Electrical (A6)Question 79 of 120
The gauge or module that displays engine coolant temperature relies on a sensor whose resistance:
a.Changes with temperature (a thermistor)
b.Stays constant regardless of temperature
c.Only works above 200 degrees
d.Produces AC voltage
Explanation
Most coolant temperature sensors are thermistors whose resistance falls as temperature rises (negative temperature coefficient). The computer or gauge interprets this changing resistance as temperature. A faulty sensor can cause inaccurate readings and driveability or fan-control problems.
Practice all 120 questions free — no signup required.
Related questions on this topic
- Technician A says a diode allows current to flow in only one direction. Technician B says alternators use diodes to rectify AC into DC. Who is correct?
- Excessive AC ripple voltage measured at the battery with the engine running usually indicates:
- Technician A says a relay lets a small control current switch a larger load. Technician B says relays protect switches and allow smaller control wiring. Who is correct?
- Dim headlights that brighten when engine rpm increases most likely indicate:
- A voltmeter is connected how, relative to the component being tested?
- A circuit has 12 volts applied and draws 2 amps. Its total resistance is:
Last reviewed: · editorial process
PrepPass Editorial Team · Verified against ASE Automobile Certification Series (A1–A8) · How we review