Torque Converter Clutch (TCC)
TCC Hydraulic Circuits
| 1 | Inspect the pump to transmission case hydraulic passages and seals. |
|---|---|
| 2 | Inspect the transmission case to main control hydraulic passages. |
| 3 | Inspect the main control hydraulic passages. |
Torque Converter Clutch (TCC) and Lubrication Circuits TCC Released
Pressure for TCC release is supplied by the main pressure regulator valve to the TCC control valve through the CONV FD circuit. The CONV FD circuit also supplies lubrication for the differential. When the TCC is released, the TCC control valve is positioned by the TCC solenoid to direct CONV FD pressure to the TCC RELEASE circuit to release the TCC. TCC RELEASE pressure returns to the TCC control valve through the TCC APPLY circuit. The position of the TCC control valve opens the TCC APPLY circuit to the COOLER FD circuit which allows the transmission fluid returned from the torque converter to cycle through the thermal bypass valve circuit when the TFT is below 80 deg.C-93 deg.C (176 deg.F-200 deg.F) or the transmission fluid cooler when the temperature is above 80 deg.C-93 deg.C (176 deg.F-200 deg.F).
Return transmission fluid from the thermal bypass valve or the transmission fluid cooler supplies transmission lubrication through the LUBE circuit which runs through the input shaft.
The position of the TCC control valve is controlled by pressure from the TCC solenoid through the VBS TCC circuit. The TCC solenoid is controlled by the PCM.
Torque Converter Clutch (TCC) and Lubrication Circuits TCC Applied
When the TCC clutch is applied, the TCC solenoid applies pressure to the TCC control and regulator valves to position the valves to apply the TCC clutch. Regulated line pressure is supplied to the TCC control valve through the REG APPLY circuit by the TCC regulator valve. The TCC control valve directs the regulated line pressure from the REG APPLY circuit to the TCC APPLY circuit to apply the TCC. The v control valve blocks the TCC RELEASE circuit to maintain pressure in the TCC APPLY circuit. The TCC control valve directs the CONV FD circuit to the COOLER FD circuit to allow the transmission fluid to flow through the thermal bypass valve or the transmission fluid cooler to the LUBE circuit to lubricate the transmission.