Inspection Procedure

NOTE:

Turn the ignition switch off before measuring the resistances of the CAN main wire and the CAN branch wire.
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 doors need to be opened in order to check connectors, open the doors and leave them open.
HINT:

Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

CHECK CAN BUS LINE FOR DISCONNECTION (ECM MAIN WIRE)

Measure the resistance according to the value in the table below

Standard resistance

RESISTANCE SPECIFICATION

Tester Connection	Switch Condition	Specified Condition
A21-41 (CANH) - A21-49 (CANL)	Ignition switch off	108 to 132 Ω

NG: REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ECM (CAN-H, CAN-L)

Fig 1: Identifying ECM Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (IGSW, E1)

Measure the resistance according to the value in the table below.

Standard resistance

RESISTANCE SPECIFICATION

Tester Connection	Condition	Specified Condition
C19-104 (E1) - Body ground	Always	Below 1 Ω

Measure the voltage according to the value in the table below.

Standard voltage

VOLTAGE SPECIFICATION

Tester Connection	Switch Condition	Specified Condition
A21-28 (IGSW) - Body ground	Ignition switch on	11 to 14 V

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

Fig 2: Identifying ECM Connector Terminals

OK : REPLACE ECM (See REMOVAL )