NETWORKING: CAN COMMUNICATION SYSTEM (for HV Model): U01BD87,U115087,U117B87; Lost Communication with DC/DC Converter Control Module "C" Missing Message; 2023 - 2026 MY Corolla Corolla HV [09/2022 - ]

Last Modified: 08-22-2025	6.11:8.1.0	Doc ID: RM10000000259QY
Model Year Start: 2023	Model: Corolla	Prod Date Range: [09/2022 - ]
Title: NETWORKING: CAN COMMUNICATION SYSTEM (for HV Model): U01BD87,U115087,U117B87; Lost Communication with DC/DC Converter Control Module "C" Missing Message; 2023 - 2026 MY Corolla Corolla HV [09/2022 - ]

DTC

U01BD87

Lost Communication with DC/DC Converter Control Module "C" Missing Message

DTC

U115087

Lost Communication with Hybrid Powertrain Control Module (ch2) Missing Message

DTC

U117B87

Lost Communication with Hybrid/EV Battery Energy Control Module "A" (ch2) Missing Message

DESCRIPTION

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Note
U01BD87	Lost Communication with DC/DC Converter Control Module "C" Missing Message	Communication stops between the hybrid vehicle control ECU and the inverter with converter assembly.	CAN main/branch bus lines or connector Hybrid vehicle control ECU Inverter with converter assembly No. 11 CAN junction connector	DTC Output from Hybrid vehicle control ECU
U115087	Lost Communication with Hybrid Powertrain Control Module (ch2) Missing Message	Communication stops between the battery ECU assembly and the hybrid vehicle control ECU.	CAN main/branch bus lines or connector Battery ECU assembly Hybrid vehicle control ECU No. 11 CAN junction connector	DTC Output from Battery ECU assembly
U117B87	Lost Communication with Hybrid/EV Battery Energy Control Module "A" (ch2) Missing Message	Communication stops between the hybrid vehicle control ECU and the battery ECU assembly.	CAN main/branch bus lines or connector Hybrid vehicle control ECU Battery ECU assembly No. 11 CAN junction connector	DTC Output from Hybrid vehicle control ECU

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

NOTICE:

Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.
Click here
Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) auxiliary battery terminal and leave the vehicle for 10 minutes or more before measuring the resistance.
After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.
Click here
When disconnecting and reconnecting the auxiliary battery.
HINT:

When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.

Click here
Some parts must be initialized and set when replacing or removing and installing parts.
Click here
After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.
DTC check procedure: Turn the ignition switch to ON and wait for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes or more.
After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.
Click here
Before replacing the hybrid vehicle control ECU, refer to Registration.
Click here

HINT:

Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.
When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.

PROCEDURE

1.	CHECK FOR OPEN IN CAN MAIN BUS LINES

(a) Disconnect the cable from the negative (-) auxiliary battery terminal.

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

*a

Component with harness connected

(Hybrid Vehicle Control ECU)

-

-

Standard Resistance:

Tester Connection	Condition	Specified Condition
I3-9 (CA4H) - I3-22 (CA4L)	Cable disconnected from negative (-) auxiliary battery terminal	Below 70 Ω

NG

OK

2.	CHECK FOR SHORT IN CAN BUS LINES

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

*a

Component with harness connected

(Hybrid Vehicle Control ECU)

-

-

Standard Resistance:

Tester Connection	Condition	Specified Condition
I3-9 (CA4H) - I3-22 (CA4L)	Cable disconnected from negative (-) auxiliary battery terminal	54 Ω or higher

NG

OK

3.	CHECK FOR SHORT TO +B IN CAN BUS LINE

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

*a

Component with harness connected

(Hybrid Vehicle Control ECU)

-

-

Standard Resistance:

Tester Connection	Condition	Specified Condition
I3-9 (CA4H) - I3-13 (BATT)	Cable disconnected from negative (-) auxiliary battery terminal	6 kΩ or higher
I3-22 (CA4L) - I3-13 (BATT)		6 kΩ or higher

NG

OK

4.	CHECK FOR SHORT TO GND IN CAN BUS LINE

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

*a

Component with harness connected

(Hybrid Vehicle Control ECU)

-

-

Standard Resistance:

Tester Connection	Condition	Specified Condition
I3-9 (CA4H) - I3-1 (E1)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
I3-22 (CA4L) - I3-1 (E1)		200 Ω or higher

OK

INSPECT FOR INTERMITTENT PROBLEMS

NG

5.	CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - HYBRID VEHICLE CONTROL ECU)

(a) Disconnect the A147 No. 11 CAN junction connector.

