DTC P0840 Transmission Fluid Pressure Sensor/Switch "A" Circuit |
DTC P0842 Transmission Fluid Pressure Sensor/Switch "A" Circuit Low |
DTC P0843 Transmission Fluid Pressure Sensor/Switch "A" Circuit High |
| DTC No. | DTC Detection Condition
| Trouble Area |
| P0840 |
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| P0842 |
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| P0843 |
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| 1.READ VALUE USING INTELLIGENT TESTER (A/T OIL PRESSURE) |
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON.
Turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Data List.
In accordance with the display on the tester, read the Data List.
| Tester Display | Measurement Item/Range | Normal Condition | Diagnostic Note |
| A/T Oil Pressure | Secondary oil pressure value/ min.: -0.625 MPa max.: 9.575 MPa | Secondary oil pressure inspection (D position stall test) 3.78 to 5.89 MPa | - |
| Result | Proceed to |
| Data display is not within Normal Condition range | A |
| Data display is within Normal Condition range | B |
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| A | |
| 2.CHECK HARNESS AND CONNECTOR (OIL PRESSURE SENSOR - ECM) |
Disconnect the oil pressure sensor connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| B12-1 (E2) - B8-72 (EPTO) | Always | Below 1 Ω |
| B12-2 (PTO) - B8-73 (PTO) | Always | Below 1 Ω |
| B12-3 (VC) - B8-95 (VCPT) | Always | Below 1 Ω |
| B8-72 (EPTO) - Body ground | Always | 10 kΩ or higher |
| B8-73 (PTO) - Body ground | Always | 10 kΩ or higher |
| B8-95 (VCPT) - Body ground | Always | 10 kΩ or higher |
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| OK | |
| 3.INSPECT ECM (VCPT TERMINAL VOLTAGE) |
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Connect the ECM connector.
Turn the ignition switch to ON.
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Switch Condition | Specified Condition |
| B12-1 (E2) - B12-3 (VC) | Ignition switch ON | 4.5 to 5.5 V |
| *1 | Front view of wire harness connector: (to Oil Pressure Sensor) |
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| OK | |
| 4.REPLACE OIL PRESSURE SENSOR |
Replace the oil pressure sensor (Click here).
| NEXT | |
| 5.PERFORM INITIALIZATION |
Perform the initialization (Click here).
Check for DTCs again (Click here).
| NEXT | ||
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| 6.REPLACE ECM |
Replace the ECM (Click here).
| NEXT | |
| 7.PERFORM INITIALIZATION |
Perform the initialization (Click here).
Check for DTCs again (Click here).
| NEXT | ||
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