Diesel Engine Management System
Accelerator Pedal Position (APP) Sensor
As the accelerator pedal position changes, the sensor varies the signal voltage to the ECM.
Air Conditioning (A/C) Compressor Clutch Relay
When the engine control module (ECM) receives a demand for cooling from the A/C system, it delays the compressor from being energized, and enriches the mixture to assure smooth transition to the A/C mode.
Alternator Control
The alternator signals the ECM during charging.
Barometric Pressure (BARO) Sensor
The BARO sensor is inside the ECM. It converts atmospheric pressure into a voltage signal that modifies the basic duration of the fuel injection discharge.
Brake Pedal Position Switch
The brake pedal position switch signals the ECM when the brake pedal is pressed.
Camshaft Position (CMP) Sensor
The CMP sensor detects the angle of camshaft as a reference for sequential fuel injection to each cylinder.
Clutch Pedal Position Switch A
The clutch pedal position switch A signals the ECM when the clutch switch pedal is pressed. When the clutch pedal position switch A is ON, the ECM turned on the shift indicator lamp (SIL) via the F-CAN.
Crankshaft Position (CKP) Sensor
The CKP sensor detects engine speed and determines ignition timing and timing for fuel injection of each cylinder.
Engine Coolant Temperature (ECT) Sensors 1 and 2
ECT sensors 1 and 2 are temperature dependent resistors (thermistors). The resistance decreases as the engine coolant temperature increases.
Engine Oil Level Sensor
This sensor detects engine oil level.
Manifold Absolute Pressure (MAP) Sensor/Intake Air Temperature (IAT) Sensor 2
IAT sensor 2 is a temperature dependent resistor (thermistor). The resistance of the thermistor decreases as the intake air temperature increases.
The MAP sensor converts manifold absolute pressure into electrical signals to the ECM.
Mass Air Flow (MAF) Sensor/Intake Air Temperature (IAT) Sensor 1
The MAF sensor contains hot wire and a thermistor. It is located in the intake air passage. The resistance of the hot wire and thermistor change due to intake air temperature and air flow. The control circuit in the MAF sensor controls the current to keep the hot wire at a set temperature. The current is coverted to voltage in the control circuit, then output to the ECM.
Shift Indicator Lamp (SIL)
The shift indicator lamp (SIL) (A) guides shift timing of the gear for better actual fuel consumption.
Better fuel economy will be obtained, if the gear is shifted when the SIL is on.
When the SIL comes on, the ECO indicator (B) will turn off. Shifting when prompted by the shift indicator, the ECO indicator will show the current fuel economy.
The shift down indicator prompts to shift to a lower gear according to the acceleration when the vehicle is climbing a hill or for faster accelerating on a level road.
The SIL will not prompt to downshift to 1st gear to avoid sudden engine braking.
Keep engine speed low to improve fuel economy
More acceleration, SIL prompt to shift down to prevent excessive looking on acceleration pedal
Hill climbing, pulling or accelerating, SIL delays shift up prompt to prevent excessive footing on acceleration pedal
Output Shaft (Countershaft) Speed Sensor
This sensor detects countershaft speed.
Vacuum Pump
Because the vacuum is not produced on the diesel engine, the vacuum pump is driven by the cam chain to produce the vacuum.