Deck 13: Instrumentation and Warning Lamps and Warning Lamp System Diagnosis and Repair

Question 1

Federal and state laws prohibit changing the correct mileage on the odometer.

Answer 1

True

Question 2

The tachometer receives its signal from the positive side of the ignition coil.

Answer 2

False

Question 3

If equal voltage is applied to both sides of a lamp, the lamp remains off because current cannot flow.

Answer 3

True

Question 4

Before removing the instrument panel, always disconnect the battery negative cable.

Question 5

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

A) A bucking coil .
B) A low-reading coil .
C) A high-reading coil .
D) A non-reading coil .

Question 6

The speedometer displays a speed based on an electrical signal from an output shaft speed sensor.

Question 7

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) Excessive resistance in the cluster power supply circuit .
B) Faulty cluster ground circuit .
C) Shorted fuel gauge sender unit .
D) High resistance in the fuel gauge sender circuit .

Question 8

Equal pressure in both sides of a split brake hydraulic system will cause the brake warning light to come on.

Question 9

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

A) The signal from the PM generator is a DC frequency.
B) The signal from the vehicle speed sensor is modified by the VSS buffer.
C) This system uses an A/D converter.
D) The signal from the vehicle speed sensor is an AC voltage.

Question 10

In a conventional instrument cluster, all of the gauges are inoperable. What is the LEAST likely cause of this?

A) Faulty IVR.
B)Blown fuse.
C)Shorted sending unit.
D)Faulty printed circuit.

Question 11

On most vehicles, oil pressure changes are monitored by a piezoresistive sensor.

Question 12

Electromagnetic gauges use heat to produce needle movement.

Question 13

All of the following statements concerning gauge sending units are true EXECPT:

A) A gauge can use a switch as a sensor.
B)A gauge can use a thermistor as a sensor.
C)A gauge can use a piezoresistive sensor.
D)A gauge can use a variable resistor as a sensor.

Question 14

It is normal for some electromagnetic gauges to remain at their last position when the ignition is turned off.

Question 15

The oil pressure warning light will not turn off with the engine running. A shop gauge confirms good oil pressure. What is the most likely cause?

A) Faulty IVR.
B)Damaged printed circuit board.
C)Open in the wire to the oil pressure switch.
D) Short to ground in the wire to the oil pressure switch.

Question 16

What usually controls an oil pressure warning lamp?

A) Voltage drop .
B) A grounding switch .
C) A grounding sensor .
D) Any of these choices .

Question 17

Before replacing the fuel gauge sender unit, clean the ground connections and test for proper operation.

Question 18

An electronically controlled instrument cluster is being diagnosed for no speedometer operation. Which of the following statements is most correct?

A) If the BCM and/or cluster module passes it's self-test, the fault is probably in the vehicle speed sensor circuit.
B)If the speedometer does not work but the odometer does, then the problem is probably in the vehicle speed sensor circuit.
C)If the speedometer fails to move during the self-test, the problem is probably in the vehicle speed sensor circuit.
D) All of these choices.