Torque Converter Clutch Solenoid Valve

WARNING: This page is about a different car, the 2002 GMC Yukon XL, 2002 GMC Sierra, 2002 Chevrolet Suburban, and 2002 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

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 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. DTC P1860 sets when an electrical fault is detected in the TCC circuit. While DTC P1860 is set, both 4th gear in hot mode and the TCC are inhibited. Shift adapts do not update and the Malfunction Indicator Light (MIL) illuminates. Recovery can occur on the next ignition cycle.