- CAN main bus lines or connector
- Central gateway ECU (network gateway ECU)
- No. 1 CAN junction connector
-
No. 7 CAN junction connector
(w/ Blind Spot Monitor System)
-
CAN junction terminal
(w/ Blind Spot Monitor System)
| Last Modified: 07-31-2024 | 6.11:8.1.0 | Doc ID: RM100000001GVYY |
| Model Year Start: 2020 | Model: Corolla | Prod Date Range: [01/2019 - 09/2022] |
| Title: NETWORKING: CAN COMMUNICATION SYSTEM (for HV Model): Open in Bus 1 Main Bus Line; 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022] | ||
|
Open in Bus 1 Main Bus Line |
DESCRIPTION
There may be an open circuit in one of the CAN main bus lines when the resistance between terminals 23 (CA1H) and 8 (CA1L) of the central gateway ECU (network gateway ECU) is 70 Ω or higher.
|
Symptom |
Trouble Area |
|---|---|
|
Resistance between terminals 23 (CA1H) and 8 (CA1L) of the central gateway ECU (network gateway ECU) is 70 Ω or higher. |
|
This malfunction is not related to the lines of a CAN branch or to ECUs or sensors connected to a CAN branch.
WIRING DIAGRAM
w/ Blind Spot Monitor System
w/o Blind Spot Monitor System
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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![2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; 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 10 minutes 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 VEHICLE TYPE |
(a) Check vehicle type.
|
Result |
Proceed to |
|---|---|
|
w/ Blind Spot Monitor System |
A |
|
w/o Blind Spot Monitor System |
B |
| B |
|
|
|
2. |
CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 1 CAN JUNCTION CONNECTOR) |
(a) Disconnect the cable from the negative (-) auxiliary battery terminal.
(b) Disconnect the I91 No. 1 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. 1 CAN Junction Connector) |
*b |
to Central Gateway ECU (Network Gateway ECU) |
|
*c |
to No. 7 CAN Junction Connector |
- |
- |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
Connected to |
|---|---|---|---|
|
I91-1 (CANH) - I91-7 (CANL) |
Cable disconnected from negative (-) auxiliary battery terminal |
108 to 132 Ω |
Central gateway ECU (network gateway ECU) |
|
I91-6 (CANH) - I91-12 (CANL) |
Cable disconnected from negative (-) auxiliary battery terminal |
108 to 132 Ω |
No. 7 CAN junction connector |
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (Line to central gateway ECU (network gateway ECU)) |
B |
|
NG (Line to No. 7 CAN junction connector) |
C |
| A |
|
REPLACE NO. 1 CAN JUNCTION CONNECTOR |
| C |
|
|
|
3. |
CHECK FOR OPEN IN CAN MAIN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 1 CAN JUNCTION CONNECTOR) |
(a) Reconnect the I91 No. 1 CAN junction connector.
(b) Disconnect the I53 central gateway ECU (network gateway ECU) connector.
|
(c) Measure the resistance according to the value(s) in the table below. Standard Resistance:
|
|
| OK |
|
| NG |
|
REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 1 CAN JUNCTION CONNECTOR) |
|
4. |
CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 7 CAN JUNCTION CONNECTOR) |
(a) Reconnect the I91 No. 1 CAN junction connector.
(b) Disconnect the O121 No. 7 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. 7 CAN Junction Connector) |
*b |
to No. 1 CAN Junction Connector |
|
*c |
to CAN Junction Terminal |
- |
- |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
Connected to |
|---|---|---|---|
|
O121-2 (CANH) - O121-13 (CANL) |
Cable disconnected from negative (-) auxiliary battery terminal |
108 to 132 Ω |
No. 1 CAN junction connector |
|
O121-3 (CANH) - O121-14 (CANL) |
Cable disconnected from negative (-) auxiliary battery terminal |
108 to 132 Ω |
CAN junction terminal |
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (Line to No. 1 CAN junction connector) |
B |
|
NG (Line to CAN junction terminal) |
C |
| A |
|
REPLACE NO. 7 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (NO. 7 CAN JUNCTION CONNECTOR - NO. 1 CAN JUNCTION CONNECTOR) |
|
|
5. |
CHECK FOR OPEN IN CAN MAIN BUS LINES (CAN JUNCTION TERMINAL - NO. 7 CAN JUNCTION CONNECTOR) |
(a) Reconnect the O121 No. 7 CAN junction connector.
(b) Disconnect the O95 CAN junction terminal connector.
|
(c) Measure the resistance according to the value(s) in the table below. Standard Resistance:
|
|
| OK |
|
REPLACE CAN JUNCTION TERMINAL |
| NG |
|
REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CAN JUNCTION TERMINAL - NO. 7 CAN JUNCTION CONNECTOR) |
|
6. |
CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 1 CAN JUNCTION CONNECTOR) |
(a) Disconnect the cable from the negative (-) auxiliary battery terminal.
(b) Disconnect the I91 No. 1 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. 1 CAN Junction Connector) |
*b |
to Central Gateway ECU (Network Gateway ECU) |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
I91-1 (CANH) - I91-7 (CANL) |
Cable disconnected from negative (-) auxiliary battery terminal |
108 to 132 Ω |
|
I91-6 (CANH) - I91-12 (CANL) |
Cable disconnected from negative (-) auxiliary battery terminal |
108 to 132 Ω |
| OK |
|
REPLACE NO. 1 CAN JUNCTION CONNECTOR |
|
|
7. |
CHECK FOR OPEN IN CAN MAIN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 1 CAN JUNCTION CONNECTOR) |
(a) Reconnect the I91 No. 1 CAN junction connector.
(b) Disconnect the I53 central gateway ECU (network gateway ECU) connector.
|
(c) Measure the resistance according to the value(s) in the table below. Standard Resistance:
|
|
| OK |
|
| NG |
|
REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 1 CAN JUNCTION CONNECTOR) |
|
|