Lexus IS250 IS220d GSE20 ALE20 - A960E AUTOMATIC TRANSMISSION

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)

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

Automatic Transmission System - Transmission Control Switch Circuit. A960E AUTOMATIC TRANSMISSION. Lexus IS250 IS220d GSE20 ALE20

INSPECTION PROCEDURE

1.CHECK HARNESS AND CONNECTOR (BATTERY - TRANSMISSION CONTROL SWITCH)
Automatic Transmission System - Transmission Control Switch Circuit. A960E AUTOMATIC TRANSMISSION. Lexus IS250 IS220d GSE20 ALE20

Disconnect the transmission control switch connector of shift lock control unit assembly.

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

  • Standard voltage:
  • Switch ConditionTester ConnectionSpecified Condition
    Engine switch on (IG)3 - Body ground10 to 14 V
    Engine switch offBelow 1 V
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
2.CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - BODY GROUND)
Automatic Transmission System - Transmission Control Switch Circuit. A960E AUTOMATIC TRANSMISSION. Lexus IS250 IS220d GSE20 ALE20

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

  • Standard resistance:
  • Tester ConnectionSpecified Condition
    5 - Body groundBelow 1 Ω
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
3.INSPECT TRANSMISSION CONTROL SWITCH
Automatic Transmission System - Transmission Control Switch Circuit. A960E AUTOMATIC TRANSMISSION. Lexus IS250 IS220d GSE20 ALE20

Measure resistance between each terminal of shift lock control unit assembly when the shift lever is moved to each position.

  • Standard resistance:
  • Shift PositionTester ConnectionSpecified Condition
    S, "+" and "-"3 - 7Below 1 Ω
    Except S, "+" and "-"10 kΩ or higher
    Press continuously
    "+"
    (Up shift)
    2 - 5Below 1 Ω
    S10 kΩ or higher
    Press continuously
    "-"
    (Down shift)
    1 - 5Below 1 Ω
    S10 kΩ or higher
NG
REPLACE TRANSMISSION CONTROL SWITCH
OK
4.CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - ECM)
Automatic Transmission System - Transmission Control Switch Circuit. A960E AUTOMATIC TRANSMISSION. Lexus IS250 IS220d GSE20 ALE20

Connect the transmission control switch connector of shift lock control unit assembly.

Disconnect the ECM connector.

Turn the ignition 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.

  • Standard voltage:
  • Shift PositionTester ConnectionSpecified Condition
    S, "+" and "-"A6-9 (S) - Body ground10 to 14 V
    Except S, "+" and "-"Below 1 V
Automatic Transmission System - Transmission Control Switch Circuit. A960E AUTOMATIC TRANSMISSION. Lexus IS250 IS220d GSE20 ALE20

Turn the ignition switch off position.

Disconnect the ECM connector.

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

  • Standard resistance:
  • Shift PositionTester ConnectionSpecified Condition
    Press continuously
    "+"
    (Up shift)
    A6-30 (SFTU) - Body groundBelow 1 Ω
    S10 kΩ or higher
    Press continuously
    "-"
    (Down shift)
    A6-19 (SFTD) - Body groundBelow 1 Ω
    S10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE