What is the advantage of putting a relay in a headlight circuit?
Which of the following symbols indicate an item that shows a normally closed switch?
Which of the following symbols indicate an item that shows a resistor?
Which symbols below indicate the symbol for a diode?
Which of the symbols below indicate the symbol for a relay?
A short can be considered to be "copper to copper" in a circuit.
Which of the symbols below indicate the symbol for a wire splice?
Which of the symbols below indicate the symbol for a simple coil?
While testing a solenoid coil, an ohmmeter reads an infinite or O.L. reading on the auto range setting. What is likely to be the problem?
Technician A says that circuit protection devices open when the current in the circuit falls below a predetermined level. Technician B says excessive current results from a decrease in the circuit''s resistance. Who is right?
Total current in a parallel lighting circuit will divide between branches according to:
When testing a magnetic pick-up coil (opens, shorts and grounds), what should your meter be set to?
Ohmmeter readings while testing a good diode should read:
When checking the signal lights on a pick-up truck, a technician finds that the left turn signal works fine but the right side lights comes on but do not flash. A possible problem with the system might be:
To paraphase Ohm''s Law, it states that:
A technician is diagnosing a tractor trailer units lighting system. After turning on the marker light and head switches, he notices that none of the marker lights are working, only the head lights are on. The logical first place to look for the problem would be to check:
A technician needs to check for voltage in an electrical circuit. Technician A says a 12-volt test light is used by attaching one lead to a known good voltage source, then probing various points along a circuit. Technician B says one lead of the test light should be grounded, and the other used to prove various points along a circuit. Who is right?
On a vehicle with a 12-volt system, a switched circuit feeds a pair of 50-watt auxiliary lights. What size of fuse would be required to protect the circuit and provide a 15% cushion for surges?
When using a voltmeter to perform a voltage drop test in a circuit, the leads should be connected in what way?
The blower motor in a truck is running very slowly. An ammeter shows a low current flow. This could be caused by:
The taillight bulbs are inoperative and the tail light fuse burned out. A 12-volt test light is installed in place of the fuse, the test light comes on, but the taillight bulb remains out. When the connector near the bulb is disconnected, the 12-volt test light remains on. What may be the problem?
When the driver''s door of the vehicle is opened, the interior lights illuminate, but dimly. The problem is most likely to be:
When installing new bulbs into sockets, a good idea to prevent possible corrosion of the contact surfaces is by:
The Western Union splice is a proper and complete repair to a wire harness providing you:
A truck is having an intermittent fault with its high beam headlights, occasionally when the floor mounted dimmer switch is activated, the headlights go out. The least likely cause would be:
A problem is encountered with the interior cab lights of a truck. When the bulb is out of the socket and the fuse is in place, everything is fine except the light does not work. Every time that a courtesy light bulb is replaced, the 15 amp fuse protecting that circuit burns out after a few seconds. What is the likely cause?
The use of Halogen headlight bulbs requires different procedures for installation and use. Which of these do not apply?
In the figure below, if the clearance light switch has failed, what would happen in the circuit?
A single clearance light in a circuit glows dimly. A technician connects a test light to the bulb socket terminal and the test light burns at normal brightness. What is likely to be the problem?
A non-computerized vehicle''s oil pressure warning light fails to come on, even when the engine is shut down. All of the following are possible causes of the problem EXCEPT a:
Which of the following is NOT used when checking a circuit for continuity?
When using a 12-volt test lamp to test for voltage, all of the following are true EXCEPT:
Checks are being made to determine the cause of a battery going dead after a few days when the equipment is sitting. Which of these statements is most correct?
Which of these is the LEAST likely cause of a dim headlight?
In the figure shown below, the backup light circuit fuse keeps blowing. Technician A uses an ohmmeter to check the circuit across the backup light fuse contacts. Technician B uses an ammeter to check the circuit across the backup light fuse contacts. Who is right?
A backup light circuit is grounded between the switch and the bulbs. What would be the result?
All the dash lights on a dash panel do not work. The least likely problem would be:
A truck that has a fuel dash gauge does not change regardless of the level of fuel in the tank. To determine if the problem is in the dash gauge or the sender, the technician would first:
When diagnosing a problem of whether the oil pressure sender is delivering accurate readings to the oil pressure dash gauge, a technician would
Which of the following symbols indicate an item that will protect an electrical circuit?
What is the function of the pyrometer?
When checking a mechanical water temperature gauge for an erratic reading, a correct test procedure would be:
It is acceptable to use an ordinary test light on:
A customer says the electric horn on a truck will not stop blowing. What could be the cause?
The vehicle''s electric horn does not work when the horn button is depressed. To test the horn circuit, you would:
A Technician should not use a jumper wire to test:
An engine coolant warning light fails to come on whenever the vehicle''s key is turned on or when the vehicle is started. All of the following are possible causes EXCEPT:
Series circuits have _______________ path for current flow:
Current flow is _______________ parts of a series circuit:
Each resistor in a series circuit will cause a _______________ drop across itself:
Share your Results: