Page 55 - Hydra-matic 6 Speed RWD Technician's Guide (October 2005)

ELECTRICAL COMPONENTS

Line Pressure Control (PC) Solenoid:
The line pressure control (PC) solenoid is part of the
control solenoid (w/body and TCM) valve assembly
and is not serviced separately. The line PC solenoid is a
precision electronic pressure regulator that controls
transmission line pressure based on current flow through CONTROL COIL
its coil windings. The TCM varies current to the PRESSURE ASSEMBLY
normally-high line PC solenoid from approximately SUPPLY HOUSING
0.1 amp for maximum line pressure, to 1.0 amps for PRESSURE EXHAUST
minimum line pressure. As current flow is increased, (ACTUATOR
FEED LIMIT)
the magnetic field produced by the coil moves the
solenoid’s variable restriction further away from the
exhaust port. Opening the exhaust port decreases the
output fluid pressure regulated by the PC solenoid,
which ultimately decreases line pressure. As current
flow is decreased, the reduced magnetic field produced
by the coil moves the solenoid's variable restriction CLOSED END
closer to the exhaust port, increasing the output fluid FEATURE O-RING VARIABLE SPRING
pressure regulated by the PC solenoid valve, which RESTRICTION
ultimately increases line pressure. The TCM controls CONNECTOR
the line PC solenoid based on various inputs, including
throttle position, transmission fluid temperature and
gear state. NORMALLY-HIGH PRESSURE CONTROL SOLENOID

The current flow to the line PC solenoid is primarily
affected by throttle position (engine torque), and is
also inversely proportional to throttle position (engine
torque). In other words, as the throttle position (engine
torque) increases, the current flow is decreased by the
TCM, which increases the pressure output of the line
PC solenoid.
If the TCM detects a pressure control solenoid valve
electrical malfunction, a DTC will be activated.

PRESSURE REGULATOR VALVE 2A PCS LINE

CONV FD 3 LINE

2 LINE

DECREASE EX ACT FD LIM

ISOLATOR ACT FD LIM

PCS LINE
5
LINE
PRESSURE
CONTROL PCS LINE
SOLENOID
N.H.

46 Figure 42