Electronic Diesel Injection Systems Quiz

Mack calls their electronic engine control system:

DDEC

CELECT

PEEC

V-MACK

Correct! Wrong!

Cummins calls their electronic engine control system:

DDEC

CELECT

PEEC

V-MACK

Correct! Wrong!

Detroit Diesel calls their electronic engine controls:

DDEC

CELECT

PEEC

V-MACK

Correct! Wrong!

The early Caterpillar electronic engine control system was called:

DDEC

CELECT

PEEC

V-MACK

Correct! Wrong!

Technician A says that a HEUI (hydraulic electronic unit injector) does not require adjustment. Technician B says that an EUI (electronic unit injector) does not require adjustment. Who is correct?

technician A

technician B

both technician A and B.

neither A or B

Correct! Wrong!

With electronically controlled engines it is possible to program _____________.

horsepower.

governor type.

max road speed.

all of the above.

Correct! Wrong!

The throttle position sensor assembly on most electronically controlled engines contains:

potentiometer.

cruise control controller switch.

accellerometer.

vehicle speed limiting.

Correct! Wrong!

Electronic diesel engines are all programmed to shut down immediately in the event of low oil pressure or high coolant temperature levels.

True

False

Correct! Wrong!

Modern ECM''s electronic circultry tend to operate at temperatures that would cause them to over-heat if not adequately maintained at a safe temperature. Manufacturers use _________________ to help cool them.

fuel flowing through a cooling plate mounted to the ECM.

cooling fins and high air flow.

are adapted to the air conditioning system, and uses

both A and B.

Correct! Wrong!

Electronic controlled diesel engine ECM operates on a reference voltage of 12 volts, plus or minus 5 volts.

True.

False.

Correct! Wrong!

Active faults, refer to faults or conditions that have previously happened.

True.

False.

Correct! Wrong!

Technician A says that the ECM is designed and programmed to record and retain certain codes and engine history, but all records are erasable by the customer. Technician B says that if you disconnect the power from the ECM, the PROM will have to be reprogrammed. Who is correct?

technician A

technician B

neither A nor B

both A and B

Correct! Wrong!

Inactive fault codes are faults stored in memory but are not currently happening.

True.

False.

Correct! Wrong!

Technician A says that the ECM uses feedback from some engine actuators to control the engine operation. Technician B says that the actuators are controlled by the ECM. Who is correct?

Technician A.

Technician B.

both Technician A and B.

neither A nor B.

Correct! Wrong!

Technician A says that some engines require two individual sensors to indicate engine speed and position. Technician B says that some engines use one sensor to indicate engine speed and position. Who is right?

Technician A.

Technician B.

both A and B.

neither A nor B.

Correct! Wrong!

SAE (society of automotive engineers) mandates that all diesel engines shall use electronic controlled diesel fuel injection system.

true

false

Correct! Wrong!

How do you the electronic unit injector (EUI) control fuel timing.

by varying plunger stroke.

by controlling the EUI solenoid.

by altering the fuel rail pressure.

by opening the throttle shaft.

Correct! Wrong!

What is the primary objective when the progressive shift option is enabled for heavy trucks?

longer transmission life.

improved fuel economy.

frustrate the driver.

stabilize engine oil temperature.

Correct! Wrong!

Electronic diesel engine fault codes may indicate:'

engine overheat.

low differential oil.

turbo speed.

all of the above.

Correct! Wrong!

Technician A says that in some systems, the ECM may also engage the air conditioning compressor to increase the retarding effort when the engine brake is used. Technician B says that in some systems, the ECM may also engage the fan to increase the retarding effort when the engine brake is used. Who is right?

Technician A.

Technician B.

neither A nor B.

both A and B.

Correct! Wrong!

Technician A says that to check some injection systems, you can hold down each injector plunger to find the miss or weak firing injector. Technician B says to isolate a faulty electronic unit injector, perform a cylinder balance test, then switch injector positions and retest, to confirm a faulty injector. Who is correct?

Technician A.

Technician B.

both A and B.

neither A nor B.

Correct! Wrong!

In order to read or calibrate an electronic diesel engine using a laptop computer, requires the use of a specific engine adapter or translator and a version of the engine manufacturers software.

True.

False.

