U029A

HYBRID BATTERY CONTROL: HYBRID BATTERY SYSTEM: U029A-123: Lost Communication with Hybrid Battery Pack Sensor Module

DTC U029A-123 - 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 voltages, and sends the detected information to the hybrid vehicle control ECU via serial communication.






MONITOR DESCRIPTION

If the battery smart unit detects a malfunction in serial communication with the hybrid vehicle control ECU, it will illuminate the MIL and set a DTC.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





COMPONENT OPERATING RANGE





WIRING DIAGRAM





INSPECTION PROCEDURE
CAUTION:
- 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 10 minutes before touching any of the high-voltage connectors or terminals.
HINT: Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (VOLTAGE)
CAUTION: Be sure to wear insulated gloves.
(a) Remove the service plug grip Removal.
(b) Remove the battery smart unit Removal.
(c) Disconnect connector n2 from the battery smart unit.
(d) Turn the power switch on (IG).




(e) Measure the voltage according to the value(s) in the table below.
Standard voltage:





HINT: If the power switch is turned on (IG) with the service plug grip removed, DTC P0A0D-350 for the interlock switch system will be set.

NG -- CHECK FUSE
OK -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - BATTERY SMART UNIT)
CAUTION: Be sure to wear insulated gloves.
(a) Disconnect connector A61 from the hybrid vehicle control ECU.




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






Standard resistance (Check for short):





(c) Turn the power switch on (IG).
(d) Measure the voltage according to the value(s) in the table below.
Standard voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. CHECK WAVEFORM
CAUTION: Be sure to wear insulated gloves.
(a) Connect connector A61 to the hybrid vehicle control ECU.
(b) Connect connector n2 to the battery smart unit.




(c) Connect an oscilloscope between the battery smart unit terminals specified in the table below, and measure the waveform.






NG -- REPLACE BATTERY SMART UNIT
OK -- REPLACE HYBRID VEHICLE CONTROL ECU
4. CHECK FUSE




(a) Remove the IGCT No. 2 fuse from the engine room relay block.
(b) Measure the resistance of the IGCT No. 2 fuse.
Standard resistance:
Below 1 Ohms
NG -- REPLACE FUSE
OK -- Continue to next step.
5. CHECK HARNESS AND CONNECTOR (BATTERY SMART UNIT - ENGINE ROOM RELAY BLOCK NO. 1)
CAUTION: Be sure to wear insulated gloves.
(a) Install the IGCT No. 2 fuse to the engine room relay block.
(b) Remove the integration relay from the engine room relay block.
(c) Disconnect connector n2 from the battery smart unit.




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






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- CHECK AND REPAIR POWER SOURCE CIRCUIT