ASE A6 Electrical Electronics Practice Test

Engine cooling fan circuit.

8. The engine’s electric cooling fan in the illustration operates continuously when the ignition is switched ON, even when cold. Which of the following would result in this continuous fan motor operation?

  • A. Excessive resistance at point A of the system.
  • B. An open at point B in the system.
  • C. A short to ground at point C in the system.
  • D. An open at point D of the system.

8.

Engine cooling fan circuit answers.

Answer A is wrong. This is the engine coolant temperature sensor circuit. Resistance in this circuit will corrupt the signal from the sensor.

Answer B is wrong. An open at point B results in no fan operation. This is because the control module is unable to control (ground) the open circuit.

Answer C is correct. A short to ground at point C activates the relay causing the fan to run when the ignition is switched on, even when the engine is cold.

Answer D is wrong. An open at point D will prevent fan motor operation.