CONTINUOUSLY VARIABLE TRANSAXLE SYSTEM, Diagnostic DTC:P0842, P0843

DTC Code	DTC Name
P0842	Transmission Fluid Pressure Sensor/Switch "A" Circuit Low
P0843	Transmission Fluid Pressure Sensor/Switch "A" Circuit High

DESCRIPTION

The ECM performs learning control for the belt clamping pressure based on the belt clamping pressure signal, which is output by the oil pressure sensor.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory
P0842	Transmission Fluid Pressure Sensor/Switch "A" Circuit Low	When 2 seconds or more have elapsed after engine start, there is a short in the oil pressure sensor circuit for 0.5 seconds (1 trip detection logic).	Wire harness or connector Oil pressure sensor ECM	Comes on	DTC stored
P0843	Transmission Fluid Pressure Sensor/Switch "A" Circuit High	When 2 seconds or more have elapsed after engine start, there is an open or a short to +B in the oil pressure sensor circuit for 0.5 seconds (1 trip detection logic).	Wire harness or connector Oil pressure sensor ECM	Comes on	DTC stored

MONITOR DESCRIPTION

These DTCs indicate an open or short in the oil pressure sensor circuit. If there is an open or short in the oil pressure sensor circuit, the ECM detects the malfunction, illuminates the MIL and stores a DTC.

WIRING DIAGRAM


*a	Oil Pressure Sensor

CAUTION / NOTICE / HINT

CAUTION:

Do not perform a stall test if there are any people or objects near the vehicle.
The vehicle could begin moving suddenly, resulting in a serious accident.

Do not perform a stall test if any wheel chocks are out of position.
The vehicle could begin moving suddenly, resulting in a serious accident.

Do not perform the stall test on a slippery or low-friction surface that could allow the tires to spin.
The vehicle could begin moving suddenly, resulting in a serious accident.

Note

Perform initialization after replacing any parts related to the continuously variable transaxle system.

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Check that no DTCs are stored after performing initialization.

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Tech Tips

After performing repair, clear the DTCs and perform the following procedure to check that DTCs are not output.

Start the engine and wait for 2 seconds or more.
Check for DTCs again.

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PROCEDURE

READ VALUE USING GTS (A/T OIL PRESSURE)

CAUTION:

Do not perform a stall test if there are any people or objects near the vehicle.
Do not perform a stall test if any wheel chocks are out of position.
Do not perform the stall test on a slippery or low-friction surface that could allow the tires to spin.

Note

This test must be conducted after checking and confirming that the engine is operating normally.
Perform this test while the CVT fluid temperature is between 50 and 100°C (122 and 212°F).
Perform this test with the A/C off.
Do not perform the stall speed test for longer than 5 seconds.

Warm up the engine.
Fully apply the parking brake and chock all 4 wheels.
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Connect the TC and TE1.

Powertrain > Engine and ECT > Active Test

Tester Display

Connect the TC and TE1
Enter the following menus: Powertrain / Engine and ECT / Data List / Primary.

Powertrain > Engine and ECT > Data List

Tester Display

A/T Oil Pressure

Tester Display
Connect the TC and TE1

Tester Display
A/T Oil Pressure

In accordance with the display on the GTS, read the Data List.

Powertrain > Engine and ECT > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
A/T Oil Pressure	Secondary oil pressure value	Min.: -64 MPa Max.: 63.998 MPa	Secondary oil pressure inspection: 3.9 to 4.7 MPa (39.8 to 47.9 kgf/cm², 566 to 682 psi): D position stall speed test 3.7 to 4.9 MPa (37.7 to 50.0 kgf/cm², 537 to 711 psi): R position stall speed test	-

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

A/T Oil Pressure

Secondary oil pressure value

Min.: -64 MPa

Max.: 63.998 MPa

Secondary oil pressure inspection:

3.9 to 4.7 MPa (39.8 to 47.9 kgf/cm², 566 to 682 psi): D position stall speed test
3.7 to 4.9 MPa (37.7 to 50.0 kgf/cm², 537 to 711 psi): R position stall speed test

Result

Result	Proceed to
Data display is not within Normal Condition range	A
Data display is within Normal Condition range	B

REPLACE ECM Click here

CHECK HARNESS AND CONNECTOR (OIL PRESSURE SENSOR - ECM)

Disconnect the C44 oil pressure sensor connector.
Disconnect the C63 ECM connector.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
C44-1 (E2) - C63-109 (EPTO)	Always	Below 1 Ω
C44-2 (PTO) - C63-79 (PTO)	Always	Below 1 Ω
C44-3 (VC) - C63-110 (VCPT)	Always	Below 1 Ω
C44-1 (E2) or C63-109 (EPTO) - Body ground and other terminals	Always	10 kΩ or higher
C44-2 (PTO) or C63-79 (PTO) - Body ground and other terminals	Always	10 kΩ or higher
C44-3 (VC) or C63-110 (VCPT) - Body ground and other terminals	Always	10 kΩ or higher

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

Standard Voltage

Tester Connection	Switch Condition	Specified Condition
C63-79 (PTO) - Body ground	Ignition switch ON	Below 1 V
C44-2 (PTO) - Body ground	Ignition switch ON	Below 1 V

Result

Proceed to
OK
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (OIL PRESSURE SENSOR - ECM)

CHECK ECM (VCPT TERMINAL VOLTAGE)

*a
Front view of wire harness connector

(to Oil Pressure Sensor)

Disconnect the oil pressure sensor connector.

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

Standard Voltage

Tester Connection	Switch Condition	Specified Condition
C44-3 (VC) - C44-1 (E2)	Ignition switch ON	4.75 to 5.25 V

Result

Proceed to
OK
NG

REPLACE ECM Click here

REPLACE OIL PRESSURE SENSOR

Replace the oil pressure sensor.

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Result

Proceed to
NEXT

PERFORM INITIALIZATION Click here

REPLACE ECM

Replace the ECM.

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Result

Proceed to
NEXT

PERFORM INITIALIZATION Click here

REPLACE ECM

Replace the ECM.

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Result

Proceed to
NEXT

PERFORM INITIALIZATION Click here