U029A

P310 HYBRID BATTERY CONTROL: HYBRID BATTERY SYSTEM: U029A: Lost Communication with Hybrid Battery Pack Sensor Module

DTC U029A - Lost Communication with Hybrid Battery Pack Sensor Module

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.






MONITOR DESCRIPTION

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

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





COMPONENT OPERATING RANGE





WIRING DIAGRAM





INSPECTION PROCEDURE
CAUTION:
- 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, U029A may be output.
- Before inspecting the high-voltage system, 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 5 minutes before touching any of the high-voltage connectors or terminals. After waiting for 5 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.
HINT: Waiting for at least 5 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

PROCEDURE

1. INSPECT HV CONTROL ECU
HINT: By using the oscilloscope function in Techstream, inspection of the function between the HV control ECU and battery smart unit can be conducted.





(a) Connect Techstream to the HV control ECU terminals specified in the table below, set the tester to the oscilloscope function, and check the waveform.






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 HV CONTROL ECU
NO -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (HV CONTROL ECU - BATTERY PACK WIRE)
(a) Disconnect the H30 connector from the HV control ECU.





(b) Disconnect the BP1 connector shown in the illustration.





(c) Measure the resistance according to the value(s) in the table below.
Standard resistance (Check for open):






Standard resistance (Check for short):






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (BATTERY PACK WIRE)
(a) Connect the H30 connector to the HV control ECU.





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






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. INSPECT BATTERY PACK WIRE
CAUTION: Be sure to wear insulated gloves and protective goggles.
(a) Remove the service plug grip. Hybrid Battery System

(b) Remove the battery cover. Components

(c) Disconnect the B28 connector from the battery smart unit.





(d) Measure the resistance according to the value(s) in the table below.
Standard resistance (Check for open):






Standard resistance (Check for short):






NG -- REPLACE BATTERY PACK WIRE
OK -- REPLACE BATTERY SMART UNIT