Correct! Wrong!

Technician A says that to effectively and safely find electronic engine problems, you should use a high resistance digital multimeter. Technician B says to be able to diagnose electronic engine faults you must have a good understanding of high pressure hydraulic injection systems. Who is right?

Technician A.

Technician B.

neither A nor B.

both A and B.

Correct! Wrong!

Technician A says that on the Cummins N14 the injectors are mechanically actuated and have individual solenoids to control fuel metering and timing.

Technician A.

Technician B.

neither A nor B.

both A and B.

Correct! Wrong!

Technician A says that it is sometimes acceptable to repair electronic engine wiring with solder and shrink tube connections. Technician B says that using a digital volt meter will cause damage to the ECM. Who is correct?

Technician A.

Technician B.

neither A nor B.

both A and B.

Correct! Wrong!

When voltage tests are made on electronic circuit components, the circuit should be:

open.

shorted.

energized.

grounded.

Correct! Wrong!

At any one particular speed, the output signal of a Hall Effect sensor that would be received by an ECM would be read as a _________________ signal.

AC voltage

DC voltage

digital on-off

analog variable

Correct! Wrong!

Which of the following are inserted into ECM and the wiring terminal sockets to enable testing by digital multimeter probes and minimize potential damage?

cycling breakers

noncycling breakers

dummy terminals

diagnostic forks

Correct! Wrong!

Which of the following statements is the most correct?

It is safe to disconnect individual sensors one at a time while the engine is running.

A powered test light is an important tool for diagnostic procedures.

Correct! Wrong!

Which of the following aconyms does not relate to computers and not belong in this list?

ECM

BLT

ECU

PCM

Correct! Wrong!

Computer memory is considered to be volatile or non-volatile memory. Which of the following would be considered volatile?

EEPROM

RAM

ROM

FEPROM

Correct! Wrong!

A computer system monitor battery charge voltages at all times to ensure:

that the alternator develops the correct output.

the sensors are operating and sending signals with a known voltage input.

to enable the check engine light if a fault is found.

that voltages do not spike and harm light circuits.

Correct! Wrong!

Input sensors generally monitor engine systems for correct operation. Which is not?

rate of injection.

manifold temperatures.

air box or plenum pressures.

crankshaft speeds.

Correct! Wrong!

Thermistors, pulse generators and potentiometers are all different types of:

actuators.

analog to digital convertors.

input sensors.

output devices.

Correct! Wrong!

A HEUI fuel injection system involves an engine oil hydraulic system and a diesel fuel hydraulic system.

True.

False.

Correct! Wrong!

Mechanically actuated injections systems cannot be controlled electronically.

True.

False.

Correct! Wrong!

An HEUI fuel injection system uses multiple hydraulic actuation pressures within its system.

True.

False.

Correct! Wrong!

The injection actuation pressure control valve, also called the rail pressure control valve, alters the hydraulic pressure in a HEUI system by varying the opening of a drain port.

True.

False.

Correct! Wrong!

Certain instructions programmed into a PROM, establishing certain minimum and maximum parameters of a fuel injection system, cannot be changed beyond design parameters or possible engine damage and warranty disqualification will result.

True.

False.

Correct! Wrong!

If engine idle speed is changed on the parameters of an EPROM memory chip, the ECM will automatically recognize the new settings.

True.

False.

Correct! Wrong!

The modern ECM and its memory systems can store all kinds of information, except:

total engine hours.

total oil consumption.

total idle time.

total of starts.

Correct! Wrong!

The HUEI fuel injector is refilled with diesel fuel during the end of injection stage.

True.

False.

Correct! Wrong!

On an electronic engine, which sensor notifies the ECM when a cylinder is in the firing location?

throttle position sensor.

throttle validation switch.

timing reference sensor.

electronic distribution unit.

Correct! Wrong!

When trouble shooting new electronic systems with their individual diagnostic trouble codes and related information with your scanner or laptop, changes to settings cannot be performed without the:

fault codes numbers.

access codes.

flash codes.

sequence of flashing lights.

Correct! Wrong!

An engine problem that is slightly outside the parameters of the ECM will energize the stop engine light.

True.

False.

Correct! Wrong!

