Inspection Procedure

NOTE:

Turn the engine switch off before measuring the resistance of CAN bus main wires and CAN bus branch wires.
After the engine 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 engine switch, any other switches, or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.

HINT:

Operating the engine switch, any switches, or any doors triggers related ECU and sensor communication with the CAN. This communication will cause the resistance value to change.

CHECK WIRE HARNESS (+B, +B2, E1)

Turn the engine switch off.
Disconnect the ECM connectors (E6) and (A6).

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

Fig 1: Identifying ECM E6 Connector Terminal And A6 Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

RESISTANCE REFERENCE

Tester Connection	Condition	Specified Value
E6-1 (E1) - Body ground	Always	Below 1 Ω

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

Standard Voltage

VOLTAGE SPECIFICATION

Tester Connection	Condition	Specified Value
A6-1 (+B2) - Body ground	Engine switch off	10 to 14 V
A6-2 (+B) - Body ground	Engine switch off	10 to 14 V

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE ECM (See REMOVAL )