Diagnosis - A/T: Description: Notes

The Viscous Converter Clutch (VCC) has a 3-element torque converter in addition to a converter clutch. The VCC is a self-contained fluid coupling built into a pressure plate with a friction facing. When engaged, the VCC is forced against the converter cover. Power is transmitted from friction face, through a fluid coupling, to transmission turbine shaft. The VCC fluid coupling uses viscous properties of silicone fluid, between closely spaced input and output faces, to transmit power.

VCC application will occur at various engine speeds, depending on throttle position, engine load, engine temperature, transmission temperature, ambient temperature and altitude. Applying the VCC eliminates converter slippage, resulting in improved fuel economy and reduced fluid operating temperatures. When VCC is disengaged, the assembly operates as a conventional torque converter.

Based upon various sensor input signals, the Powertrain Control Module (PCM) controls ground circuit to the VCC solenoid (located inside transmission). In order for VCC to engage, internal transmission fluid pressure must be correct, vehicle speed must be 26-50 MPH and engine must be at normal operating temperature.