P0841

DTC P0841 PRESSURE SENSOR FUNCTION

Description
Using the engine load (throttle position), the primary pulley revolution speed, and the secondary pulley revolution speed as input signal, TCM changes the operating pressure of the primary pulley and the secondary pulley and changes the groove width of the pulley to control the gear ratio.

CONSULT-III Reference Value:

On Board Diagnosis Logic
- This is not an OBD-II self-diagnostic item.
- Diagnostic trouble code P0841 PRESS SEN/FNCTN with CONSULT-III is detected when correlation between the values of the secondary pressure sensor and the primary pressure sensor is out of specification.

Possible Cause
- Transmission fluid pressure sensor A (Secondary pressure sensor)
- Transmission fluid pressure sensor B (Primary pressure sensor)
- Harness or connectors
(Sensor circuit is open or shorted.)

DTC Confirmation Procedure

CAUTION: Always drive vehicle at a safe speed.

NOTE: If DTC Confirmation Procedure has been previously performed, always turn ignition switch OFF and wait at least 10 seconds before performing the next test.

After the repair, perform the following procedure to confirm the malfunction is eliminated.

WITH CONSULT-III
1. Turn ignition switch ON and select DATA MONITOR mode for TRANSMISSION with CONSULT-III.
2. Start engine and maintain the following conditions for at least 12 consecutive seconds.
VEHICLE SPEED: 40 km/h (25 MPH) More than
RANGE: D position
3. If DTC is detected, go to CVT-126, "Diagnostic Procedure".

Diagnostic Procedure
1. CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis. Refer to CVT-54, "SELF-DIAGNOSTIC RESULT MODE". With Manufacturer's Scan Tool
Is any malfunction of the U1000 CAN COMM CIRCUIT indicated?
YES >> Check CAN communication line. Refer to CVT-60, "DTC U1000 CAN COMMUNICATION LINE". Transmission Control System
NO >> GO TO 2.

2. CHECK INPUT SIGNALS

With CONSULT-III
1. Start engine.
2. Select ECU INPUT SIGNALS in DATA MONITOR mode for TRANSMISSION with CONSULT-III.
3. Start vehicle and read out the value of SEC HYDR SEN and PRI HYDR SEN.





Without CONSULT-III
1. Start engine.
2. Check voltage between TCM connector terminals and ground.





OK or NG
OK >> GO TO 6.
NG >> GO TO 3.

3. CHECK LINE PRESSURE
Perform line pressure test. Refer to CVT-40, "LINE PRESSURE TEST". Line Pressure Test
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.

4. CHECK TRANSMISSION FLUID PRESSURE SENSOR A (SECONDARY PRESSURE SENSOR) SYSTEM AND TRANSMISSION FLUID PRESSURE SENSOR B (PRIMARY PRESSURE SENSOR) SYSTEM
Check transmission fluid pressure sensor A (secondary pressure sensor) system and transmission fluid pressure sensor B (primary pressure sensor) system. Refer to CVT-121, "DTC P0840 TRANSMISSION FLUID PRESSURE SENSOR A CIRCUIT (SEC PRESSURE SENSOR)". P0840
Refer to CVT-128, "DTC P0845 TRANSMISSION FLUID PRESSURE SENSOR B CIRCUIT (PRI PRESSURE SENSOR)". P0845
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.

5. DETECT MALFUNCTIONING ITEM
Check the following:
- Pressure control solenoid valve A (Line pressure solenoid valve). Refer to CVT-103, "Component Inspection". P0745
- Pressure control solenoid valve B (Secondary pressure solenoid valve). Refer to CVT-113, "Component Inspection". P0778
- Step motor. Refer to CVT-155, "Component Inspection". P1777
OK or NG6
OK >> GO TO 6.
NG >> Repair or replace damaged parts.

6. CHECK DTC
Perform CVT-125, "DTC Confirmation Procedure".
OK or NG
OK >> INSPECTION END
NG >> Replace TCM or transaxle assembly.