Continental V8-4.6L DOHC (1995)
Series Throttle Controller Module: Description and Operation
Series Throttle Controller
The Series Throttle Controller (STC) is a driver module used to operate the four phase Series Throttle Stepper Motor.
-
The STC module operates in open loop and functions strictly on PCM commands.
-
The STC module positions the stepper motor based on the PCM signal.
-
The PCM receives feedback on the position of the stepper motor from the TP-B Sensor. In the absence of a PCM signal across the Traction Assist
Pulse Width (TAPW) circuit to the STC controller, the Series Throttle is kept in the open position.
-
The STC module also protects against motor and harness shorts to ground. The motor is shut-off in the event of a short and the module will
recover when the short is corrected.
Traction Assist System - Series Throttle
The Traction Assist (TA) System utilizes two separate vehicle subsystems to control wheel slippage.
-
First, the anti-lock brake system is used to monitor wheel slippage and apply the brakes at low speeds as slip is detected.
-
Second, the EEC-V system attempts to reduce the axle torque with ignition spark control and intake air control. This particular system is referred
to as the Series Throttle Traction Assist (TA) System. The Series Throttle (TA) System consists of a second throttle body mounted directly in
series with the main throttle body, a Series Throttle Stepper Motor, a Throttle Position Sensor B (TP-B) specifically for traction assist, a Series
Throttle Controller (STC), Powertrain Control Module (PCM), and the entire ABS/TA brake subsystem.