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Hybrid Vehicle Control ECU

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-2 (CANH) - I26-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
A147-13 (CANL) - I26-4 (CG)		200 Ω or higher

NG

OK

6.	CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - INVERTER WITH CONVERTER ASSEMBLY)

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Inverter with Converter Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-3 (CANH) - I26-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
A147-14 (CANL) - I26-4 (CG)		200 Ω or higher

NG

OK

7.	CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - BATTERY ECU ASSEMBLY)

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Battery ECU Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-4 (CANH) - I26-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
A147-15 (CANL) - I26-4 (CG)		200 Ω or higher

OK

REPLACE NO. 11 CAN JUNCTION CONNECTOR

NG

8.	CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - HYBRID VEHICLE CONTROL ECU)

(a) Disconnect the I3 hybrid vehicle control ECU connector.

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Hybrid Vehicle Control ECU

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-2 (CANH) - I26-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
A147-13 (CANL) - I26-4 (CG)		200 Ω or higher

OK

REPLACE HYBRID VEHICLE CONTROL ECU

NG

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 11 CAN JUNCTION CONNECTOR - HYBRID VEHICLE CONTROL ECU)

9.	CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - INVERTER WITH CONVERTER ASSEMBLY)

(a) Disconnect the A156 inverter with converter assembly connector.

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

Inverter with Converter Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-3 (CANH) - I26-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
A147-14 (CANL) - I26-4 (CG)		200 Ω or higher

OK

REPLACE INVERTER WITH CONVERTER ASSEMBLY

NG

REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (NO. 11 CAN JUNCTION CONNECTOR - INVERTER WITH CONVERTER ASSEMBLY)

10.	CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - BATTERY ECU ASSEMBLY)

(a) Disconnect the O192 battery ECU assembly connector.

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Battery ECU Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-4 (CANH) - I26-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
A147-15 (CANL) - I26-4 (CG)		200 Ω or higher

OK

REPLACE BATTERY ECU ASSEMBLY

NG

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 11 CAN JUNCTION CONNECTOR - BATTERY ECU ASSEMBLY)

11.	CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - HYBRID VEHICLE CONTROL ECU)

(a) Disconnect the A147 No. 11 CAN junction connector.

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Hybrid Vehicle Control ECU

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-2 (CANH) - I26-16 (BAT)	Cable disconnected from negative (-) auxiliary battery terminal	6 kΩ or higher
A147-13 (CANL) - I26-16 (BAT)		6 kΩ or higher

NG

OK

12.	CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - INVERTER WITH CONVERTER ASSEMBLY)

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Inverter with Converter Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-3 (CANH) - I26-16 (BAT)	Cable disconnected from negative (-) auxiliary battery terminal	6 kΩ or higher
A147-14 (CANL) - I26-16 (BAT)		6 kΩ or higher

NG

OK

13.	CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - BATTERY ECU ASSEMBLY)

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Battery ECU Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-4 (CANH) - I26-16 (BAT)	Cable disconnected from negative (-) auxiliary battery terminal	6 kΩ or higher
A147-15 (CANL) - I26-16 (BAT)		6 kΩ or higher

OK

REPLACE NO. 11 CAN JUNCTION CONNECTOR

NG

14.	CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - HYBRID VEHICLE CONTROL ECU)

(a) Disconnect the I3 hybrid vehicle control ECU connector.

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Hybrid Vehicle Control ECU

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-2 (CANH) - I26-16 (BAT)	Cable disconnected from negative (-) auxiliary battery terminal	6 kΩ or higher
A147-13 (CANL) - I26-16 (BAT)		6 kΩ or higher

OK

REPLACE HYBRID VEHICLE CONTROL ECU

NG

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 11 CAN JUNCTION CONNECTOR - HYBRID VEHICLE CONTROL ECU)

15.	CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - INVERTER WITH CONVERTER ASSEMBLY)

(a) Disconnect the A156 inverter with converter assembly connector.

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Inverter with Converter Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-3 (CANH) - I26-16 (BAT)	Cable disconnected from negative (-) auxiliary battery terminal	6 kΩ or higher
A147-14 (CANL) - I26-16 (BAT)		6 kΩ or higher

OK

REPLACE INVERTER WITH CONVERTER ASSEMBLY

NG

REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (NO. 11 CAN JUNCTION CONNECTOR - INVERTER WITH CONVERTER ASSEMBLY)

16.	CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 11 CAN JUNCTION CONNECTOR - BATTERY ECU ASSEMBLY)

(a) Disconnect the O192 battery ECU assembly connector.

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

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Battery ECU Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-4 (CANH) - I26-16 (BAT)	Cable disconnected from negative (-) auxiliary battery terminal	6 kΩ or higher
A147-15 (CANL) - I26-16 (BAT)		6 kΩ or higher

OK

REPLACE BATTERY ECU ASSEMBLY

NG

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 11 CAN JUNCTION CONNECTOR - BATTERY ECU ASSEMBLY)

17.	CHECK FOR SHORT IN CAN BUS LINES (NO. 11 CAN JUNCTION CONNECTOR - HYBRID VEHICLE CONTROL ECU)

(a) Disconnect the A147 No. 11 CAN junction connector.

