Electronic Controlled Automatic Transmission System Transmission Control Switch Circuit

Transmission. Lexus Gs430, Gs300. Uzs190 Grs190
A960E Automatic Transmission. Lexus Gs430, Gs300. Uzs190 Grs190

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK HARNESS AND CONNECTOR (BATTERY - TRANSMISSION CONTROL SWITCH)

CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - BODY GROUND)

INSPECT TRANSMISSION CONTROL SWITCH

CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - ECM)

ELECTRONIC CONTROLLED AUTOMATIC TRANSMISSION SYSTEM - Transmission Control Switch Circuit


DESCRIPTION

When moving the shift lever into the S position using the transmission control switch, it is possible to switch the shift range position between "1" (first range) and "6" (sixth range).
Shifting up "+" once raises one shift range position, and shifting down "-" lowers one shift range position.

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.A960E Automatic Transmission.Electronic Controlled Automatic Transmission System.Electronic Controlled Automatic Transmission System  Transmission Control Switch Circuit


INSPECTION PROCEDURE

1.CHECK HARNESS AND CONNECTOR (BATTERY - TRANSMISSION CONTROL SWITCH)


    Lexus Gs430, Gs300. Uzs190 Grs190.A960E Automatic Transmission.Electronic Controlled Automatic Transmission System.Electronic Controlled Automatic Transmission System  Transmission Control Switch Circuit
  1. Disconnect the transmission control switch connector of shift lock control unit assembly.

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

    Voltage:
    Switch Condition
    Tester Connection
    Specified Condition
    Engine switch on (IG)
    3 - Body ground
    10 to 14 V
    Engine switch off

    Below 1 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - BODY GROUND)


    Lexus Gs430, Gs300. Uzs190 Grs190.A960E Automatic Transmission.Electronic Controlled Automatic Transmission System.Electronic Controlled Automatic Transmission System  Transmission Control Switch Circuit
  1. Measure the resistance according to the value(s) in the table below.

    Resistance:
    Tester Connection
    Specified Condition
    5 - Body ground
    Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.INSPECT TRANSMISSION CONTROL SWITCH


    Lexus Gs430, Gs300. Uzs190 Grs190.A960E Automatic Transmission.Electronic Controlled Automatic Transmission System.Electronic Controlled Automatic Transmission System  Transmission Control Switch Circuit
  1. Measure resistance between each terminal of shift lock control unit assembly when the shift lever is moved to each position.

    Resistance:
    Shift Position
    Tester Connection
    Specified Condition
    S, "+" and "-"
    3 - 7
    Below 1 Ω
    Except S, "+" and "-"

    10 kΩ or higher
    Press continuously
    "+"
    (Up shift)
    2 - 5
    Below 1 Ω
    S

    10 kΩ or higher
    Press continuously
    "-"
    (Down shift)
    1 - 5
    Below 1 Ω
    S

    10 kΩ or higher


NG
REPLACE TRANSMISSION CONTROL SWITCH
OK


4.CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - ECM)


    Lexus Gs430, Gs300. Uzs190 Grs190.A960E Automatic Transmission.Electronic Controlled Automatic Transmission System.Electronic Controlled Automatic Transmission System  Transmission Control Switch Circuit
  1. Connect the transmission control switch connector of shift lock control unit assembly.

  1. Disconnect the ECM connector.

  1. Turn the engine switch on (IG) position, and measure the voltage according to the value(s) in the table below when the shift lever is moved to each position.

    Voltage:
    Shift Position
    Tester Connection
    Specified Condition
    S, "+" and "-"
    A7 - 9 (S) - Body ground
    10 to 14 V
    Except S, "+" and "-"

    Below 1 V


    Lexus Gs430, Gs300. Uzs190 Grs190.A960E Automatic Transmission.Electronic Controlled Automatic Transmission System.Electronic Controlled Automatic Transmission System  Transmission Control Switch Circuit
  1. Turn the engine switch off position.

  1. Disconnect the ECM connector.

  1. Measure the resistance according to the value(s) in the table below when the shift lever is moved to each position.

    Resistance:
    Shift Position
    Tester Connection
    Specified Condition
    Press continuously
    "+"
    (Up shift)
    A7 - 30 (SFTU) - Body ground
    Below 1 Ω
    S

    10 kΩ or higher
    Press continuously
    "-"
    (Down shift)
    A7 - 19 (SFTD) - Body ground
    Below 1 Ω
    S

    10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE