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.

Check ATF temperature sensor.
PREPARATION:

Disconnect the solenoid wire connector.

CHECK:

Measure resistance between terminals 1 and 7 of the transmission wire connector and body ground.

OK:

Resistance: 1 MΩ or higher

PREPARATION:
1. Remove the oil pan.
2. Disconnect all solenoid valve connectors.
3. Disconnect the ATF temperature sensor.
  
  Fig 1: Disconnecting Solenoid Wire Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
CHECK:

Measure resistance between terminals 1 and 7 of transmission wire connector at 25 °C (77 °F) and 110 °C (230 °F).

OK:

Resistance (Approx.):

25 °C (77 °F): 3.5 kΩ

110 °C (230 °F): 231 - 263 Ω

Fig 2: Measuring Resistance Between Terminals 1 And 7
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. NG : Replace the ATF temperature sensor (transmission wire) (See ATF TEMPERATURE SENSOR ).
2. OK : Go to next step.
Check harness and connector between ECM and transmission wire (See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE ).
1. NG : Repair or replace the harness or connector.
2. OK : Check and replace the ECM (See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE ).