P0868

DTC P0868: Secondary Pressure Drop

SECONDARY PRESSURE SENSOR

SYSTEM CIRCUIT
Refer to DTC P0840. P0840

DIAGNOSTIC FUNCTION
TCM detects the secondary pressure drop during driving.

DESCRIPTIONS OF MONITOR METHODS
^ The value obtained by subtracting the actual secondary pressure sensor reading from the target secondary pressure sensor reading is 0.25 MPa (36 psi) or more.

MONITOR EXECUTION
^ Continuous

MONITOR EXECUTION CONDITIONS (OTHER MONITOR AND SENSOR)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)
^ P0741: Abnormality in lockup function
^ P0746: Abnormality in hydraulic control system function
^ P0841: Abnormality in line pressure sensor function

Sensor (The sensor below is determined to be normal)
^ Not applicable

LOGIC FLOW CHARTS (Monitor Sequence)

Logic Flow Charts (Monitor Sequence):

DTC SET CONDITIONS

Check Conditions
^ Engine speed: 450 r/min or more.
^ Voltage of battery: 9 volts or more.
^ Voltage of battery: 16 volts or less.
^ Secondary pulley speed sensor: normal.
^ Primary pulley speed sensor: normal.
^ Stepper motor: normal.
^ Line pressure solenoid valve: normal.
^ Secondary pressure solenoid valve: normal.
^ CAN communication status: normal.
^ Primary pressure sensor: normal.
^ Secondary pressure sensor: normal.
^ Primary or secondary pressure sensor performance: normal.
^ Secondary pressure sensor performance: normal.

Judgement Criteria
^ Secondary linear solenoid performance fail [target secondary pressure-measured secondary pressure: 0.25 MPa (36 psi) or more. (1.52 seconds)]: 2 count or more.

OBD-II DRIVE CYCLE PATTERN
All the conditions below continue for 3 seconds.
^ When the secondary pressure drops, torque down is permitted.
^ The secondary pressure drop judgement is possible.

PROBABLE CAUSES
^ Damaged wiring harness and connectors
^ Malfunction of CVT assembly
^ Malfunction of TCM

DIAGNOSTIC PROCEDURE

STEP 1. Check other diagnosis codes.

Q: Are other diagnosis codes set?
YES: Go to the appropriate troubleshooting.
NO: Go to Step 2.

STEP 2. Check the following connector:
^ B-08 CVT assembly connector
^ C-40 TCM connector
^ A-09 Intermediate connector

Check contacts for internal short circuit.

Q: Is the check result normal?
YES: Go to Step 3.
NO: Repair the defective connector.

STEP 3. Check for short to ground in the wiring harness between the TCM connector and the CVT assembly connector.
^ Between C-40 TCM connector (terminal No.39) and B-08 CVT assembly connector (terminal No.7)

OK: 100 Ohms or more

Q: Is the check result normal?
YES: Go to Step 4.
NO: Repair the wiring harness.

STEP 4. Symptom recheck after erasing diagnosis code

Q: Is the check result normal?
YES: Intermittent malfunction
NO: Replace the TCM, and then go to Step 5.

STEP 5. Retest the system.

Q: Is the check result normal?
YES: The inspection is complete.
NO: Replace the CVT assembly.