Question 1

A vehicle's electronic digital fuel gauge is always indicating a full tank. All of the other instrument gauges are operating correctly. Which of the following is the most likely cause of this problem?

Accepted Answer

The answer of A vehicle's electronic digital fuel gauge is...

Question 2

There are three types of sending units associated with electromechanical gauges: a thermistor, a piezoresistive sensor, and a mechanical ____ resistor.

Accepted Answer

The two types of sending units mentioned before (thermistor and piezoresistive sensor) are both variable resistors, meaning their resistance changes based on the temperature or pressure they are measuring. Therefore, it follows that the third type of sending unit would also be a variable resistor, making B the best choice.

Question 3

Unlike gauge sending units, the sending units for a warning light are nothing more than simple ____.

Accepted Answer

Sending units for warning lights are essentially on/off switches that trigger the light to come on when a certain condition is met (e.g. low oil pressure). They do not measure or provide any data or resistance values like thermistors or resistors, nor do they emit light themselves like lamps.

Question 4

Technician A says when testing a system using an IVR, use a voltmeter to test for regulated voltage at a common point. Technician B says if regulated voltage is within specifications, you must replace the printed circuit board. Who is correct?

Accepted Answer

Technician A is correct. When testing a system using an IVR, it is important to use a voltmeter to test for regulated voltage at a common point. Technician B is incorrect. If regulated voltage is within specifications, it does not necessarily mean that the printed circuit board needs to be replaced.

Question 5

Technician A says a normally open switch is used in most coolant temperature warning light circuits. Technician B says most oil pressure warning circuits use a normally closed switch. Who is correct?

Accepted Answer

Both statements are correct. A normally open switch is used in most coolant temperature warning light circuits, which closes to complete the circuit when the coolant temperature exceeds a certain threshold, activating the warning light. Most oil pressure warning circuits use a normally closed switch that opens when sufficient oil pressure is present, turning off the warning light.

Question 6

The electromechanical gauge acts as a(n) ____since the gauge reading changes with variations in resistance.

Accepted Answer

The answer of The electromechanical gauge acts as a(n) ____since...

Question 7

Electromagnetic gauges produce needle movement by magnetic forces instead of ____.

Accepted Answer

The answer of Electromagnetic gauges produce needle movement by magnetic...

Question 8

On most systems, the odometer and speedometer receive their input from the vehicle ____ sensor.

Accepted Answer

The speedometer and odometer in most vehicles receive their input from the vehicle speed sensor, which measures the rotation speed of the transmission or wheels to calculate speed and distance traveled.

Question 9

Which of the following is NOT true about a quartz analog speedometer system?

Accepted Answer

The signal from the PM (Permanent Magnet) generator in a quartz analog speedometer system is an AC frequency, not a DC frequency. This is because the output of a PM generator varies with the speed of the vehicle, producing an alternating current (AC) signal that reflects the vehicle's speed.

Question 10

Technician A says the thermistor sensor measures pressure. Technician B says a voltmeter is used to test a thermistor sensor unit. Who is correct?

Accepted Answer

Technician B is correct because a voltmeter can be used to test a thermistor sensor unit by measuring its resistance, which changes with temperature. A thermistor does not measure pressure; it measures temperature.

Question 11

Which of the following is NOT contained in a three-coil gauge?

Accepted Answer

A three-coil gauge contains a bucking coil, a low-reading coil, and a high-reading coil. It does not contain a non-reading coil.

Question 12

What usually controls an oil pressure warning lamp?

Accepted Answer

A ground switch is the most common method of controlling an oil pressure warning lamp. When the oil pressure in the engine falls below a certain level, the switch closes the ground circuit for the lamp, causing it to illuminate on the dashboard. This alerts the driver to the potentially serious problem of low oil pressure. While voltage drop and ground sensors can also be used to control warning lamps, they are less common in oil pressure systems.

Question 13

Which of the following is NOT true about a quartz analog speedometer system?

Accepted Answer

The signal from the PM (Permanent Magnet) generator in a quartz analog speedometer system is an AC frequency, not a DC frequency. This is because the output of a PM generator varies with the speed of the vehicle, producing an alternating current (AC) signal that reflects the vehicle's speed.