Engine computer systems will monitor sensor inputs for pressures, temperatures and levels because these could result in a catastrophic engine failure.

True.

False.

Correct! Wrong!

Wiring harness and connectors are often the cause of system failures and trouble codes.

True.

False.

Correct! Wrong!

When accessing information and reading fault codes from an ECM, you must have the engine running and up to normal operating temperature.

True.

False.

Correct! Wrong!

Customer programmable parameters are those that can be changed at a dealership in order to customize features the ECM can control, as a convenience for the customer.

True.

False.

Correct! Wrong!

In some cases, customer programmable features (PROM) can exceed the parameters established by the engine manufacturer.

True.

False.

Correct! Wrong!

In most computerized fuel systems, what is the voltage in the sensing circuits?

2 volts.

5 volts.

12 volts.

24 volts.

Correct! Wrong!

Once a fault code has been retrieved from the ECM , the component identified should be exchanged for a new one.

True.

False.

Correct! Wrong!

HEUI fuel injector operation involves distinct injection stages. They are:

pre-injection stage.

injection stage, which includes pilot, delay and main fuel injection.

end of injection stage.

all of the above.

Correct! Wrong!

If 1000 lbs. of actuation oil pressure was applied to a HEUI injector, what would be the potential injection pressure?

2000 lbs.

3000 lbs.

6000 lbs.

8000 lbs.

Correct! Wrong!

In HPCR fuel system, fuel delivery pressure to the injectors is controlled by:

pump speed and flow.

the rail pressure control valve.

Correct! Wrong!

In HPCR fuel injection system, the injector needle valve is opened when

the solenoid is energized, which increases pressure on the needle valve.

the solenoid is de-energized, which increases pressure on the needle valve.

the solenoid valve is energized, which decreases pressure on the intermediate valve.

the solenoid is de-energized which increases pressure on the intermediate valve.

Correct! Wrong!

If the wire attached to the engine crank or cam position sensor or sensors were to come off, the engine would:

set a ode, light SEL, de-rate to a lesser horsepower.

set a code, light SEL, continue to operate.

would die, or fail to restart after shutdown.

depending on the system, all of the above.

Correct! Wrong!

Transient voltages, which may affect engine RPM at idle, can be overruled by the use of a:

engine position sensor.

potentiometer.

idle validation switch.

all of the above.

Correct! Wrong!

Which type of sensor would be potentiometer?

throttle position sensor.

oil temperature sensor.

speed sensor.

O2 sensor.

Correct! Wrong!

Which sensor reduces the chance of turbo damage due to overspeeding at high altitudes?

manifold air pressure sensor.

ambient air pressure sensor.

turbo boost sensor.

manifold air temperature sensor.

Correct! Wrong!

An inactive fault code will still flash out a code on the check engine light and the stop engine light.

true.

false.

Correct! Wrong!

Technician A says that the PCM and the electronic unit injector controls the metering of fuel into the cylinder. Technician B says that the PCM and the electronics unit injector controls the timing of the fuel injected into the cylinder. Who is correct?

Technician A.

Technician B.

Both A and B.

neither A nor B.

Correct! Wrong!

With an electronically controlled engine there are usually three wiring harnesses connected to the ECM. These harnesses are 1/ the OEM (original equipment manufacturer), 2/ the actuator harness, and 3/ the:

throttle position sensor harness.

engine fan control harness.

input sensor harness.

data link harness.

Correct! Wrong!

Fault codes can be retrieved by the use of a diagnostic data reader.

True.

False.

Correct! Wrong!

An engine temperature thermistor sensor is checked using:

a voltmeter between the terminals while the thermistor is hot.

an ohmmeter between the terminals while the thermistor is cold or hot.

a digital multimeter on the voltage setting between the terminals while the thermistor is cold.

none of the above.

Correct! Wrong!

A thermistor is tested by measuring:

low temperature against high resistance.

resistance according to changes in diaphragm pressure.

output voltage according to resistance value changes made by the ECU.

resistance which varies according to its temperature.

Correct! Wrong!

The prime responsibility of an electronic control module is to:

monitor and control engine performance

send and receive either analog or digital signals as required.

store information for referance parameters, past performance and fault identification

all of the above

Correct! Wrong!

