Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota Yaris. However, it is still accessible from the selected car via links, so may be relevant.

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 (AIR CONDITIONING AMPLIFIER BRANCH WIRE)

Turn the ignition switch OFF.
Disconnect the E8 air conditioning amplifier connector.

Measure the resistance.

Standard resistance

RESISTANCE SPECIFICATION CONDITION CHART

Tester Connection	Condition	Specified Condition
E8-2 (TX+) - E8-3 (TX-)	Ignition switch OFF	54 to 69 Ω

Fig 1: Checking CAN Bus Line For Disconnection (Air Conditioning Amplifier Branch Wire)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO AIR CONDITIONING AMPLIFIER (CAN-H, CAN-L)

OK: GO TO NEXT STEP

CHECK HARNESS AND CONNECTOR (IG+, GND)

Disconnect the E8 air conditioning amplifier connector.

Measure the resistance.

Standard resistance

RESISTANCE SPECIFICATION CONDITION CHART

Tester Connection	Condition	Specified Condition
E8-12 (GND) - Body ground	Always	Below 1 Ω

Measure the voltage.

Standard voltage

TESTER CONNECTION SPECIFIED CONDITION

Tester Connection	Condition	Specified Condition
E8-8 (IG+) - Body ground	Ignition switch ON	11 to 14 V

Fig 2: Checking Harness And Connector (IG+, GND)

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE AIR CONDITIONING AMPLIFIER