Dtc Detection Condition And Trouble Area Reference

DTC No.

DTC Detection Condition

Trouble Area

P0781

Gear required by the ECM does not match the actual gear when driving. (2 trip detection logic)

• Valve body is blocked up or stuck (1-2 shift valve)

• Shift solenoid valve SLT remains open or closed

• Automatic transmission (clutch, brake or gear, etc.)

monitor description monitor description

This DTC indicates that the 1-2 shift valve in the valve body is locked in the direction that the spring compresses.

The ECM commands gear shifts by turning the shift solenoid valves ON/OFF and controls the oil pressure applied to the valves in the valve body.

The ECM calculates the actual transmission gear by comparing the signals from the input speed sensor (NT) and the output speed sensor (SP2). The ECM can detect mechanical problems in the shift solenoids, valve body and automatic transmission (clutch, brake, gear etc.). If the ECM detects that the actual gear position and the commanded gear position are different, it will illuminate the MIL and store the DTC.

monitor strategy

MONITOR STRATEGY REFERENCE

Related DTCs

P0781: Valve body/Rationality check

Required sensors/Components

Valve body, Automatic transmission assembly, Speed sensor (NT), Speed sensor (NO), Vehicle speed sensor, Throttle position sensor

Frequency of operation

Continuous

Duration

Condition (A) and (B): 0.4 seconds Condition (C): 3 seconds Condition (D): 0.5 seconds

MIL operation

2 driving cycles

Sequence of operation

None

typical enabling conditions typical enabling conditions

The following conditions are common to all conditions below: Condition (A), (B), (C) and (D) TYPICAL ENABLING CONDITIONS REFERENCE

The monitor will run whenever this DTC is not present. None

2006 TRANSMISSION A750F Automatic Transaxle - Sequoia

Turbine speed sensor (NT) circuit

Not circuit malfunction

Output speed sensor (NO) circuit

Not circuit malfunction

Shift solenoid valve S1 circuit

Not circuit malfunction

Shift solenoid valve S2 circuit

Not circuit malfunction

Shift solenoid valve SR circuit

Not circuit malfunction

Shift solenoid valve SL1 circuit

Not circuit malfunction

Shift solenoid valve SL2 circuit

Not circuit malfunction

ECT (Engine Coolant Temperature) sensor circuit

Not circuit malfunction

KCS sensor circuit

Not circuit malfunction

ETCS (Electric Throttle Control System)

Not system down

Transmission range

"D"

ECT

40°C (104°F) or more

Spark advance from Max. retard timing by KCS control

0° crankshaft angle or more

Engine

Starting

Transfer range

"HIGH"

Vehicle speed sensor circuit

Not circuit malfunction

Output shaft speed sensor circuit

Not circuit malfunction

Transfer output speed

143 rpm or more

NO/NOtf (Transfer input speed/Transfer output speed)

0.9 to 1.1

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