All Possible Stuff Flashcards
The process of converting an analog signal to a digital signal is referred to as what
Encoding
A protocol is a common language for data communication between control modules. What are common protocols used in heavy duty vehicles
SAE J1587, J1708 and J1939
A linear type databus may have a resistor on either end. How many ohms would that resistor be.
120 0HMS
A throttle position sensor is also called TPS. A TPS is also a …..
Potentiometer
It has three wires. Reference voltage signal and ground. The higher the voltage the faster you go
If an ECM notices a signal voltage drop of 5 V DC in a temperature sensor circuit, What will the ECM do
The ECM will make the decision that an electrical open has occurred in the sensor circuit and create an active code indicating the sensor circuit voltage is high. It should be reading less than 5 V returning to ECM after it goes through the sensor
What type of connector would allow you to communicate with the ECM on highway and off road equipment
A DDL. Diagnostic data link
In an EUI pre-injection, the fuel injector Cam lobes starts to force the fuel injector plunger down and what three things are happening
The solenoid is de-energized, the poppet valve is open and fuel is forced out of the injector by the plunger into the fuel supply passage, not the nozzle tip
During EUI Injection The cam lobe continues to force the injector plunger downward and injection can begin at any time. During injection what four things are happening
The solenoid is energized, the poppet valve is closed, injection nozzle is open and fuel is injected into the cylinder
The open end of a wrist pin snap ring should point to the _____ of the piston.
Bottom
What are the common piston oversizes?
Imperial: .010 .020 .030
Metric: 0.25, 0.50, 0.75 mm
Diesel fuel is a hydrocarbon composed of 85% ____ and 15% ____.
85% carbon and 15% hydrogen
What does a diesel engine require for complete combustion?
Sufficient air, correct amount of fuel and sufficient heat for ignition.
Injector lines are made of what?
Heavy wall seamless steel tubing
On an inline injection pump, what are the injectors required to do?
Atomize and distribute the fuel in the cylinder
What is RAM?
Random Access Memory
What is EEPROM?
Electronically Erasable Programmable Read Only Memory
On a temperature sensor, an open causes a ____ voltage code and a short causes a ____ voltage code.
Open causes a high voltage code
Short causes a low voltage code
Why should you not touch an electric injector harness or connections with the engine running?
There is high voltage present which can cause a serious shock and personal injury
Active regens require what to be injected into the exhaust stream?
Hydrocarbons
An active regen can be initiated by:
- The ECM during a driving cycle
- a DPF dash switch
- Diagnostic program
What happens when DPF soot loading reaches 80%?
- DPF light continues to flash
- Check engine light comes on
- Engine begins to de-rate
The HEST light illuminates when exhaust temps reach _____ and vehicle speed is less than ____.
450C or 842F
8 km/h or 5 mph
The DEF level reaches 0%, the stop engine lamp illuminates, engine is further de-rated and max vehicle speed is limited to ____.
8 km/h or 5 mph
The EGR reduces what emissions?
NOx
Define as the resistance of fluid to flow is?
viscosity
Two types of head gaskets are:
steel
composition
Two common valve face angles are:
30 and 45 degree
Identify the 2 types of exhaust brakes.
sliding vane type
butterfly type
RAM random access memory is a notepad. Describe it
Information or values from input sensors can be retrieved from and entered into ram. CPU uses ram when performing calculations. Ram is volatile. Whenever power is lost or disconnected the information in ram is lost
What is the percentage number of Solid Steam Valve Heat Transfer
75% of the cooling of a solid stem valve occurs between the VALVE FACE and the VALVE SEAT and 25% is transfer from the VALVE STEM to the VALVE GUIDE.
What is the percentage number of SODIUM-COOLED Steam Valve Heat Transfer
50% of the heat is from valve stem to the valve guide and this results in additional cooling
