Inspection Procedure

WARNING: This page is about a different car, the 2009 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.

CHECK BODY ECU

Disconnect the A24 sensor connector.

Measure the voltage of the wire harness side connector.

Standard voltage

TESTER CONNECTION - SPECIFIED CONDITION

Tester Connection	Condition	Specified Condition
1 (CLTB) - 3 (CLTE)	Power switch ON (IG)	10 to 14 V

Fig 1: Identifying A24 Sensor Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG : Go to step 4

OK : GO TO NEXT STEP

CHECK WIRE HARNESS (SENSOR - ECU)

Disconnect the A24 sensor connector.
Disconnect the B6 ECU connector.

Fig 2: Identifying A24 Sensor Connector & B6 ECU Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance of the wire harness side connectors.

Standard resistance

TESTER CONNECTION - SPECIFIED CONDITION

Tester Connection	Specified Condition
A24-4 (CLTS) - B6-15 (CLTS)	Below 1 Ω

NG : REPAIR OR REPLACE HARNESS AND CONNECTOR

OK : GO TO NEXT STEP

REPLACE AUTOMATIC LIGHT CONTROL SENSOR
OK : Returns to normal operation.

NG : REPLACE DRIVER SIDE JUNCTION BLOCK (MAIN BODY ECU)

OK : END

CHECK WIRE HARNESS (SENSOR - BODY GROUND)

Disconnect the A24 ECU connector.

Fig 3: Identifying A24 ECU Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the voltage of the wire harness side connector.

Standard voltage

TESTER CONNECTION - SPECIFIED CONDITION

Tester Connection	Condition	Specified Condition
A24-1 (CLTB) - Body ground	Power switch ON (IG)	10 to 14 V

NG : Go to step 6

OK : GO TO NEXT STEP

CHECK WIRE HARNESS (SENSOR - ECU)

Disconnect the A24 sensor connector.
Disconnect the B6 ECU connector.

Fig 4: Identifying A24 Sensor Connector & B6 ECU Connector

Measure the resistance of the wire harness side connectors.

Standard resistance

TESTER CONNECTION - SPECIFIED CONDITION

Tester Connection	Specified Condition
A24-3 (CLTE) - B6-14 (CLTE)	Below 1 Ω

NG : REPAIR OR REPLACE HARNESS AND CONNECTOR

OK : REPLACE DRIVER SIDE JUNCTION BLOCK (MAIN BODY ECU)

CHECK WIRE HARNESS (SENSOR - ECU)

Disconnect the A24 sensor connector.
Disconnect the B6 ECU connector.

Fig 5: Identifying A24 Sensor Connector & B6 ECU Connector

Measure the resistance of the wire harness side connectors.

Standard resistance

TESTER CONNECTION - SPECIFIED CONDITION

Tester Connection	Specified Condition
A24-1 (CLTB) - B6-16 (CLTB)	Below 1 Ω

NG : REPAIR OR REPLACE HARNESS AND CONNECTOR

OK : REPLACE DRIVER SIDE JUNCTION BLOCK (MAIN BODY ECU)