DTC    P3105    Battery Smart Unit Communication Circuit Malfunction

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DESCRIPTION

The battery smart unit detects the HV battery conditions (voltage, current, and temperature) and the battery cooling fan voltage, and sends the detected signals to the HV control ECU via the serial communication system.

DTC No.
DTC Detection Condition
Trouble Area
P3105
Problem in serial communication between the battery smart unit and HV control ECU (1 trip)
Wire harness or connector
HV control ECU
Battery smart unit

MONITOR DESCRIPTION

If a malfunction in communication line between the battery smart unit and HV control ECU is detected, the HV control ECU illuminates the MIL and sets a DTC.

WIRING DIAGRAM


A109775E01


INSPECTION PROCEDURE

CAUTION:
  1. If the battery cover is removed, install it before turning the ignition switch to the ON position (or putting the vehicle into the READY-on state). If the ignition switch is turned to the ON position (or the vehicle is put into the READY-on state) with the battery cover removed, P3105 may be output.
  2. Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from reconnecting it while you are working on the high-voltage system.
  3. After disconnecting the service plug grip, wait for at least 5 minutes before touching any of the high-voltage connectors or terminals.

HINT:
At least 5 minutes is required to discharge the high-voltage capacitor inside the w/ converter inverter assembly.

1.INSPECT HYBRID VEHICLE CONTROL ECU

HINT:
By using the oscilloscope function in the intelligent tester, inspection of the function between the HV control ECU and battery smart unit can be conducted.



    A109873E02

  1. Connect the intelligent tester to the HV control ECU terminals specified in the table below, set the tester to the oscilloscope function, and check the waveform.
    Item
    		Contents
    Terminal
    		CH1: BTH+ (H30-19) - E1 (H32-5)
    CH2: BTH- (H30-30) - E1 (H32-5)
    Equipment Setting
    		2V/DIV, 500μs/DIV
    Condition
    		Ignition switch ON

    Standard:
    The waveform in the illustration can be measured.

    HINT:
    The waveform shown in the illustration varies depending on the contents of the communication.



YES
REPLACE HYBRID VEHICLE CONTROL ECU
NO


2.CHECK HARNESS AND CONNECTOR (HV CONTROL ECU - BATTERY PACK WIRE)

  1. Disconnect the H30 connector from the HV control ECU.



    A108238

  1. Disconnect the BL1 connector shown in the illustration.



    A109874E02

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance (Check for open):
    Tester Connection
    		Specified Condition
    BTH+ (H30-19) - BTH+ (BL1-5)
    		Below 1 Ω
    BTH- (H30-30) - BTH- (BL1-10)
    		Below 1 Ω

    Standard Resistance (Check for short):
    Tester Connection
    		Specified Condition
    BTH+ (H30-19) - Body ground
    		10 kΩ or higher
    BTH- (H30-30) - Body ground
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK HARNESS AND CONNECTOR (BATTERY PACK WIRE)

  1. Connect the H30 connector to the HV control ECU.



    A109797E02

  1. Measure the voltage according to the value(s) in the table below when the ignition switch is in the ON position.

    Standard Voltage:
    Tester Connection
    		Specified Condition (V)
    IGCT (BL1-1) - GND (BL1-6)
    		9 to 14 V



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


4.INSPECT BATTERY PACK WIRE

CAUTION:
Be sure to wear insulated gloves and protective goggles.

  1. Remove the service plug grip. (Click here)

  1. Remove the battery cover. (Click here)

  1. Disconnect the B26 connector from the battery smart unit.



    A109875E02

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance (Check for open):
    Tester Connection
    		Specified Condition
    BTH+ (B26-7) - BTH+ (BL1-5)
    		Below 1 Ω
    BTH- (B26-14) - BTH- (BL1-10)
    		Below 1 Ω
    IGCT (B26-1) - IGCT (BL1-1)
    		Below 1 Ω
    GND (B26-8) - GND (BL1-6)
    		Below 1 Ω

    Standard Resistance (Check for short):
    Tester Connection
    		Specified Condition
    BTH+ (B26-7) - Body ground
    		10 kΩ or higher
    BTH- (B26-14) - Body ground
    		10 kΩ or higher
    IGCT (B26-1) - Body ground
    		10 kΩ or higher
    GND (B26-8) - Body ground
    		10 kΩ or higher



NG
REPLACE BATTERY PACK WIRE
OK

REPLACE BATTERY SMART UNIT