The ECU/ECM monitors fuel pressure to control the amount and timing of fuel being transferred from high-pressure fuel pump to the common rail. The ECU uses the pressure signal to determine if fuel rail pressure is adequate for the current operating condition. The ECU will command more or less fuel from the high-pressure fuel pump by altering the signal to the fuel metering unit and pressure regulating valve (PRV).
The fuel is determined by the fuel level in fuel tank with a float sensor which provides a change in resistance as a result of the fuel level. Together with the electric fuel pumpand the fuel filter, it is part of the in-tankunit. These are installed in the fuel tank(gasoline or diesel fuel) and provide for anefficient supply of clean fuel to the engine.
The potentiometer’s wiper spring is fixed tothe float lever by a pin. Special wipers (contact rivets) provide the contact between thewiper spring and the potentiometer resistance tracks, and when the fuel level changesthe wipers move along these tracks and generate a voltage ratio which is proportional tothe float’s angle of rotation. End stops limitthe rotation range of 100° for maximum andminimum levels as well as preventing noise. The Operating voltage varies from 5-13 V.
The fuel sender unit transmits the current fuel level from the fuel tank, providing a signal for the vehicle's dashboard or instrument cluster. It also triggers a low fuel warning when the level is low.Due to this feature, we will avoid the vehicle stoppage in some conditions.
The fuel flow sensor is to monitor the flow rate of the fuel in the fuel system. It’senable precise calculation of engine fuel consumption rate by measuring the differential fuel flow across the fuel injectors with supply and return values.
On electronically controlled fuel-injectionsystems, the fuel quantity is metered to theengine precisely either intermittently or continuously. The required fuel quantity is injected precisely thanks to the evaluation ofsuch variable/adjustable parameters as injection duration, setting of the metering unit,injection pressure, fuel temperature etc.
The difference betweenthe fuel delivered from the tank and theamount of fuel which flowed back to itwas applied as the basis for calculating theamount of fuel that had actually been used.
The purpose of this sensor is to measure the exhaust gases temperature which flows through the catalyst.
This catalyst temperature data is closely monitored by the ECU (electronic control unit) / ECM (electronic control module) to ensure the engine optimal temperature, after treatment components life such as exhaust throttle, exhaust recirculation systems, diesel particulate filter, diesel oxidation catalyst, and engine pollutants control.
This sensor always monitors the temperature and pressure of catalytic converter. If the temperature increases, the ECU will calculate the other after treatment components electronic signal data and derates the engine performance.
The purpose of this sensor is to measure the urea solution pressure which injected into the selective catalytic reduction catalyst. The main purpose of this dosing is to reduce the nitrous oxide reduction. This method is also called as external engine emission control method.
This system equipped with dedicated urea dosing pump which pumps the pressurized urea into the catalytic converter. This pump operated by the dosing system, If the pressure is not maintained upto the desire value, the ECU will trigger the DTC to correct the fault and meanwhile the fuel flow rate will be controlled until this DTC gets corrected.
A Hall position fuel float uses a Hall Effect sensor to determine the float position in the fuel tank, and convert the signal into an electrical signal to indicate the fuel level in vehicle's dashboard or instrument cluster.
The above highlighted component is a “Engine Oil Pump”. Please move it to its respective section. This is not a common rail valve.
This fuel flow sensor is to monitor
This reed switch type fuel level sensor equipped with a float containing a magnet. As the fuel level changes, the float interchanges causing the magnet to activate the reed switch. This reed switch consists of two ferromagnetic blades that close when a magnetic field is applied to complete an electrical circuit indicating the fuel level.