U029A
HYBRID / BATTERY CONTROL: HYBRID BATTERY SYSTEM: U029A-123: Lost Communication with Hybrid Battery Pack Sensor Module
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 voltage, and sends the detected signals to the hybrid vehicle control ECU via the serial communication system.
MONITOR DESCRIPTION
If a malfunction in communication line between the battery smart unit and hybrid vehicle control ECU is detected, the hybrid vehicle control ECU illuminates the MIL and sets a DTC.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
COMPONENT OPERATING RANGE
WIRING DIAGRAM
Refer to the wiring diagram for DTC P0A1F-123 P0A1F.
INSPECTION PROCEDURE
CAUTION:
* If the battery cover is removed, install it before turning the power switch on (IG) or (READY). If the power switch is turned on (IG) or (READY) with the battery cover removed, U029A-123 may be set.
* 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 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
At least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.
PROCEDURE
1. CHECK HARNESS AND CONNECTOR (IGCT VOLTAGE) P0A1F
NG -- CHECK FUSE (IGCT, IGCT NO. 2)
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 the cable from the negative (-) battery terminal.
(b) Check that the service plug grip is not installed.
NOTICE:
After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.
(c) Disconnect the A58 connector from the hybrid vehicle control ECU.
(d) Remove the hybrid battery junction block assembly Removal.
(e) Disconnect only the z15 connector of the battery smart unit.
(f) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
(g) Connect the cable to the negative (-) battery terminal.
(h) Turn the power switch on (IG).
(i) Measure the voltage according to the value(s) in the table below.
NOTICE:
After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.
Standard Voltage:
NOTICE:
* If the power switch is turned on (IG) with the service plug grip removed, DTCs will be stored. If DTCs are output, clear the DTCs using the Techstream
* If the power switch is turned on (IG) with the connector removed from the sensor, DTCs will be stored. If DTC are stored, clear the DTCs using the Techstream.
(j) Connect the z15 connector of the battery smart unit.
(k) Install the hybrid battery junction block assembly Installation.
(l) Connect the A58 connector to the hybrid vehicle control ECU.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. CHECK WAVEFORM
CAUTION:
Be sure to wear insulated gloves.
(a) Disconnect the cable from the negative (-) battery terminal.
(b) Check that the service plug grip is not installed.
NOTICE:
After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.
(c) Remove the hybrid battery junction block assembly Removal.
(d) Connect the cable to the negative (-) battery terminal.
(e) Connect an oscilloscope between the battery smart unit terminals specified in the table below, and measure the waveform.
NOTICE:
* After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.
* If the power switch is turned on (IG) with the service plug grip removed, DTCs will be stored. If DTCs are output, clear the DTCs using the Techstream
Text in Illustration
(f) Turn the power switch off.
(g) Disconnect the cable from the negative (-) battery terminal.
(h) Install the hybrid battery junction block assembly Installation.
(i) Connect the cable to the negative (-) battery terminal.
NG -- REPLACE BATTERY SMART UNIT Components
OK -- REPLACE HYBRID VEHICLE CONTROL ECU Components
4. CHECK FUSE (IGCT, IGCT NO. 2) P0A1F
NG -- REPLACE FUSE (IGCT, IGCT NO. 2)
OK -- Continue to next step.
5. CHECK RELAY (IGCT) P0A1F
NG -- REPLACE RELAY (IGCT)
OK -- Continue to next step.
6. CHECK HARNESS AND CONNECTOR (IGCT RELAY - BATTERY SMART UNIT) P0A1F
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- CHECK AND REPAIR POWER SOURCE CIRCUIT