Electronic Controlled Automatic Transmission System Pattern Select Switch Power Mode Circuit

Transmission. Lexus Gs430, Gs300. Uzs190 Grs190
A761E Automatic Transmission. Lexus Gs430, Gs300. Uzs190 Grs190

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK HARNESS AND CONNECTOR (PATTERN SELECT SWITCH ASSEMBLY - BODY GROUND)

INSPECT PATTERN SELECT SWITCH ASSEMBLY

CHECK HARNESS AND CONNECTOR (PATTERN SELECT SWITCH ASSEMBLY - MULTIPLEX NETWORK BODY ECU)

ELECTRONIC CONTROLLED AUTOMATIC TRANSMISSION SYSTEM - Pattern Select Switch Power Mode Circuit


DESCRIPTION

Cowl side J/B ECU receives pattern select switch information, and sends it through the multiplex communication system and CAN system to the ECM.
The ECM memory contains the programs for the NORMAL and POWER shift patterns and lock-up pattern.
By following the programs corresponding to the signals from the pattern select switch, the neutral start and other various sensors, the ECM switches the solenoid valves ON and OFF, and controls the transmission gear change and the lock-up clutch operation.

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.A761E Automatic Transmission.Electronic Controlled Automatic Transmission System.Electronic Controlled Automatic Transmission System Pattern Select Switch Power Mode Circuit


INSPECTION PROCEDURE

1.CHECK HARNESS AND CONNECTOR (PATTERN SELECT SWITCH ASSEMBLY - BODY GROUND)

  1. Disconnect the connector of pattern select switch.



    Lexus Gs430, Gs300. Uzs190 Grs190.A761E Automatic Transmission.Electronic Controlled Automatic Transmission System.Electronic Controlled Automatic Transmission System Pattern Select Switch Power Mode Circuit

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

    Resistance:
    Tester Connection
    		Specified Condition
    3*1 - Body ground
    		Below 1 Ω
    5*2 - Body ground
    		Below 1 Ω
    *1: w/ Snow mode switch
    *2: w/o Snow mode switch


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.INSPECT PATTERN SELECT SWITCH ASSEMBLY


    Lexus Gs430, Gs300. Uzs190 Grs190.A761E Automatic Transmission.Electronic Controlled Automatic Transmission System.Electronic Controlled Automatic Transmission System Pattern Select Switch Power Mode Circuit

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

    Resistance:
    Switch Condition
    		Tester Connection
    		Specified Condition
    Pattern select switch
    (PWR)
    		3*1 - 7
    5*2 - 7
    		Below 1 Ω
    Pattern select switch
    (NORM)
    		↑
    		10 kΩ or higher
    *1: w/ Snow mode switch
    *2: w/o Snow mode switch


NG
REPLACE PATTERN SELECT SWITCH ASSEMBLY
OK


3.CHECK HARNESS AND CONNECTOR (PATTERN SELECT SWITCH ASSEMBLY - MULTIPLEX NETWORK BODY ECU)


    Lexus Gs430, Gs300. Uzs190 Grs190.A761E Automatic Transmission.Electronic Controlled Automatic Transmission System.Electronic Controlled Automatic Transmission System Pattern Select Switch Power Mode Circuit

  1. Connect the connector of pattern select switch.

  1. Disconnect the cowl side junction block (multiplex network body ECU) connector.

  1. Measure the resistance between terminal PWR of the cowl side junction block (multiplex network body ECU) and body ground.

    Resistance:
    Switch Condition
    		Tester Connection
    		Specified Condition
    Pattern select switch
    (PWR)
    		L68 - 18 (PWR) - Body ground
    		Below 1 Ω
    Pattern select switch
    (NORM)
    		↑
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE