Inspection Procedure

NOTE:

Turn the ignition switch off before measuring the resistance of CAN bus main wires and the CAN bus branch wires.
After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.
Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches or the doors. If any doors need to be opened in order to check the connectors, open the doors and leave them open.

HINT:

Operating the ignition switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below will help determine the cause of the malfunction.

CHECK FOR OPEN IN CAN NO. 1 BUS MAIN WIRE (ECM MAIN WIRE)

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

Standard Resistance

RESISTANCE SPECIFIED CONDITIONS

Tester Connection	Switch Condition	Specified Condition
A37-41 (CANH) - A37-49 (CANL)	Ignition switch off	108 to 132 Ω

Fig 1: Identifying Terminal CANH And CANL Of ECM Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to Next Step

CHECK WIRE HARNESS (POWER SOURCE CIRCUIT)

Check the ECM power source circuit (See INSPECTION PROCEDURE for 2ZR-FE, See INSPECTION PROCEDURE for 2AZ-FE).

Result

RESULT CHART

B: REPLACE ECM (See REMOVAL )

C: REPAIR OR REPLACE HARNESS OR CONNECTOR

A: REPLACE ECM (See REMOVAL )