Lexus SC300 / Lexus SC400. Manual - part 82

OK

NG

2

Check harness and connector between battery and No. 4 solenoid valve, No. 4 solenoid valve
and ECM (See page IN–33).

Repair or replace harness or connector.

Proceed to next circuit inspection shown on ma-
trix chart (See page AT–66). However, when diag.
trouble code 46 is display, check and replace ECM.

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A304E (1UZ–FE) AUTOMATIC TRANSMISSION

TROUBLESHOOTING

AT–85

DTC

61

No.2 Vehicle Speed Sensor Circuit

CIRCUIT DESCRIPTION

The No.2 speed sensor detects the rotation speed of the transmission output shaft and sends signals to the
ECM. The ECM determines the vehicle speed based on the these signals. An AC voltage is generated in the
No.2 vehicle speed sensor coil as the rotor mounted on the output shaft rotates, and this voltage is sent to the
ECM.
The gear shift point and lock–up timing are controlled by the ECM based on the signals from this vehicle speed
sensor and the throttle position sensor signal.
If the No.2 vehicle speed sensor malfunctions, the ECM uses input signals from the No.1 vehicle speed sensor
as a back–up signal.

DTC No.

DTC Detecting Condition

Trouble Area

61

All conditions below are detected 500 times or more

continuously.

2 trip detection logic*

(a) No No.2 vehicle speed sensor signal in 4 No.1 ve-

hicle speed sensor signal pulses.

(b) Vehicle speed:

5.6 MPH (9 km/h) or more for

at least 4 secs.

(c) Park/neutral position switch:

OFF (Other than P or N position)

 No. 2 vehicle speed sensor

 Harness or connector between No.2 vehicle

speed sensor and ECM.

 ECM

*: See page AT–62

Reference

Waveform between terminals SP2+ and SP2– when vehicle speed is approx. 37 MPH (60km/h).

AT–86

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A304E (1UZ–FE) AUTOMATIC TRANSMISSION

TROUBLESHOOTING

IN–33

AT–66

WIRING DIAGRAM

DIAGNOSTIC CHART

DIAGNOSTIC CHART

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A304E (1UZ–FE) AUTOMATIC TRANSMISSION

TROUBLESHOOTING

AT–87

NG

OK

OK

NG

INSPECTION PROCEDURE

1

Check resistance between terminals SP2

+ 

and SP

–

 of ECM connector.

C

OK

P

Connect the check A to the ECM. (See EG section).

Check resistance between terminals SP

+

 and SP2

–

 of

ECM connector.

Resistance:

560 – 680 

Proceed to next circuit inspection shown on matrix chart
(See page AT–66).

2

Check No.2 vehicle speed sensor.

C

OK

Hint

P

OK

C

Remove No.2 vehicle speed sensor from transmission.
(See page AT–17).

Measure resistance between terminals 1 and 2 of speed
sensor.

Resistance:

560 – 680 

Reference

Check the vehicle speed sensor’s function

Check voltage between terminals 1 and 2 of the vehicle
speed sensor when a magnet is put close to the front
end of the vehicle speed sensor then taken away quick-
ly.

Voltage is generated intermittently.

The voltage generated is extremely low.

Replace No.2 vehicle speed sensor.

Check and repair harness and connector between
ECM and No.2 vehicle speed sensor (See page
IN–33).

AT–88

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A304E (1UZ–FE) AUTOMATIC TRANSMISSION

TROUBLESHOOTING