Engine protection is incorporated into the computerized systems because it can sense.

normal operating speeds.

crankshaft or camshaft motion.

operator demands.

coolant temperature and oil pressure.

Correct! Wrong!

An important consideration when working around computerized systems is to:

always disconnect the batteries as soon as the machine is stopped.

never touch any wiring.

do not use any test instruments or procedures not recommended in the service manuals.

attache chargers to the batteries one at a time.

Correct! Wrong!

The computer controls the fuel injection process by gathering information from the sensors.

True.

False.

Correct! Wrong!

The random access memory is used for:

permanent storage of information.

temporary storage of information.

operation of sensors.

turning on the warning lights.

Correct! Wrong!

The memory that cannot be changed or written to is the:

PROM

RAM

ROM

EPROM

Correct! Wrong!

Computer controlled injection system are more accurate than mechanically, hydraulically or pneumatically controlled systems.

True.

False.

Correct! Wrong!

The hydraulic actuation oil pressure in the HEUI system is controlled by the ECM and the:

fuel pressure sensor.

IAP control valve.

rail pressure sensor.

combination (pairing) of rail and fuel pressure.

Correct! Wrong!

The amount of fuel injected by an electronic unit injector is typically controlled by pulse width modulation. Pulse width can be identified with:

degrees of crankshaft rotation.

pressure of fuel injected.

time the injector solenoid is de-energized or energized.

all of the above.

Correct! Wrong!

Electronic unit injectors are actuated by:

a high pressure fuel pump.

a high pressure oil pump.

a mechanical injector drive mechanism.

an electronic drive mechanism.

Correct! Wrong!

An ECM cooling plate is used to:

cool the incoming air for better performance, more dense air.

cool the incoming fuel for better performance, less then 150 degrees F.

compensate fuelling to the engine relative to the fuel density.

protect electronic units from heat.

Correct! Wrong!

In the EUI system, the ECM ___________ to initiate the injection process.

de-energizes the injector solenoid

opens the poppet valve

increases the fuel transfer pressure

energizes the injector solenoid

Correct! Wrong!

Technician A says the powertrain control module (PCM) contains emission-related information codes. Technician B says you must have a scan tool and software to clear any emission codes. Who is right?

A only.

B only.

both A and B.

neither A nor B.

Correct! Wrong!

What is the meaning of the abbreviation "DTC" as it pertains to the error codes on the modern diesel engine?

Please select 2 correct answers

Drive Train Codes.

Diagnostic Trouble Codes.

Direct Trouble Codes.

Direct Transmission Codes

Correct! Wrong!

Which is most likely to cause damage or failure when used to check connections on the electronic modules?

digital ohmmeter.

digital multimeter.

LED test light.

test light.

Correct! Wrong!

Technician A says that the customer option codes can be changed in the electronic systems with a generic scan tool. Technician says in some cases, changing the fuel settings with a generic scan tool could result in poor engine performance. Who is right?

A only.

B only.

both A and B.

neither A nor B.

Correct! Wrong!

Technician A says that the throttle position sensor is interfaced to a 5-Volt reference. Technician B says when the throttle is manually opened, the scan tool should read a low voltage. Who is right?

A only.

B only.

both A and B.

neither A nor B.

Correct! Wrong!

Technician A says the EMC connectors should never be probed through the weather pack seals. Technician B says a test kit should be used to test connectors. Who is right?

A only.

B only.

both A and B.

neither A nor B.

Correct! Wrong!

Sometimes, two or more sensors are used to monitor actions in the computerized systems to verify relationship signals. Which of the sensors below would present a pairing for a systems relational signal? (please answer all that are correct)

throttle position sensor and vehicle speed sensor.

cam sensor and crank sensor.

fuel pressure sensor and fuel temperature sensor.

ambient air pressure sensor and boost pressure sensor.

Correct! Wrong!

Excessive heat can destroy solid state devices on trucks and equipment, like ECM''s. Technition A says that many ECM''s are air cooled with large fins. Technition B says that many ECM''s are cooled by cold plates with fuel circulation. Technition C says that some ECM''s are cooled by installing them on air ducts. Technition D says that some ECM''s are cooled by circulation of refrigerant from the A.C. Who is right?

Technician A

Technician B

Technician C

Technician D

Correct! Wrong!