DTC Advanced Diagnostics: P2720
DTC P2720 : CVT Lock-Up Clutch Control Solenoid Valve Circuit Low
General Description
The CVT lock-up clutch control solenoid valve controls hydraulic pressure to the torque converter clutch. The CVT lock-up clutch control solenoid valve is controlled by duty cycle output. The spool in the CVT lock-up clutch control solenoid valve moves the valve according to the current, and produces hydraulic pressure in proportion to the current. The transmission control module (TCM) measures the current that passes through the CVT lock-up clutch control solenoid valve and uses feedback control to compensate for the difference between the measured current and the commanded one. The failure occurs by an open circuit or an intermittent open circuit. If the TCM internal driver IC detects its abnormal or the measured current is not equal to the duty cycle command, the TCM detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 1 second or more |
| DTC Type | Two drive cycles, MIL on, Shift position indicator blinks |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| 12 volt battery voltage [Battery Voltage] | 10.0 V | - |
[ ]: HDS Parameter
Malfunction Threshold
One of the conditions is met for at least 1 second:
- TCM internal driver IC detects its abnormal.
- The measured current for the TCM's command value is as specified here.
| Duty (%) | Current (A) | Failure mode |
|---|---|---|
| 56.5 - 90.2 | Less than 0.19 | Low Input |
| More than 90.2 | Less than 0.27 | Low Input |
Possible Cause
The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- CVT lock-up clutch control solenoid valve LCCLS line open (includes a loose or disconnected connector)
- CVT lock-up clutch control solenoid valve LCC- line open (includes a loose or disconnected connector)
- CVT lock-up clutch control solenoid valve internal circuit open
- TCM internal circuit failure
Confirmation Procedure
Operating Condition
Start the engine, and wait for at least 1 second.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the TCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on, the shift position indicator blinks, and a Confirmed DTC and the freeze data are stored.
Conditions for clearing the DTC
The shift position indicator comes off by turning the vehicle to the OFF (LOCK) mode. The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool clear command.