Nissan Altima 2007-2012 Service Manual: P0868 secondary pressure down
Description
The pressure control solenoid valve B (secondary pressure solenoid valve) regulates the secondary pressure to suit the driving condition in response to a signal sent from the TCM.
DTC Logic
DTC DETECTION LOGIC
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.
Then wait at least 10 seconds before performing the next test.
1.CHECK DTC DETECTION
1. Turn ignition switch ON.
2. Select “DATA MONITOR”.
3. Make sure that output voltage of CVT fluid temperature sensor is within the range below.
ATF TEMP SEN : 1.0 – 2.0 V
If out of range, drive the vehicle to decrease the voltage (warm up the fluid) or stop engine to increase the voltage (cool down the fluid)
4. Start engine and maintain the following conditions for at least 10 consecutive seconds.
Is “P0868 SEC/PRESS DOWN” detected? YES >> Go to TM-346, "Diagnosis Procedure".
NO >> Check intermittent incident. Refer to GI-42, "Intermittent Incident".
Diagnosis Procedure
1.CHECK LINE PRESSURE
Perform line pressure test. Refer to TM-423, "Inspection and Judgment".
Is the inspection result normal? YES >> GO TO 2.
NO >> Repair or replace damaged parts. Refer to TM-423, "Inspection and Judgment".
2.CHECK PRESSURE CONTROL SOLENOID VALVE B (SECONDARY PRESSURE SOLENOID VALVE)
1. Turn ignition switch OFF.
2. Disconnect CVT unit connector.
3. Check pressure control solenoid valve B (secondary pressure solenoid valve). Refer to TM-347, "Component Inspection [Pressure Control Solenoid Valve B (Secondary Pressure Solenoid Valve)]".
Is the inspection result normal? YES >> GO TO 3.
NO >> Replace transaxle assembly. Refer to TM-447, "Exploded View".
3.CHECK PRESSURE CONTROL SOLENOID VALVE A (LINE PRESSURE SOLENOID VALVE)
Check pressure control solenoid valve A (line pressure solenoid valve). Refer to TM-347, "Component Inspection [Pressure Control Solenoid Valve A (Line Pressure Solenoid Valve)]".
Is the inspection result normal? YES >> GO TO 4.
NO >> Replace transaxle assembly. Refer to TM-447, "Exploded View".
4.CHECK TRANSMISSION FLUID PRESSURE SENSOR A (SECONDARY PRESSURE SENSOR) SYSTEM
Check transmission fluid pressure sensor A (secondary pressure sensor) system. Refer to TM-341, "DTC Logic".
Is the inspection result normal? YES >> GO TO 5.
NO >> Repair or replace damaged parts.
5.DETECT MALFUNCTIONING ITEMS
Check TCM connector pin terminals for damage or loose connection with harness connector.
Is the inspection result normal? YES >> Replace TCM. Refer to TM-430, "Exploded View".
NO >> Repair or replace damaged parts.
Component Inspection [Pressure Control Solenoid Valve A (Line Pressure Solenoid Valve)]
1.CHECK PRESSURE CONTROL SOLENOID VALVE A (LINE PRESSURE SOLENOID VALVE)
Check resistance between CVT unit terminal 2 and ground.
Is the inspection result normal? YES >> INSPECTION END
NO >> Replace transaxle assembly. Refer to TM-447, "Exploded View".
Component Inspection [Pressure Control Solenoid Valve B (Secondary Pressure Solenoid Valve)]
1.CHECK PRESSURE CONTROL SOLENOID VALVE B (SECONDARY PRESSURE SOLENOID VALVE)
Check resistance between CVT unit terminal 3 and ground.
Is the inspection result normal? YES >> INSPECTION END
NO >> Replace transaxle assembly. Refer to TM-447, "Exploded View".
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 pri ...
P1701 transmission control module (power supply)
Description
When the power supply to the TCM is cut OFF, for example because the battery
is removed, and the self-diagnosis
memory function stops, malfunction is detected.
NOTE:
Since “P170 ...
Other materials:
Side guard molding
Removal and Installation
1. Double-faced adhesive tape
Removal
CAUTION:
Never apply tack-paper adhesive remover to body panel surface finished with
lacquer-based paints.
• Original side guard molding is affixed to body panel with double-faced
adhesive tape.
1. Heat molding to betwe ...
Turn signal and hazard warning
lamps
System Diagram
System Description
• BCM (Body Control Module) controls turn signal lamp (RH and LH) and hazard
warning lamp operation.
• Combination meter operates turn (RH and LH) indicator according to CAN
communication signals from
BCM.
Component Parts Location
1. BCM M16, M ...
Before starting the engine
● Make sure the area around the vehicle is
clear.
● Check fluid levels such as engine oil, coolant,
brake fluid, and windshield-washer fluid
as frequently as possible, or at least whenever
you refuel.
● Check that all windows and lights are clean.
● Visually inspect ti ...