The Automatic Transmission changes the gear position of the transmission utilizing a combination of Clutches and Brakes, which are controlled by solenoid valves. This Automatic Transmission consists of a: LR ( Low and Reverse Brake ), 2-4( 2-4 Brake ), UD ( Under Drive Clutch ), OD ( Over Drive Clutch ), REV ( Reverse Clutch ).
The PCM/TCM checks the Over Drive Clutch Control/Low & Reverse Brake Signal by monitoring the feedback signal from the solenoid valve drive circuit. If an unexpected signal is monitored (for example, high voltage is detected when low voltage is expected, or low voltage is detected when high voltage is expected), the PCM/TCM judges that Under Drive Clutch contorl solenoid circuit is malfunctioning and sets this code.
Item | Detecting Condition | Possible Cause | |
Case 1 | DTC Strategy |
•
Electrical Check |
•
Open or short in circuit
•
Faulty OD/LR SOLENOID VALVE
•
Faulty PCM/TCM |
Enable Conditions |
•
PWM DUTY > 25% | ||
Threshold Value |
•
Comparision solenoid operation time with Feed back signal.(Solenoid ON and Short circuit) | ||
Case 2 | DTC Strategy |
•
- | |
Enable Conditions |
•
Comparision solenoid operation time with Feed back signal.(Solenoid OFF and Short circuit) | ||
Diagnostic Time |
•
More than 1sec. | ||
Fail Safe |
•
Locked in 3 rd gear. | ||
Solenoid Valve for Pressure Control
Sensor type : Normal open 3-way
Operating temperature : -30℃∼130℃
Voltage/Current : 5V, 1.2 A Max.
Internal resistance : 3.5 ± 0.2 Ω(25℃)
Fig 1) Wave form of "OD/LR(SCSV-A)" in 2nd gear
