Home Drivetrain Automatic Transmission/Transaxle AB60F AUTOMATIC TRANSMISSION / TRANSAXLE: AUTOMATIC TRANSMISSION SYSTEM
Last Modified: 11-27-2007 1.6 J
Service Category: Drivetrain Section: Automatic Transmission/Transaxle
Model Year: 2008 Model: LX570 Doc ID: RM000000YTG01RX
Title: AB60F AUTOMATIC TRANSMISSION / TRANSAXLE: AUTOMATIC TRANSMISSION SYSTEM: DESCRIPTION (2008 LX570)

Pattern Select Switch 2nd Start Mode Circuit

DESCRIPTION

When 2nd mode is selected with the No. 1 pattern select switch assembly, the ECM controls the shift solenoid valves and the transmission starts from 2nd gear.

The 2nd mode is the system that operates the throttle motor to control engine output to reduce skidding of the driving wheels, and guarantee takeoff acceleration, driving straightness and turning stability.

When the shift lever is in D, the transmission automatically shifts up through 3rd to 6th as usual.

WIRING DIAGRAM

Refer to Pattern Select Switch Power Mode Circuit AB60F AUTOMATIC TRANSMISSION / TRANSAXLE: AUTOMATIC TRANSMISSION SYSTEM: DESCRIPTION (2008 LX570)+ .

INSPECTION PROCEDURE

When the pattern select switch (2ND) is pushed, switch contact is made and 2nd mode is selected. To cancel 2nd mode, push the pattern select switch (2ND) once again.

HINT:

2nd mode is automatically canceled when the engine switch is turned off.

PROCEDURE

1.

DRIVING TEST

HINT:

The driving test should be performed on a paved road (nonskid road).

(a) Start the engine.

(b) Turn the 2ND switch off (normal drive mode).

(c) Confirm vehicle response by driving from a parked position to fully depressing the accelerator pedal.

(d) Turn the 2ND switch on and perform the same check as above.

When driving the vehicle with the 2ND switch on and off, check that there is a difference in acceleration.

OK:

There is a difference in acceleration.

OK

3.

INSPECT NO. 1 PATTERN SELECT SWITCH ASSEMBLY (2ND)


(a) Remove the No. 1 pattern select switch assembly AB60F AUTOMATIC TRANSMISSION / TRANSAXLE: PATTERN SELECT SWITCH: REMOVAL (2008 LX570) .

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

2 (2ND) - 3 (E)

Pattern select switch (2ND) and held pressed

Below 1 Ω

2 (2ND) - 3 (E)

Pattern select switch (2ND) released

10 kΩ or higher

OK

4.

CHECK HARNESS AND CONNECTOR (NO. 1 PATTERN SELECT SWITCH ASSEMBLY - BODY GROUND)


(a) Disconnect the V5 No. 1 pattern select switch assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

V5-3 (E) - Body ground

Always

Below 1 Ω

OK

5.

CHECK HARNESS AND CONNECTOR (NO. 1 PATTERN SELECT SWITCH ASSEMBLY - ECM)



(a) Disconnect the A38 ECM connector.

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

A38-4 (SNWI) - Body ground

Pattern select switch (2ND) pressed and held

Below 1 Ω

A38-4 (SNWI) - Body ground

Pattern select switch (2ND) released

10 kΩ or higher

OK