P0868

DTC 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.




CONSULT-III Reference Value









On Board Diagnosis Logic
- This is not an OBD-II self-diagnostic item.
- Diagnostic trouble code "P0868 SEC/PRESS DOWN" with CONSULT-III is detected when secondary fluid pressure is too low compared with the commanded value while driving.




Possible Cause
- Harness or connectors
(Solenoid circuit is open or shorted.)
- Pressure control solenoid valve B (Secondary pressure solenoid valve) system
- Transmission fluid pressure sensor A (Secondary pressure sensor)
- Line pressure control system




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. 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)
3. Start engine and maintain the following conditions for at least 10 consecutive seconds.
VEHICLE SPEED (accelerate slowly): 0 to 50 km/h (31 MPH)
ACC PEDAL OPEN: 0.5/8 - 1.0/8
RANGE: "D" position
4. If DTC is detected, go to "Diagnosis Procedure".




Diagnosis Procedure
1.CHECK INPUT SIGNAL
With CONSULT-III
1. Start engine.
2. Select "MAIN SIGNALS" in "DATA MONITOR" mode for "TRANSMISSION" with CONSULT-III.
3. Start vehicle and read out the value of "SEC PRESS".





OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2.CHECK LINE PRESSURE
Perform line pressure test. Refer to Inspections Before Trouble Diagnosis.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts. Refer to Inspections Before Trouble Diagnosis.
3.DETECT MALFUNCTIONING ITEM
Check the following:
- Pressure control solenoid valve B (Secondary pressure solenoid valve). Refer to P0778.
- Pressure control solenoid valve A (Line pressure solenoid valve). Refer to P0745.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.
4.CHECK TRANSMISSION FLUID PRESSURE SENSOR A (SECONDARY PRESSURE SENSOR) SYSTEM
Check transmission fluid pressure sensor A (secondary pressure sensor) system. Refer to P0840.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.
5.DETECT MALFUNCTIONING ITEM
Check the following:
- Power supply and ground circuit for TCM. Refer to P1701.
- The TCM pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
6.CHECK DTC
Perform "DTC Confirmation Procedure".
OK or NG
OK >> INSPECTION END
NG >> Replace the transaxle assembly. Refer to .