Inspection Procedure

WARNING: This page is about a different car, the 2003 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

In case of using the LEXUS hand-held tester, start the inspection step 1 and in case of not using the LEXUS hand-held tester, start form step 2.

Check solenoid using LEXUS hand-held tester.
PREPARATION:

Connect the LEXUS hand-held tester to the DLC3.

CHECK:

Check the solenoid using DATA LIST.
1. OK : Check and replace A/C ECU.
2. NG : Go to next step.
Check voltage between terminals SOL+ and SOL- of A/C ECU connector.
PREPARATION:

Remove A/C ECU with connectors still connected.

CHECK:
1. Start the engine.
2. Push AUTO SW.
3. Measure voltage between terminals SOL+ and SOL- of A/C ECU connector.
OK:

Voltage: Below 1.0 V

HINT:

As the temperature increases, the voltage decreases.

Fig 1: Identifying Terminals Sol+ And Sol- Of A/C ECU Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. OK : Proceed to next circuit inspection shown on problem symptom table (See PROBLEM SYMPTOMS TABLE ).
2. NG : Go to next step.
Check solenoid of the externally changeable compressor.
PREPARATION:

Disconnect solenoid of the externally changeable connector.

CHECK:

Measure resistance between terminals 1 and 2 of solenoid of the externally changeable.

OK:

Resistance: at 20°C (68°F) 10 - 11 D.

Fig 2: Disconnecting Solenoid Of Externally Changeable Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. NG : Replace compressor.
2. OK : Go to next step.
Check harness and connectors between A/C ECU and solenoid of the externally changeable compressor (See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE ).
1. NG : Repair or replace harness or connector.
2. OK : Check and replace A/C ECU.