Circuit/System Description

The transmission fluid pressure (TFP) switch 4 is part of the control solenoid (w/body and TCM) valve assembly and has no seviceable parts. The TCM supplies 12 volts to the TFP switch 4 on the TFP switch 4 signal circuit. The TFP switch 4 has an internal case ground. TFP switch 4 is normally closed, Low. When oil pressure is present at the TFP switch 4, the switch is open, high. The normally low clutch pressure control (PC) solenoid 4 controls the transmission fluid to the 1-2-3-4 clutch. The TCM monitors the normally closed TFP switch 4 signal circuit to determine the 1-2-3-4 clutch status.