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 CAN BUS WIRE FOR DISCONNECTION (SKID CONTROL ECU BRANCH WIRE)

Turn the ignition switch off.
Disconnect the skid control ECU connector.

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

Standard Resistance

w/VSC

RESISTANCE SPECIFIED CONDITIONS

Tester Connection	Switch Condition	Specified Condition
A38-25 (CANH) - A38-14 (CANL)	Ignition switch off	54 to 69 Ω

w/o VSC

RESISTANCE SPECIFIED CONDITIONS

Tester Connection	Switch Condition	Specified Condition
A39-25 (CANH) - A39-14 (CANL)	Ignition switch off	54 to 69 Ω

Fig 1: Identifying Skid Control ECU Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (SKID CONTROL ECU BRANCH WIRE)

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (IG1, GND1)

Disconnect the skid control ECU connector.

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

Standard Resistance

w/VSC

RESISTANCE SPECIFIED CONDITIONS

Tester Connection	Condition	Specified Condition
A38-1 (GND1) - Body ground	Always	Below 1 Ω

w/o VSC

RESISTANCE SPECIFIED CONDITIONS

Tester Connection	Condition	Specified Condition
A39-1 (GND1) - Body ground	Always	Below 1 Ω

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

Fig 2: Identifying Terminal IG1 And GND1 Of Skid Control ECU Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Voltage

w/VSC

VOLTAGE SPECIFIED CONDITIONS

Tester Connection	Switch Condition	Specified Condition
A38-34 (IG1) - Body ground	Ignition switch ON	10 to 14 V

w/o VSC

VOLTAGE SPECIFIED CONDITIONS

Tester Connection	Switch Condition	Specified Condition
A39-34 (IG1) - Body ground	Ignition switch on (IG)	10 to 14 V

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to Next Step

CHECK DTC OUTPUT

Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Enter the following menu items: Chassis / ABS/VSC/ TRC / DTC.

Read the DTC.

OK: C1241 is not stored .

Result

RESULT CHART

Result	Proceed to
OK (w/ VSC)	A
OK (w/o VSC)	B
NG (w/ VSC)	C
NG (w/o VSC)	D

B: REPLACE BRAKE ACTUATOR ASSEMBLY (See REMOVAL )

C: GO TO DTC CHART (See DTC C1241/41 LOW BATTERY POSITIVE VOLTAGE OR ABNORMALLY HIGH BATTERY POSITIVE VOLTAGE )

D: GO TO DTC CHART (See DTC C1241/41 LOW BATTERY POSITIVE VOLTAGE OR ABNORMALLY HIGH BATTERY POSITIVE VOLTAGE )

A: REPLACE BRAKE ACTUATOR ASSEMBLY (See REMOVAL )