Diesel PCM Outputs
DIESEL PCM OUTPUTS
Electronic Air Filter Minder
Air Filter Minder Indicator:
F-250/550 and Excursion vehicles are equipped with an Electronic Air Filter Minder sensor located in the air cleaner end cover. The sensor is wired to the instrument cluster from the sensor. When the restriction in the air inlet system reaches an amount that indicates restriction, the switch will close and a filter restriction indicator will illuminate.
Passive Anti-Theft System
The Excursion is equipped with a passive anti-theft system (PATS) which prevents engine operation without the correctly encoded ignition key. For detailed information on the operation of this system, refer to Antitheft and Alarm Systems.
Electronic Variable Geometry Turbocharger (VGT) Control Valve
Electronic Variable Geometry Turbocharger (VGT) Control Valve:
The Electronic Variable Geometry Turbocharger (VGT) Control Valve is a four-way proportional hydraulic flow control valve with closed center position. The valve controls linear actuator position of a closed loop hydraulic servo by charging and venting flow on both sides of a piston. Linear displacement feedback from the actuator varies a feedback spring force to move the valve spool to the center closed position when the actuator reaches the desired position. Therefore, actuator position is dependent only on control valve current - it is independent of hydraulic fluid temperature and viscosity. The PCM characterizes the VGT/turbocharger at idle with the engine at normal operating temperature. It is possible to force a learn sequence by clearing the DTC's and allowing the engine to idle for 5 minutes at normal temperature. Audible noise is possible during the learn cycle.
Exhaust Gas Recirculation Valve Control and Valve Position Sensor
Exhaust Gas Recirculation Valve Control And Valve Position Sensor:
The Exhaust Gas Recirculation Valve Control controls the amount of exhaust gases recirculated back to the intake. It is a proportional solenoid with a built-in position sensor. The Valve Position Sensor is needed to give the control circuit feedback to achieve desired travel position. The Exhaust Gas Recirculation Valve Position Sensor is a variable resistance pintle position sensor that makes position measurements of the exhaust gas recirculation valve control actuator. Input signals from the manifold absolute pressure (MAP) and barometric pressure (BARO) sensors are used by the PCM to calculate and control the EGR system flow.
Fuel Injection Control Module
Fuel Injection Control Module (FICM):
The Fuel Injection Control Module (FICM) receives information from the PCM, including volume of fuel desired, rpm, engine oil temperature, injection control pressure and others. The FICM then uses those signals to calculate fuel injection and duration. After calculating injector fuel delivery time, the FICM sends 48 volts at 20-amp pulse to the correct injector so that the correct amount of fuel is delivered to the cylinder at the correct time.
Glow Plug Control Module
Glow Plug Control Module:
The Glow Plug system is composed of solid state Glow Plug Control Module (GPCM), glow plugs and the associated wiring harness. The glow plug on-time is controlled by the Powertrain Control Module (PCM) and is a function of oil temperature, barometric pressure and battery voltage. The PCM enables the GPCM which drives the individual glow plugs. Glow plug on-time normally varies between 1 to 120 seconds. In addition to PCM control, the GPCM internally limits the glow plug operation to 180 seconds regardless of PCM commanded on-time. The power to the glow plugs is provided through the GPCM solid state drivers directly from the vehicle battery. The GPCM monitors and detects individual glow plug functionality, and the control and communication links to the PCM. The failures detected by the GPCM are passed to the PCM using a serial communication signal on the diagnostic line.
NOTE: Wait-to-start lamp on-time is controlled by the PCM and is independent from GPCM on-time.
Glow Plug Indicator Lamp
Glow Plug Indicator:
The Glow Plug Indicator Lamp (GPIL) is located in the instrument cluster and is used to prompt the operator when the engine is ready to be cranked and started. When the light goes out, the vehicle is ready to start. As a bulb check, the light is commanded on at every key cycle even though the glow plug system may not be required. On-time normally varies between 1 and 10 seconds. Wait-to-Start indication is independent of glow plug relay on-time as the glow plug system can stay on after the indicator goes off.
The indicator is controlled by the instrument cluster, based on electronic information from the PCM. The PCM sends an electronic signal command, via Standard Corporate Protocol (SCP) communications, to the cluster on how long to keep the indicator on. The instrument cluster performs diagnostics for the GPIL circuit.
Injection Pressure Regulator
Injection Pressure Regulator:
The Injection Pressure Regulator controls injection oil pressure. An electrical signal to a solenoid creates a magnetic field which applies a variable force on a valve servo to control pressure. The quantity of fuel delivered to the combustion chamber is proportional to injection control pressure.
An open circuit will result in minimum oil pressure and a no-start situation. A short to ground in a circuit results in maximum oil pressure, and is limited by a mechanical pop-off valve to 27,580 kPa (4000 psi).
Speed Control Indicator
Speed Control Indicator:
An indicator light in the instrument cluster will illuminate when the speed control is engaged. The PCM turns the indicator on by providing a ground path.
Tachometer
Tachometer:
The Tachometer is controlled by the instrument cluster. The cluster receives electronic information, via SCP communications, from the PCM for the RPM of the engine. The electronic signal is a buffered representation of the Camshaft Position Sensor (CMP) signal.
An open or short circuit of the tachometer output wiring will result in an inoperative tachometer.
Vistronic Drive Fan (VDF)
The cooling fan electronic clutch is controlled by the PCM. The PCM monitors Engine Oil Temperature (EOT) and Engine Coolant Temperature (ECT) and sends a duty cycle command to the fan clutch to achieve adequate cooling. When a circuit fault is detected the PCM will set a DTC.
Water in Fuel Indicator
Water In Fuel Injector:
The Water in Fuel Indicator is controlled by the instrument cluster. The cluster receives electronic information, via Standard Corporate Protocol (SCP) communications, from the PCM for water in fuel status. If the water in fuel sensor indicates that there is water in the fuel separator/housing (located within the fuel condition module), the PCM sends an SCP message to the cluster to illuminate the water in fuel indicator.