 to 1.0 V
      3 y15-25 (VA2) (+) - y15-2 (VA3) (-) Always 0.3 to 1.0 V
      4 y15-2 (VA3) (+) - y15-14 (VA4) (-) Always 0.3 to 1.0 V
      5 y15-14 (VA4) (+) - y15-26 (VA5) (-) Always 0.3 to 1.0 V
      6 y15-26 (VA5) (+) - y15-3 (VA6) (-) Always 0.3 to 1.0 V
      7 y15-3 (VA6) (+) - y15-15 (VA7) (-) Always 0.3 to 1.0 V
      8 y15-15 (VA7) (+) - y15-27 (VA8) (-) Always 0.3 to 1.0 V
      9 y15-27 (VA8) (+) - y15-4 (VA9) (-) Always 0.3 to 1.0 V
      10 y15-4 (VA9) (+) - y15-16 (VA10) (-) Always 0.3 to 1.0 V
      11 y15-16 (VA10) (+) - y15-28 (VA11) (-) Always 0.3 to 1.0 V
      12 y15-28 (VA11) (+) - y15-5 (VA12) (-) Always 0.3 to 1.0 V
      13 y15-5 (VA12) (+) - y15-17 (VA13) (-) Always 0.3 to 1.0 V
      14 y15-17 (VA13) (+) - y15-29 (VA14) (-) Always 0.3 to 1.0 V
      15 y15-29 (VA14) (+) - y15-6 (VA15) (-) Always 0.3 to 1.0 V
      16 y15-6 (VA15) (+) - y15-18 (VA16) (-) Always 0.3 to 1.0 V
      17 y15-18 (VA16) (+) - y15-30 (VA17) (-) Always 0.3 to 1.0 V
      18 y15-30 (VA17) (+) - y15-7 (VA18) (-) Always 0.3 to 1.0 V
      19 y15-7 (VA18) (+) - y15-19 (VA19) (-) Always 0.3 to 1.0 V
      20 y15-19 (VA19) (+) - y15-31 (VA20) (-) Always 0.3 to 1.0 V
      21 y15-31 (VA20) (+) - y15-8 (VA21) (-) Always 0.3 to 1.0 V
      22 y15-8 (VA21) (+) - y15-20 (VA22) (-) Always 0.3 to 1.0 V
      23 y15-20 (VA22) (+) - y15-32 (VA23) (-) Always 0.3 to 1.0 V
      24 y15-32 (VA23) (+) - y15-9 (VA24) (-) Always 0.3 to 1.0 V
      25 y15-9 (VA24) (+) - y15-21 (VA25) (-) Always 0.3 to 1.0 V
      26 y15-21 (VA25) (+) - y15-33 (VA26) (-) Always 0.3 to 1.0 V
      27 y15-33 (VA26) (+) - y15-10 (VA27) (-) Always 0.3 to 1.0 V
      28 y15-10 (VA27) (+) - y15-22 (VA28) (-) Always 0.3 to 1.0 V
      29 y15-22 (VA28) (+) - y15-34 (VA29) (-) Always 0.3 to 1.0 V
      30 y15-34 (VA29) (+) - y15-11 (VA30) (-) Always 0.3 to 1.0 V
      31 y15-11 (VA30) (+) - y15-23 (VA31) (-) Always 0.3 to 1.0 V
      32 y15-23 (VA31) (+) - y15-35 (VA32) (-) Always 0.3 to 1.0 V
      33 y15-35 (VA32) (+) - y15-12 (VA33) (-) Always 0.3 to 1.0 V
      34 y15-12 (VA33) (+) - y15-24 (VA34) (-) Always 0.3 to 1.0 V
      35 y15-24 (VA34) (+) - y15-36 (VA35) (-) Always 0.3 to 1.0 V
      NOTE:
      • Make sure to check the polarity of each terminal (positive (+) or negative (-)) before connecting a tester.
      • Be sure to set the toyota electrical tester to diode range when performing this test.
      • Read the voltage after the value has stabilized.
      • In order to avoid damaging the terminals of the battery ECU assembly, make sure to use tester probes with a diameter of approximately 0.5 mm (0.0197 in.) when measuring the voltage of the battery ECU assembly.

