DTC U029A-123: Lost Communication with Hybrid Battery Pack Sensor Module [12/2013 - ]: Procedure

CHECK DTC OUTPUT (HYBRID CONTROL)

Connect the Techstream to the DLC3.
Turn the ignition switch to ON (IG).
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
Check and record any HV system DTCs, INF codes and freeze frame data.

Check for DTCs. Refer to DTC CHECK / CLEAR [12/2013 - ] .

Result

Result	Proceed to
Only U029A-123 is output.	A
DTCs other than U029A-123 are also output.	B

Turn the ignition switch off.
Disconnect the Techstream from the DLC3.

B → See step 6

A: Go to next step

CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BATTERY SMART UNIT)

WARNING:

Be sure to wear insulated gloves.

Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the ignition switch to ON (READY), unless instructed by the repair information because this may cause a malfunction.
Disconnect connector G57 from the power management control ECU. Refer to REMOVAL [12/2013 - ] .
Remove the No. 1 hybrid battery exhaust duct. Refer to REMOVAL [12/2013 - ] - Step 10 .
Disconnect connector M39 from the battery smart unit.

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

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
G57-32 (BTH+) - M39-1 (BTH+)	Ignition switch off	Below 1 Ω
G57-33 (BTH-) - M39-4 (BTH-)	Ignition switch off	Below 1 Ω
M39-1 (BTH+) - M39-6 (GND) and Body ground	Ignition switch off	10 kΩ or higher
M39-4 (BTH-) - M39-6 (GND) and Body ground	Ignition switch off	10 kΩ or higher

TEXT IN ILLUSTRATION

*a	Rear view of wire harness connector (to Power Management Control ECU)
*b	Rear view of wire harness connector (to Battery Smart Unit)

Remove the IG2 No. 2 fuse, IGCT No. 2 fuse, AM2 fuse from the No. 2 engine room relay block and No. 2 junction block assembly. (w/ smart key system)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TEXT IN ILLUSTRATION

*1	No. 2 Engine Room Relay Block and No. 2 Junction Block Assembly
*2	IG2 No. 2 fuse
*3	IGCT No. 2 fuse
*4	AM2 fuse

Remove the IG2 No. 2 fuse, IGCT No. 2 fuse, ECU-B No. 2 fuse from the No. 2 engine room relay block and No. 2 junction block assembly. (w/o smart key system)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TEXT IN ILLUSTRATION

*1	No. 2 Engine Room Relay Block and No. 2 Junction Block Assembly
*2	IG2 No. 2 fuse
*3	IGCT No. 2 fuse
*4	ECU-B No. 2 fuse

Disconnect all connectors from the power management control ECU.

Measure the resistance according to the value(s) in the table below. (w/ smart key system)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TEXT IN ILLUSTRATION

Rear view of wire harness connector
(to Power Management Control ECU)

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
G57-32 (BTH+) - G58-7 (AM21)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - G57-1 (AM22)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - A38-2 (+B2)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - A39-5 (+B1)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - A39-6 (MREL)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - A39-1 (IG2)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - G58-1 (ACCD)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) G58-2 (IG1D)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - A39-2 (IG2D)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - G57-14 (SPDI)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - G58-7 (AM21)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - G57-1 (AM22)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - A38-2 (+B2)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - A39-5 (+B1)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - A39-6 (MREL)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - A39-1 (IG2)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - G58-1 (ACCD)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - G58-2 (IG1D)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - A39-2 (IG2D)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - G57-14 (SPDI)	Ignition switch off	10 kΩ or higher

NOTE:

When taking a measurement with a tester, do not apply excessive force to the tester probe to avoid damaging the holder.

Measure the resistance according to the value(s) in the table below. (w/o smart key system)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TEXT IN ILLUSTRATION

Rear view of wire harness connector
(to Power Management Control ECU)

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
G57-32 (BTH+) - G57-1 (BATT)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - A38-2 (+B2)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - A39-5 (+B1)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - A39-6 (MREL)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - A39-1 (IG2)	Ignition switch off	10 kΩ or higher
G57-32 (BTH+) - G57-14 (SPDI)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - G57-1 (BATT)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - A38-2 (+B2)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - A39-5 (+B1)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - A39-6 (MREL)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - A39-1 (IG2)	Ignition switch off	10 kΩ or higher
G57-33 (BTH-) - G57-14 (SPDI)	Ignition switch off	10 kΩ or higher

NOTE:

When taking a measurement with a tester, do not apply excessive force to the tester probe to avoid damaging the holder.

Connect the battery smart unit connector.
Install the No. 1 hybrid battery exhaust duct.
Connect the power management control ECU connectors.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER MANAGEMENT CONTROL ECU - BATTERY SMART UNIT)

OK: Go to next step

CHECK POWER MANAGEMENT CONTROL ECU

WARNING:

Be sure to wear insulated gloves.

Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the ignition switch to ON (READY), unless instructed by the repair information because this may cause a malfunction.
Remove the No. 1 hybrid battery exhaust duct. Refer to REMOVAL [12/2013 - ] - Step 10 .
Disconnect connector M39 from the battery smart unit.
Connect the cable to the negative (-) auxiliary battery terminal.
Turn the ignition switch to ON (IG).

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

Standard Voltage

Tester Connection	Switch Condition	Specified Condition
M39-1 (BTH+) - M39-6 (GND)	Ignition switch ON (IG)	2.3 to 2.7 V
M39-4 (BTH-) - M39-6 (GND)	Ignition switch ON (IG)	2.3 to 2.7 V

TEXT IN ILLUSTRATION

*a	Rear view of wire harness connector (to Battery Smart Unit)

NOTE:

Turning the ignition switch to ON (IG) with the battery smart unit connector and power management control ECU connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

Turn the ignition switch off.
Disconnect the cable from the negative (-) auxiliary battery terminal.

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

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
M39-1 (BTH+) - M39-4 (BTH-)	Ignition switch off	4.4 to 5.4 kΩ

TEXT IN ILLUSTRATION

*a	Rear view of wire harness connector (to Battery Smart Unit)

HINT:

Resistance becomes 2.0 kΩ or less when there is a short circuit in the power management control ECU.

Connect the battery smart unit connector.
Install the No. 1 hybrid battery exhaust duct.

NG → See step 5

OK → See step 4

REPLACE BATTERY SMART UNIT. Refer to COMPONENTS [12/2013 - ]
REPLACE POWER MANAGEMENT CONTROL ECU. Refer to COMPONENTS [12/2013 - ]
GO TO DTC CHART (HYBRID BATTERY SYSTEM). Refer to DIAGNOSTIC TROUBLE CODE CHART [12/2013 - ]