- Short to +B in CAN main bus line
- Short to +B in CAN branch line
- Central gateway ECU (network gateway ECU)
- Occupant detection ECU
- Tire pressure warning ECU and receiver
- Rack and pinion power steering gear assembly
- Brake booster with master cylinder assembly
- Steering sensor
- Airbag ECU assembly
- ECM
- Brake actuator assembly
- Hybrid vehicle control ECU
- No. 2 CAN junction connector
- No. 4 CAN junction connector
- No. 1 junction connector
| Last Modified: 08-21-2023 | 6.11:8.1.0 | Doc ID: RM100000001ANDA |
| Model Year Start: 2019 | Model: Avalon HV | Prod Date Range: [04/2018 - ] |
| Title: NETWORKING: CAN COMMUNICATION SYSTEM (for HV Model): Check Bus 4 Line for Short to +B; 2019 - 2022 MY Avalon HV [04/2018 - ] | ||
|
Check Bus 4 Line for Short to +B |
DESCRIPTION
There may be a short circuit between one of the CAN bus lines and +B when there is no resistance between terminal 22 (CA2H) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3, or terminal 7 (CA2L) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3.
|
Symptom |
Trouble Area |
|---|---|
|
There is no resistance between terminal 22 (CA2H) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3, or terminal 7 (CA2L) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3. |
|
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.
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![2019 - 2022 MY Avalon HV [04/2018 - ]; NETWORKING: CAN COMMUNICATION SYSTEM (for HV Model): HOW TO PROCEED WITH TROUBLESHOOTING](/t3Portal/stylegraphics/info.gif)
- Before measuring the resistance of the CAN bus, turn the power 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 1 minute or more before measuring the resistance.
-
After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.
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-
After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.
DTC check procedure: Turn the power switch on (IG) 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.
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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 SHORT TO +B IN CAN BUS LINE (NO. 1 JUNCTION CONNECTOR) |
(a) Disconnect the cable from the negative (-) auxiliary battery terminal.
(b) Disconnect the K67 No. 1 junction connector.
(c) Measure the resistance according to the value(s) in the table below.
|
*1 |
DLC3 |
- |
- |
|
*a |
Front view of wire harness connector (to No. 1 Junction Connector) |
*b |
to Tire Pressure Warning ECU and Receiver |
|
*c |
to Occupant Detection ECU |
*d |
to Central Gateway ECU (Network Gateway ECU) |
|
*e |
to No. 2 CAN Junction Connector |
- |
- |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
Connected to |
|---|---|---|---|
|
K67-8 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
Tire pressure warning ECU and receiver |
|
K67-19 (CANL) - G45-16 (BAT) |
|||
|
K67-9 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
Occupant detection ECU |
|
K67-20 (CANL) - G45-16 (BAT) |
|||
|
K67-10 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
Central gateway ECU (network gateway ECU) |
|
K67-21 (CANL) - G45-16 (BAT) |
|||
|
K67-11 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
No. 2 CAN junction connector |
|
K67-22 (CANL) - G45-16 (BAT) |
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (Line to central gateway ECU (network gateway ECU)) |
B |
|
NG (Line to No. 2 CAN junction connector) |
C |
|
NG (Line to ECU or sensor) |
D |
| A |
|
REPLACE NO. 1 JUNCTION CONNECTOR |
| C |
|
| D |
|
|
|
2. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 1 JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)) |
(a) Disconnect the G52 central gateway ECU (network gateway 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. 1 Junction Connector) |
*b |
to Central Gateway ECU (Network Gateway ECU) |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K67-10 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
|
K67-21 (CANL) - G45-16 (BAT) |
| OK |
|
REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)
|
| NG |
|
REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 1 JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)) |
|
3. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 2 CAN JUNCTION CONNECTOR) |
(a) Disconnect the A49 No. 2 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. 2 CAN Junction Connector) |
*b |
to Brake Booster with Master Cylinder Assembly |
|
*c |
to No. 1 Junction Connector |
*d |
to ECM |
|
*e |
to Rack and Pinion Power Steering Gear Assembly |
