The Automatic Transmission changes the gear position of the transmission utilizing a combination of Clutches and Brakes, which are controlled by solenoid valves. The New Alpha Automatic Transmission consists of a: LR (Low and Reverse Brake), KD (Kick Down Brake), FC (Front Clutch), RC (Rear Clutch), and EC (End Clutch). The gear position is determined by the combination of 3 kinds of Shift Control Solenoid Valves. ( SCSV A , SCSV B, SCSV C )
The PCM/TCM checks the Shift Control Solenoin Valve A control 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 TCM judges that SCSV A control solenoid circuit is malfunctioning and sets this code.
Item | Detecting Condition | Possible Cause |
DTC Strategy | ● Check voltage range | ● Open or short in circuit ● Faulty SCSV-A ● Faulty PCM/TCM |
Enable Conditions | ● 25% < Solenoid duty < 100% ● Timer of PWM monitoring > 0.5sec ● 8V < Voltage of Battery <16V | |
Threshold Value | ||
Diagnostic Time | ● More than 300 ms | |
Fail Safe | ● Locked in 3 rd gear. |