Toyota Tacoma (2015-2018) Service Manual: Open in Bus 3 Main Bus Line

Toyota Tacoma (2015-2018) Service Manual / Can Communication / Can Communication System / Open in Bus 3 Main Bus Line

DESCRIPTION

There may be an open circuit in one of the CAN main bus lines when the resistance between terminals 6 (CA3H) and 21 (CA3L) of the central gateway ECU (network gateway ECU) is 70 Ω or higher.

Detection Item	Trouble Area
Resistance between terminals 6 (CA3H) and 21 (CA3L) of central gateway ECU (network gateway ECU) is 70 Ω or higher.	CAN main lines or connector Central gateway ECU (network gateway ECU) No. 6 CAN junction connector

This malfunction is not related to the lines of a CAN branch or to ECUs or sensors connected to a CAN branch.

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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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.
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Some parts must be initialized and set when replacing or removing and installing parts.
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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 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.
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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 OPEN IN CAN BUS LINES (NO. 6 CAN JUNCTION CONNECTOR)

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

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

Standard Resistance:

Tester Connection	Condition	Specified Condition	Connected to
J22-9 (CANH) - J22-20 (CANL)	Cable disconnected from negative (-) battery terminal	108 to 132 Ω	Central gateway ECU (network gateway ECU)
J22-10 (CANH) - J22-21 (CANL)	Cable disconnected from negative (-) battery terminal	108 to 132 Ω	Central gateway ECU (network gateway ECU)

Text in Illustration

Front view of wire harness connector

(to No. 6 CAN Junction Connector)

to Central Gateway ECU (Network Gateway ECU)

REPLACE NO. 6 CAN JUNCTION CONNECTOR

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

(a) Reconnect the J22 No. 6 CAN junction connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
N36-6 (CA3H) - N36-19 (CAYH)	Cable disconnected from negative (-) battery terminal	Below 1 Ω
N36-21 (CA3L) - N36-20 (CAYL)	Cable disconnected from negative (-) battery terminal	Below 1 Ω

Text in Illustration

*a	Front view of wire harness connector (to Central Gateway ECU (Network Gateway ECU))

REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)

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

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