*f |
to No. 4 CAN Junction Connector |
|
*g |
to Brake Actuator Assembly |
- |
- |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
Connected to |
|---|---|---|---|
|
A49-1 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
Brake booster with master cylinder assembly |
|
A49-12 (CANL) - G45-16 (BAT) |
|||
|
A49-2 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
No. 1 junction connector |
|
A49-13 (CANL) - G45-16 (BAT) |
|||
|
A49-3 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
ECM |
|
A49-14 (CANL) - G45-16 (BAT) |
|||
|
A49-4 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
Rack and pinion power steering gear assembly |
|
A49-15 (CANL) - G45-16 (BAT) |
|||
|
A49-5 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
No. 4 CAN junction connector |
|
A49-16 (CANL) - G45-16 (BAT) |
|||
|
A49-6 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
Brake actuator assembly |
|
A49-17 (CANL) - G45-16 (BAT) |
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (Line to No. 1 junction connector) |
B |
|
NG (Line to No. 4 CAN junction connector) |
C |
|
NG (Line to ECU or sensor) |
D |
| A |
|
REPLACE NO. 2 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 2 CAN JUNCTION CONNECTOR - NO. 1 JUNCTION CONNECTOR) |
| D |
|
|
|
4. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 4 CAN JUNCTION CONNECTOR) |
(a) Disconnect the G96 No. 4 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. 4 CAN Junction Connector) |
*b |
to Hybrid Vehicle Control ECU |
|
*c |
to Airbag ECU Assembly |
- |
- |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
Connected to |
|---|---|---|---|
|
G96-5 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
Hybrid vehicle control ECU |
|
G96-16 (CANL) - G45-16 (BAT) |
|||
|
G96-6 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
Airbag ECU assembly |
|
G96-17 (CANL) - G45-16 (BAT) |
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (Line to airbag ECU assembly) |
B |
|
NG (Line to ECU or sensor) |
C |
| B |
|
| C |
|
|
|
5. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 4 CAN JUNCTION CONNECTOR) |
(a) Disconnect the G95 No. 4 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. 4 CAN Junction Connector) |
*b |
to No. 2 CAN Junction Connector |
|
*c |
to Steering Sensor |
- |
- |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
Connected to |
|---|---|---|---|
|
G95-6 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
No. 2 CAN junction connector |
|
G95-17 (CANL) - G45-16 (BAT) |
|||
|
G95-7 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
Steering sensor |
|
G95-18 (CANL) - G45-16 (BAT) |
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (Line to No. 2 CAN junction connector) |
B |
|
NG (Line to ECU or sensor) |
C |
| A |
|
REPLACE NO. 4 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 4 CAN JUNCTION CONNECTOR - NO. 2 CAN JUNCTION CONNECTOR) |
| C |
|
|
6. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 4 CAN JUNCTION CONNECTOR - AIRBAG ECU ASSEMBLY) |
(a) Disconnect the G50 airbag 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. 4 CAN Junction Connector) |
*b |
to Airbag ECU Assembly |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
G96-6 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
|
G96-17 (CANL) - G45-16 (BAT) |
| OK |
|
REPLACE AIRBAG ECU ASSEMBLY
|
| NG |
|
REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 4 CAN JUNCTION CONNECTOR - AIRBAG ECU ASSEMBLY) |
|
7. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (ECU OR SENSOR) |
(a) Reconnect all wire harness connectors.
(b) Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the bus line shorted to +B is connected.
Click here
(c) Measure the resistance according to the value(s) in the table below.
|
*1 |
DLC3 |
- |
- |
|
*a |
Component with harness connected (Central Gateway ECU (Network Gateway ECU)) |
- |
- |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
G52-22 (CA2H) - G45-16 (BAT) |
Cable disconnected from negative (-) auxiliary battery terminal |
6 kΩ or higher |
|
G52-7 (CA2L) - G45-16 (BAT) |
HINT:
- If the resistance changes to 6 kΩ or higher when the connector is disconnected from the ECU or sensor, there may be a short in the ECU or sensor.
- If the resistance does not become normal when the connector is disconnected from the ECU or sensor, check for a short to +B in the wire harness and repair or replace the wire harness or connector if necessary.
| OK |
|
REPLACE ECU OR SENSOR |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|