Toyota CH-R Service Manual: Open in Bus 1 Main Bus Line

Toyota CH-R Service Manual / Networking / Can Communication System / 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.
  • CAN main bus lines or connector
  • Central gateway ECU (network gateway ECU)
  • No. 1 CAN junction connector
  • No. 6 CAN junction connector

    (w/ Blind Spot Monitor System)

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/o Blind Spot Monitor System

w/ Blind Spot Monitor System

CAUTION / NOTICE / HINT

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 (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.
  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

    Click here

  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

    DTC check procedure: Turn the blind spot monitor system on using the blind spot monitor main switch (ON/OFF switch), turn the cruise control main switch on, turn the LDA main switch on and then drive the vehicle at a speed of 40 km/h (25 mph) or more for approximately 52 seconds 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

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/o Blind Spot Monitor System

A

w/ Blind Spot Monitor System

B
B

GO TO STEP 4

A

2.

CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 1 CAN JUNCTION CONNECTOR)

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

(b) Disconnect the No. 1 CAN junction connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Connected to

F112-4 (CANH) - F112-15 (CANL)

Cable disconnected from negative (-) battery terminal

108 to 132 Ω

Central gateway ECU (network gateway ECU)

F112-5 (CANH) - F112-16 (CANL)

Cable disconnected from negative (-) battery terminal

108 to 132 Ω

Central gateway ECU (network gateway ECU)

*a

Front view of wire harness connector

(to No. 1 CAN Junction Connector)

*b

to Central Gateway ECU (Network Gateway ECU)
OK

REPLACE NO. 1 CAN JUNCTION CONNECTOR
NG

3.

CHECK FOR OPEN IN CAN MAIN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 1 CAN JUNCTION CONNECTOR)

(a) Reconnect the F112 No. 1 CAN junction connector.

(b) Disconnect the central gateway ECU (network gateway ECU) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

F74-23 (CA1H) - F74-9 (CAXH)

Cable disconnected from negative (-) battery terminal

Below 1 Ω

F74-8 (CA1L) - F74-24 (CAXL)

Cable disconnected from negative (-) battery terminal

Below 1 Ω

*a

Front view of wire harness connector

to Central Gateway ECU (Network Gateway ECU)
OK

REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)

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. 6 CAN JUNCTION CONNECTOR)

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

(b) Disconnect the No. 6 CAN junction connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Connected to

M92-1 (CANH) - M92-12 (CANL)

Cable disconnected from negative (-) battery terminal

108 to 132 Ω

Central gateway ECU (network gateway ECU)

M92-11 (CANH) - M92-22 (CANL)

Cable disconnected from negative (-) battery terminal

108 to 132 Ω

No. 1 CAN junction connector

*a

Front view of wire harness connector

(to No. 6 CAN Junction Connector)

*b

to Central Gateway ECU (Network Gateway ECU)

*c

to No. 1 CAN Junction Connector

Result

Proceed to

OK

A

NG (Line to central gateway ECU (network gateway ECU))

B

NG (Line to No. 1 CAN junction connector)

C
A

REPLACE NO. 6 CAN JUNCTION CONNECTOR
C

GO TO STEP 6

B

5.

CHECK FOR OPEN IN CAN MAIN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 6 CAN JUNCTION CONNECTOR)

(a) Reconnect the M92 No. 6 CAN junction connector.

(b) Disconnect the central gateway ECU (network gateway ECU) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

F74-23 (CA1H) - F74-9 (CAXH)

Cable disconnected from negative (-) battery terminal

Below 1 Ω

F74-8 (CA1L) - F74-24 (CAXL)

Cable disconnected from negative (-) battery terminal

Below 1 Ω

*a

Front view of wire harness connector

(to Central Gateway ECU (Network Gateway ECU))
OK

REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)

NG

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 6 CAN JUNCTION CONNECTOR)

6.

CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 1 CAN JUNCTION CONNECTOR)

(a) Reconnect the M92 No. 6 CAN junction connector.

(b) Disconnect the No. 1 CAN junction connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Connected to

F112-4 (CANH) - F112-15 (CANL)

Cable disconnected from negative (-) battery terminal

108 to 132 Ω

No. 6 CAN junction connector

F112-5 (CANH) - F112-16 (CANL)

Cable disconnected from negative (-) battery terminal

108 to 132 Ω

Central gateway ECU (network gateway ECU)

*a

Front view of wire harness connector

(to No. 1 CAN Junction Connector)

*b

to No. 6 CAN Junction Connector

*c

to Central Gateway ECU (Network Gateway ECU)

Result

Proceed to

OK

A

NG (Line to No. 6 CAN junction connector)

B

NG (Line to central gateway ECU (network gateway ECU))

C
A

REPLACE NO. 1 CAN JUNCTION CONNECTOR
B

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (NO. 1 CAN JUNCTION CONNECTOR - NO. 6 CAN JUNCTION CONNECTOR)
C

7.

CHECK FOR OPEN IN CAN MAIN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 1 CAN JUNCTION CONNECTOR)

(a) Reconnect the F112 No. 1 CAN junction connector.

(b) Disconnect the central gateway ECU (network gateway ECU) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

F74-23 (CA1H) - F74-9 (CAXH)

Cable disconnected from negative (-) battery terminal

Below 1 Ω

F74-8 (CA1L) - F74-24 (CAXL)

Cable disconnected from negative (-) battery terminal

Below 1 Ω

*a

Front view of wire harness connector

(to Central Gateway ECU (Network Gateway ECU))
OK

REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)

NG

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 1 CAN JUNCTION CONNECTOR)
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