P0725

DTC P0725: Malfunction of Engine Speed

DIAGNOSTIC FUNCTION

TCM detects malfunction of engine speed received from the ECM by comparing the primary pulley speed with the secondary pulley speed.

DESCRIPTIONS OF MONITOR METHODS

- Primary pulley speed of 1,000 r/min or more and with the engine speed of 450 r/min or less
- When the differences in rotation between the engine and the primary pulley, and between the engine and the secondary pulley are 1,000r/min or more during direct-coupled operating
- CAN communication error occurs between ECM and TCM.

MONITOR EXECUTION

- transmission range:D
- Throttle valve opening : 1/8 or more

MONITOR EXECUTION CONDITIONS (OTHER MONITOR AND SENSOR)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)

- P0705: Malfunction of transmission range switch
- P0715: Malfunction of primary pulley speed sensor
- P0741: Abnormality in lockup function
- P0746: Abnormality in hydraulic control system function
- P0841: Abnormality in line pressure sensor function
- P0868: Secondary pressure drop
- P1706: Malfunction of throttle signal
Sensor (The sensor below is determined to be normal)

- Transmission range switch
- Primary pulley speed sensor
- Accelerator pedal position sensor

LOGIC FLOW CHARTS (Monitor Sequence)





DTC SET CONDITIONS

Check Conditions

- Transmission range switch position: D.
- Throttle position sensor voltage: 1.37 volts or more.
- Primary pulley speed: 1,000 r/min or more.
- The absolute value of the Primary pulley speed - secondary pulley speed: 1,000 r/min or less.
- Voltage of battery: 9 volts or more.
- Voltage of battery: 16 volts or less.
Judgment Criteria

- Engine revolution [primary pulley speed: 1,000 r/min or more]: less than 450 r/min.
- The difference of engine speed and primary speed: more than 1,000 r/min. (5 seconds)
- The difference of engine speed and secondary speed: more than 1,000 r/min. (5 seconds)

OBD-II DRIVE CYCLE PATTERN

transmission range: D (Drive the vehicle for 10 seconds or more while the accelerator opening angle is 20% or more)

PROBABLE CAUSES

- Malfunction of the CAN bus
- Malfunction of the engine system
- Malfunction of TCM

DIAGNOSTIC PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics

Use M.U.T.-III to perform the CAN bus diagnosis.

Q. Is the check result normal?

YES Go to Step 2.
NO Go to "CAN Troubleshooting."
STEP 2. M.U.T.-III diagnosis code

Check if the engine-related diagnosis code is set.

Q. Is the check result normal?

YES Go to Step 3.
NO Go to "Engine Troubleshooting."
STEP 3. Symptom recheck after erasing diagnosis code

Q. Is the check result normal?

YES Intermittent malfunction
NO Replace TCM.