Ford 2003 Mustang Workshop Manual page 2298

Ignition Coil — Coil On Plug
The engine uses eight separate coil per plug units. Each coil per plug unit is controlled by the
powertrain control module (PCM).
Each coil per plug unit is mounted directly above each spark plug and activates its own spark plug in
the correct sequence as controlled by the PCM.
Refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual for additional information on the
ignition system.
Intake Air Temperature (IAT) Sensor
The intake air temperature (IAT) sensor provides the sequential fuel injection (SFI) system mixture
temperature information. The IAT sensor is used both as a density corrector for air flow calculation and
to proportion cold enrichment fuel flow. The IAT sensor is installed in the air cleaner inlet tube. The IAT
sensor is also used in determining EPC pressures.
Mass Air Flow (MAF) Sensor
The mass air flow (MAF) sensor measures the mass of air flowing into the engine. The MAF sensor
output signal is used by the powertrain control module to calculate injector pulse width. For
transmission strategies, the mass air flow sensor is used to regulate EPC, shift and torque converter
clutch scheduling.
Transmission Control Switch (TCS) and Transmission Control Indicator Lamp (TCIL)
The transmission control switch (TCS) is a momentary contact switch. When the switch is pressed, a
signal is sent to the PCM to allow automatic shifts from first through fourth gears or first through third
gears only. The PCM energizes the transmission control indicator lamp (TCIL) when the switch is off.
The TCIL indicates overdrive cancel mode activated (lamp on). When the TCIL is flashing, it indicates
electronic pressure control (EPC) circuit shorted or a monitored sensor failure.
Throttle Position (TP) Sensor
The throttle position (TP) sensor is a potentiometer mounted on the throttle body. The TP sensor
detects the position of the throttle plate and sends this information to the PCM. The TP sensor is used
for shift scheduling, electronic pressure control (EPC) and TCC control.
Digital Transmission Range (TR) Sensor
The digital transmission range (TR) sensor is located on the outside of the transmission at the manual
lever. The digital sensor completes the start circuit in PARK and NEUTRAL, and the back-up lamp
circuit in REVERSE. The digital sensor also opens/closes a set of four switches that are monitored by
the PCM to determine the position of the manual lever (P, R, N, D, 2, 1).
Output Shaft Speed (OSS) Sensor
The output shaft speed (OSS) sensor is a magnetic pickup, located at the output shaft ring gear, that
sends a signal to the powertrain control module (PCM) to indicate transmission output shaft speed.
The OSS sensor is used for torque converter clutch (TCC) control, shift scheduling and to determine
electronic pressure control (EPC).
Electronic Pressure Control (EPC) Solenoid
The EPC solenoid regulates transmission pressure. EPC valve pressure is used to control line
pressure.
Torque Converter Clutch (TCC) Solenoid