      Result

      Result Proceed to
      The voltage between the terminals is 0.3 to 1.0 V. A
      Other than above B
    3. Install the battery ECU assembly.

    Result: 

    REPLACE NO. 1 HV SUPPLY STACK SUB-ASSEMBLY. Refer to  REMOVAL [08/2020 - 08/2021]  , or refer to  REMOVAL [08/2021 - 09/2022]  , or refer to  REMOVAL [09/2022 - ] 

    Result: 

    See step  5

  5. REPLACE NO. 1 HV SUPPLY STACK SUB-ASSEMBLY 

    Refer to REMOVAL [08/2020 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    REPLACE BATTERY ECU ASSEMBLY. Refer to  REMOVAL [08/2020 - 08/2021]  , or refer to  REMOVAL [08/2021 - 09/2022]  , or refer to  REMOVAL [09/2022 - ] 

  6. CHECK CONNECTOR CONNECTION CONDITION (BATTERY ECU ASSEMBLY CONNECTOR) 
    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 appropriate service information because this may cause a malfunction.

    2. Remove the No. 1 HV battery hose.

      Refer to PROCEDURE - Step 21 [08/2020 - 08/2021] , or refer to PROCEDURE - Step 21 [08/2021 - 09/2022] , or refer to PROCEDURE - Step 21 [09/2022 - ]

    3. Check the connector connections and contact pressure of the relevant terminals for the battery ECU assembly.

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [06/2018 - ]

      OK

      The connector is connected securely and there are no contact problems.

      GTY946857Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result

      Result Proceed to
      OK A
      Not connected securely The terminals are not damaged or corroded B
      Not connected securely The terminals are damaged or corroded C
    4. Install the No. 1 HV battery hose.

    Result: 

    CONNECT SECURELY 

    Result: 

    REPLACE NO. 2 HV SUPPLY STACK SUB-ASSEMBLY. Refer to  REMOVAL [08/2020 - 08/2021]  , or refer to  REMOVAL [08/2021 - 09/2022]  , or refer to  REMOVAL [09/2022 - ] 

    Result: 

    See step  7

  7. CHECK BATTERY ECU ASSEMBLY (VAD - VA70) 
    NOTE:

    Make sure to use tester probes with a diameter of approximately 0.5 mm (0.0197 in.) when measuring the voltage.

    1. Remove the battery ECU assembly.

      Refer to REMOVAL [08/2020 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

    2. Measure the voltage according to the value(s) in the table below.
      GTY946988Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Battery ECU Assembly)
      - -

