K 1500 Suburban 4WD V8-5.3L VIN Z Flex Fuel (2003)
Torque Converter Clutch Solenoid: Description and Operation
4L80-E/4L85-E
4L80-E/4L85-E
Torque Converter Clutch Solenoid Valve
The PCM energizes the torque converter clutch pulse width modulated (TCC PWM) solenoid valve, which is located on the transmission valve body.
The TCC PWM solenoid valve acts on the TCC apply valve in order to control the torque converter clutch application.
The TCC PWM solenoid valve is pulse width modulated by the PCM. This means that the PCM pulses the solenoid so that the hydraulic pressure against
the torque converter clutch modulates. This modulated pressure allows the TCC to slip slightly, thus keeping the TCC balanced just at the point of
engagement.
One diagnostic code is associated with the TCC PWM solenoid valve Code P1860, TCC solenoid circuit electrical, detects a fault in the TCC circuit.
While Code P1860 is set, both fourth gear in hot mode and the TCC are inhibited. Shift adapts do not update and the MIL illuminates. Recovery can
occur on the next ignition cycle.