Question 14

Computer-driven quartz swing needle displays are similar in design to the ____ electromagnetic gauges used in conventional analog instrument panels.

Accepted Answer

Computer-driven quartz swing needle displays are similar in design to the d'Arsonval electromagnetic gauges used in conventional analog instrument panels.

Question 15

Most electronic instrument clusters (EICs) have a(n) ____ display each time the ignition switch is turned on.

Accepted Answer

Most EICs have a "prove-out" display each time the ignition switch is turned on, which means that all the warning indicators and gauges will light up briefly to confirm that they are functioning properly. This helps the driver to identify any issues with the instrument cluster before starting to drive.

Question 16

A(n) ____ is a device that displays the measurement of a monitored system by the use of a needle or pointer that moves along a calibrated scale.

Accepted Answer

A gauge is specifically designed to display measurements of a system through a needle or pointer on a calibrated scale. Actuators, switches, and sensors all serve different functions in a system and are not necessarily designed to display measurements in this way.

Question 17

The sending unit is the ____ for the gauge.

Accepted Answer

The sending unit is the sensor for the gauge.

Question 18

A vehicle's electronic digital fuel gauge is always indicating a full tank. All of the other instrument gauges are operating correctly. Which of the following is the most likely cause of this problem?

Accepted Answer

A shorted fuel gauge sender unit will cause the fuel gauge to always indicate a full tank because it is constantly sending a signal that the tank is full. Excessive resistance, a faulty ground circuit, or high resistance in the fuel gauge sender circuit would all cause inaccurate readings, but not a consistently full reading.

Question 19

A gauge that constantly reads low when the ignition switch is in the RUN position indicates an open in the ____.

Accepted Answer

The answer of A gauge that constantly reads low when...

Question 20

The computer-driven instrument cluster uses a microprocessor to process information from various sensors and to control the ____.

Accepted Answer

The microprocessor in the computer-driven instrument cluster processes information from various sensors in order to control the gauge display.

Quiz 12: Instrumentation and Warning Lampsinstrumentation and Warning Lamp System Diagnosis and Repair

A vehicle's electronic digital fuel gauge is always indicating a full tank. All of the other instrument gauges are operating correctly. Which of the following is the most likely cause of this problem?

There are three types of sending units associated with electromechanical gauges: a thermistor, a piezoresistive sensor, and a mechanical ____ resistor.

Unlike gauge sending units, the sending units for a warning light are nothing more than simple ____.

Technician A says when testing a system using an IVR, use a voltmeter to test for regulated voltage at a common point. Technician B says if regulated voltage is within specifications, you must replace the printed circuit board. Who is correct?

Technician A says a normally open switch is used in most coolant temperature warning light circuits. Technician B says most oil pressure warning circuits use a normally closed switch. Who is correct?

The electromechanical gauge acts as a(n) ____since the gauge reading changes with variations in resistance.

Electromagnetic gauges produce needle movement by magnetic forces instead of ____.

On most systems, the odometer and speedometer receive their input from the vehicle ____ sensor.

Which of the following is NOT true about a quartz analog speedometer system?

Technician A says the thermistor sensor measures pressure. Technician B says a voltmeter is used to test a thermistor sensor unit. Who is correct?

Which of the following is NOT contained in a three-coil gauge?

What usually controls an oil pressure warning lamp?

Which of the following is NOT true about a quartz analog speedometer system?

Computer-driven quartz swing needle displays are similar in design to the ____ electromagnetic gauges used in conventional analog instrument panels.

Most electronic instrument clusters (EICs) have a(n) ____ display each time the ignition switch is turned on.

A(n) ____ is a device that displays the measurement of a monitored system by the use of a needle or pointer that moves along a calibrated scale.

The sending unit is the ____ for the gauge.

A vehicle's electronic digital fuel gauge is always indicating a full tank. All of the other instrument gauges are operating correctly. Which of the following is the most likely cause of this problem?

A gauge that constantly reads low when the ignition switch is in the RUN position indicates an open in the ____.

The computer-driven instrument cluster uses a microprocessor to process information from various sensors and to control the ____.