      Standard Voltage

      HV Battery Cell Tester Connection
      (Tester Probe Polarity)
      Condition Specified Condition
      36 y13-1 (VAD) (+) - y13-13 (VA36) (-) Always 0.3 to 1.0 V
      37 y13-13 (VA36) (+) - y13-25 (VA37) (-) Always 0.3 to 1.0 V
      38 y13-25 (VA37) (+) - y13-2 (VA38) (-) Always 0.3 to 1.0 V
      39 y13-2 (VA38) (+) - y13-14 (VA39) (-) Always 0.3 to 1.0 V
      40 y13-14 (VA39) (+) - y13-26 (VA40) (-) Always 0.3 to 1.0 V
      41 y13-26 (VA40) (+) - y13-3 (VA41) (-) Always 0.3 to 1.0 V
      42 y13-3 (VA41) (+) - y13-15 (VA42) (-) Always 0.3 to 1.0 V
      43 y13-15 (VA42) (+) - y13-27 (VA43) (-) Always 0.3 to 1.0 V
      44 y13-27 (VA43) (+) - y13-4 (VA44) (-) Always 0.3 to 1.0 V
      45 y13-4 (VA44) (+) - y13-16 (VA45) (-) Always 0.3 to 1.0 V
      46 y13-16 (VA45) (+) - y13-28 (VA46) (-) Always 0.3 to 1.0 V
      47 y13-28 (VA46) (+) - y13-5 (VA47) (-) Always 0.3 to 1.0 V
      48 y13-5 (VA47) (+) - y13-17 (VA48) (-) Always 0.3 to 1.0 V
      49 y13-17 (VA48) (+) - y13-29 (VA49) (-) Always 0.3 to 1.0 V
      50 y13-29 (VA49) (+) - y13-6 (VA50) (-) Always 0.3 to 1.0 V
      51 y13-6 (VA50) (+) - y13-18 (VA51) (-) Always 0.3 to 1.0 V
      52 y13-18 (VA51) (+) - y13-30 (VA52) (-) Always 0.3 to 1.0 V
      53 y13-30 (VA52) (+) - y13-7 (VA53) (-) Always 0.3 to 1.0 V
      54 y13-7 (VA53) (+) - y13-19 (VA54) (-) Always 0.3 to 1.0 V
      55 y13-19 (VA54) (+) - y13-31 (VA55) (-) Always 0.3 to 1.0 V
      56 y13-31 (VA55) (+) - y13-8 (VA56) (-) Always 0.3 to 1.0 V
      57 y13-8 (VA56) (+) - y13-20 (VA57) (-) Always 0.3 to 1.0 V
      58 y13-20 (VA57) (+) - y13-32 (VA58) (-) Always 0.3 to 1.0 V
      59 y13-32 (VA58) (+) - y13-9 (VA59) (-) Always 0.3 to 1.0 V
      60 y13-9 (VA59) (+) - y13-21 (VA60) (-) Always 0.3 to 1.0 V
      61 y13-21 (VA60) (+) - y13-33 (VA61) (-) Always 0.3 to 1.0 V
      62 y13-33 (VA61) (+) - y13-10 (VA62) (-) Always 0.3 to 1.0 V
      63 y13-10 (VA62) (+) - y13-22 (VA63) (-) Always 0.3 to 1.0 V
      64 y13-22 (VA63) (+) - y13-34 (VA64) (-) Always 0.3 to 1.0 V
      65 y13-34 (VA64) (+) - y13-11 (VA65) (-) Always 0.3 to 1.0 V
      66 y13-11 (VA65) (+) - y13-23 (VA66) (-) Always 0.3 to 1.0 V
      67 y13-23 (VA66) (+) - y13-35 (VA67) (-) Always 0.3 to 1.0 V
      68 y13-35 (VA67) (+) - y13-12 (VA68) (-) Always 0.3 to 1.0 V
      69 y13-12 (VA68) (+) - y13-24 (VA69) (-) Always 0.3 to 1.0 V
      70 y13-24 (VA69) (+) - y13-36 (VA70) (-) Always 0.3 to 1.0 V
      NOTE:
      • Make sure to check the polarity of each terminal (positive (+) or negative (-)) before connecting a tester.
      • Be sure to set the toyota electrical tester to diode range when performing this test.
      • Read the voltage after the value has stabilized.
      • In order to avoid damaging the terminals of the battery ECU assembly, make sure to use tester probes with a diameter of approximately 0.5 mm (0.0197 in.) when measuring the voltage of the battery ECU assembly.

      Result

      Result Proceed to
      The voltage between the terminals is 0.3 to 1.0 V. A
      Other than above B
    3. Install the battery ECU assembly.

    Result: 

    REPLACE NO. 2 HV SUPPLY STACK SUB-ASSEMBLY. Refer to  REMOVAL [08/2020 - 08/2021]  , or refer to  REMOVAL [08/2021 - 09/2022]  , or refer to  REMOVAL [09/2022 - ] 

    Result: 

    See step  8

  8. REPLACE NO. 2 HV SUPPLY STACK SUB-ASSEMBLY 

    Refer to REMOVAL [08/2020 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    REPLACE BATTERY ECU ASSEMBLY. Refer to  REMOVAL [08/2020 - 08/2021]  , or refer to  REMOVAL [08/2021 - 09/2022]  , or refer to  REMOVAL [09/2022 - ]