P0841

Data List Reference TableDTC P0841: Abnormality in Line Pressure Sensor Function

DIAGNOSTIC FUNCTION
TCM conducts fault detection by comparing the secondary pressure sensor reading with the primary pressure sensor reading.

DESCRIPTIONS OF MONITOR METHODS
^ The pulley ratio range is from 0.5 to 1, and the relationship between the actual primary and secondary pressures shown as the pulley ratio is below 0.5 or above 1.

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)
^ Not applicable

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
^ Transmission range switch position: D.
^ Vehicle speed: 10 km/h (6.2 mph) or more.
^ Throttle position: 1/8 or more.
^ Engine speed: 450 r/min or more.
^ Transmission fluid temperature: 20°C (68°F) or more.
^ Transmission fluid temperature: 99°C (210°F) or less.
^ Voltage of battery: 9 volts or more.
^ Voltage of battery: 16 volts or less.
^ Transmission range switch: normal.
^ Secondary pulley speed sensor: normal.
^ Line pressure solenoid valve performance: normal.
^ Lock-up solenoid valve performance: normal.
^ Primary pulley speed sensor: normal.
^ Stepper motor: normal.
^ Lock-up solenoid valve: normal.
^ Line pressure solenoid valve: normal.
^ Throttle position sensor: normal.
^ Engine revolution: normal.
^ Secondary pressure solenoid valve: normal.
^ Secondary pressure solenoid valve performance: normal.
^ Lock-up selection solenoid valve performance: normal.
^ Primary pressure sensor: normal.
^ Secondary pressure sensor: normal.
^ Primary or secondary pressure sensor performance: normal.
^ Secondary pressure sensor performance: normal.

Judgement Criteria
^ Actual primary pressure [pulley ratio (primary pulley ratio/secondary pulley ratio): more than 0.5 and less than 1]: lower limit of primary pressure. (5 seconds)
^ Actual primary pressure [pulley ratio (primary pulley ratio/secondary pulley ratio): more than 0.5 and less than 1]: upper limit of primary pressure. (5 seconds)

OBD-II DRIVE CYCLE PATTERN
All the conditions below continue for 5 seconds.
^ Ratio: 0.5-1
^ Percentage of transmission ratio change during driving is 0.1 or less.

PROBABLE CAUSES
^ Abnormal line pressure
^ Abnormality in primary pressure sensor system
^ Abnormality in secondary pressure sensor system
^ 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. M.U.T.-III data list
^ Item 18: Primary pressure
^ Item 19: Secondary pressure

(Refer to Data List Reference Table.) Data List Reference Table

Q: Is the check result normal?
YES: Intermittent malfunction
NO: Go to Step 3.

STEP 3. Line pressure check
Carry out "hydraulic test". Component Tests and General Diagnostics

Q: Is the check result normal?
YES: Go to Step 4.
NO: Repair according to the hydraulic pressure test diagnosis table.

STEP 4. Symptom recheck after erasing diagnosis code

Q: Is the check result normal?
YES: Intermittent malfunction
NO: Replace TCM.