Pressure Switches (Hard-Wired)

The Low/Reverse, Overdrive and 2-4 pressure switches are all located in the Solenoid Pack Assembly. These switches indicate to the TCM if hydraulic problems occur in the clutch circuits. The pressure switches do not tell the TCM how much pressure is in the circuit, though they open at approximately 11 psi and close at approximately 23 psi. They simply indicate that pressure exists or does not exist. This information verifies that the solenoids are operating correctly and if hydraulic pressure is available to determine if a loss of pump prime has occurred or to engage 1st gear if the shift lever electrical signal is incorrect.