Inspection Procedure

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

CHECK WIRE HARNESS AND CONNECTOR (DISTANCE CONTROL ECU - LASER SENSOR)

Disconnect the distance control ECU and laser sensor connectors.

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

Standard resistance

RESISTANCE REFERENCE

Tester Connections	Condition	Specified value
A20-23 (LRRD) - A36-4 (LRRD)	Always	Below 1 Ω
A20-13 (IGB) - A36-5 (IGB)	Always	Below 1 Ω
A20-23 (LRRD) - Body ground	Always	10 kΩ or higher
A20-13 (IGB) - Body ground	Always	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

Fig 1: Identifying A20 And A36 Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to next step

INSPECT DISTANCE CONTROL ECU

Reconnect the distance control ECU connector.
Turn the ignition switch on (IG).

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

Standard voltage

VOLTAGE SPECIFICATION

Tester Connections	Condition	Specified Value
A20-13 (IGB) - Body ground	Ignition SW ON (IG)	10 to 14 V

Check the signal waveform between terminal LRRD (A20-23) of the distance control ECU and body ground.
OK:

A waveform similar to that in the illustration to the left is output.

HINT:
- Gauge set: 2 V/DIV, 5 ms/DIV
- Condition: Ignition switch on (IG)

NG: REPLACE DISTANCE CONTROL ECU

Fig 2: Identifying A20 Connector Terminal

OK : REPLACE LASER SENSOR