Test Bank For Computerized Engine Controls 10th Edition by Steve V. Hatch

Name Clas Dat : s: e: Chapter 3 Common Components for Computerized Engine Control Systems 1. What type of sensor is a throttle position sensor? a. c. ANSWER: POINTS: Potentiometer Piezoelectric diaphragm b. NTC thermistor d. Piezoresistive diaphragm 2. What voltage will be produced by a zirconium dioxide O2 sensor when the air-fuel ratio is on the rich side of stoichiometric? ANSWER: POINTS: d 1 b 1 c 1 a. 0 mV c. 450 mV b. 100 mV to 450 mV d. 450 mV to 900 mV 3. What scale on a DVOM should be used to test a zirconium dioxide O2 sensor’s signal? a. An AC voltage scale c. A resistance scale ANSWER: POINTS: b. A DC voltage scale d. A diode test scale 4. All of the following sensors vary resistance so as to modify a voltage signal EXCEPT: a. Potentiometer c. Zirconium dioxide oxygen sensor ANSWER: POINTS: b. NTC Thermistor d. Piezoresistive diaphragm 5. On a fuel injected engine, what is the most probable result of a faulty (worn) TPS that results in a voltage drop-out as the throttle is opened? a. c. ANSWER: POINTS: Cranks but won’t start Starter cranks slow b. Hesitates on acceleration d. Engine diesels on shutdown 6. How will an increase in temperature from 50oF to 220 oF affect the resistance of an NTC thermistor? a. The resistance decreases c. The resistance will be unaffected ANSWER: POINTS: b. The resistance increases d. The resistance should go to “infinity” a 1 Copyright Cengage Learning. Powered by Cognero. Page 1 a 1 b 1 Name Clas Dat : s: e: Chapter 3 Common Components for Computerized Engine Control Systems 7. In the figure above, if there was an open at terminal “C”, what would the voltage signal to the PCM be? ANSWER: POINTS: d 1 a. c. 0 volts About 31⁄2 volts b. About 11⁄2 volts d. 5 volts 8. In the figure above, as the engine coolant temperature sensor’s resistance decreases, how will the voltage signal to the computer change? a. The voltage signal decreases c. The voltage signal is unaffected ANSWER: POINTS: 9. If the vacuum hose to a MAP sensor were to rupture, what would the likely result be? a. The engine would continue to run well because the O2 sensor is the primary sensor c. The PCM would go into open loop and run the engine excessively rich ANSWER: POINTS: 10. What is the “speed density formula” used to determine? a. How much air is entering the engine b. How much fuel is entering the engine Copyright Cengage Learning. Powered by Cognero. Page 2 b. The voltage signal increases d. The sensor begins producing a digital frequency b. The PCM would go into open loop and run the engine excessively lean d. The PCM would see this sensor as being out of normal operating limits a 1 c 1 Name Clas Dat : s: e: Chapter 3 Common Components for Computerized Engine Control Systems c. How much exhaust back pressure is present ANSWER: POINTS: 11. Which of the following sensors may be used in place of the “speed density formula”? ANSWER: POINTS: a. MAP sensor c. MAF sensor b. VAF meter d. DPFE sensor a 1 c 1 d 1 12. Which of the following best describes how a permanent magnet sensor operates? a. It modifies a reference voltage signal c. It generates a DC digital voltage signal ANSWER: POINTS: b. It generates a DC analog voltage signal d. It generates an AC voltage signal d. How much CO and HC is being produced during combustion 13. Two technicians are discussing how to test a permanent magnet vehicle speed sensor. Technician A says that you should test the coil’s resistance and compare it to specification. Technician B says that you should set your DVOM to the “DC volts” scale to test the sensor’s ability to produce voltage. Who is correct? a. Technician A only c. Both technicians ANSWER: POINTS: b. Technician B only d. Neither technician 14. A digital Hall effect sensor consists of all of the following EXCEPT: a 1 d 1 a 1 a. a shutter wheel with vanes and windows c. a Hall effect crystal ANSWER: POINTS: 15. What type of signal does a Hall effect switch send to the PCM? b. a permanent magnet d. a light emitting diode a. A digital DC voltage c. An analog DC voltage ANSWER: POINTS: b. A digital AC voltage d. An analog AC voltage 16. Which of the following types of sensors cannot be used as a RPM reference sensor? a. Potentiometer c. Optical b. Permanent magnet d. Hall Effect Copyright Cengage Learning. Powered by Cognero. Page 3 Name Clas Dat : s: e: Chapter 3 Common Components for Computerized Engine Control Systems ANSWER: a POINTS: 1 17. Which of the following sensors cannot produce or generate a voltage signal? a. Zirconium dioxide oxygen sensor c. Piezoelectric sensor ANSWER: POINTS: b. Permanent magnet sensor d. Potentiometer 18. Technician A says that a switch in a “pull-up circuit” provides voltage to the computer when it is closed. Technician B says that a switch in a “pull-down circuit” provides a ground to the computer when it is closed. Who is correct? a. c. ANSWER: POINTS: Technician A only Both technicians b. Technician B only d. Neither technician 19. Most often, how does the PCM energize an output actuator? a. It supplies 5 volts to the actuator c. It supplies secondary ignition voltage to the actuator ANSWER: POINTS: c 1 b. It supplies battery voltage to the actuator d. It completes the actuator’s ground path d 1 20. Technician A says that if a relay is normally open, it must be energized in order to complete the controlled circuit. Technician B says that if a solenoid-operated valve is normally closed, it must be energized in order to allow flow through it.Who is correct? a. c. ANSWER: POINTS: Technician A only Both technicians b. Technician B only d. Neither technician Page 4 d 1 c 1