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

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Hybrid Vehicle Control ECU

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-2 (CANH) - A147-13 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	108 to 132 Ω

NG

OK

18.	CHECK FOR SHORT IN CAN BUS LINES (NO. 11 CAN JUNCTION CONNECTOR - INVERTER WITH CONVERTER ASSEMBLY)

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

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Inverter with Converter Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-3 (CANH) - A147-14 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher

NG

OK

19.	CHECK FOR SHORT IN CAN BUS LINES (NO. 11 CAN JUNCTION CONNECTOR - BATTERY ECU ASSEMBLY)

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

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Battery ECU Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-4 (CANH) - A147-15 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	108 to 132 Ω

OK

REPLACE NO. 11 CAN JUNCTION CONNECTOR

NG

20.	CHECK FOR SHORT IN CAN BUS LINES (NO. 11 CAN JUNCTION CONNECTOR - HYBRID VEHICLE CONTROL ECU)

(a) Disconnect the I3 hybrid vehicle control ECU connector.

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

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Hybrid Vehicle Control ECU

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-2 (CANH) - A147-13 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	1 MΩ or higher

OK

REPLACE HYBRID VEHICLE CONTROL ECU

NG

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (NO. 11 CAN JUNCTION CONNECTOR - HYBRID VEHICLE CONTROL ECU)

21.	CHECK FOR SHORT IN CAN BUS LINES (NO. 11 CAN JUNCTION CONNECTOR - INVERTER WITH CONVERTER ASSEMBLY)

(a) Disconnect the A156 inverter with converter assembly connector.

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

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Inverter with Converter Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-3 (CANH) - A147-14 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	1 MΩ or higher

OK

REPLACE INVERTER WITH CONVERTER ASSEMBLY

NG

REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (NO. 11 CAN JUNCTION CONNECTOR - INVERTER WITH CONVERTER ASSEMBLY)

22.	CHECK FOR SHORT IN CAN BUS LINES (NO. 11 CAN JUNCTION CONNECTOR - BATTERY ECU ASSEMBLY)

(a) Disconnect the O192 battery ECU assembly connector.

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

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Battery ECU Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-4 (CANH) - A147-15 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	1 MΩ or higher

OK

REPLACE BATTERY ECU ASSEMBLY

NG

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (NO. 11 CAN JUNCTION CONNECTOR - BATTERY ECU ASSEMBLY)

23.	CHECK FOR OPEN IN CAN MAIN BUS LINES (HYBRID VEHICLE CONTROL ECU)

(a) Disconnect the I3 hybrid vehicle control ECU connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
I3-9 (CA4H) - I3-22 (CA4L)	Cable disconnected from negative (-) auxiliary battery terminal	108 to 132 Ω

*a	Front view of wire harness connector (to Hybrid Vehicle Control ECU)

OK

REPLACE HYBRID VEHICLE CONTROL ECU

NG

24.	CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 11 CAN JUNCTION CONNECTOR - HYBRID VEHICLE CONTROL ECU)

(a) Reconnect the I3 hybrid vehicle control ECU connector.

(b) Disconnect the A147 No. 11 CAN junction connector.

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

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Hybrid Vehicle Control ECU

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-2 (CANH) - A147-13 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	108 to 132 Ω

NG

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (NO. 11 CAN JUNCTION CONNECTOR - HYBRID VEHICLE CONTROL ECU)

OK

25.	CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 11 CAN JUNCTION CONNECTOR - BATTERY ECU ASSEMBLY)

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

*a

Front view of wire harness connector

(to No. 11 CAN Junction Connector)

*b

to Battery ECU Assembly

Standard Resistance:

Tester Connection	Condition	Specified Condition
A147-4 (CANH) - A147-15 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	108 to 132 Ω

OK

REPLACE NO. 11 CAN JUNCTION CONNECTOR

NG

26.	CHECK FOR OPEN IN CAN MAIN BUS LINES (BATTERY ECU ASSEMBLY)

(a) Reconnect the A147 No. 11 CAN junction connector.

(b) Disconnect the O192 battery ECU assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
O192-22 (CA1H) - O192-21 (CA1L)	Cable disconnected from negative (-) auxiliary battery terminal	108 to 132 Ω

*a	Front view of wire harness connector (to Battery ECU Assembly)

OK

REPLACE BATTERY ECU ASSEMBLY

NG

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (BATTERY ECU ASSEMBLY - NO. 11 CAN JUNCTION CONNECTOR)