Technician A says that vehicles with electronic returnless fuel systems use pulse width modulation to power the fuel pump and maintain fuel pressure. Technician B says that the electronic returnless fuel system uses a contact switch to control the fuel pump. Which technician is correct?
A) Technician A only
B) Technician B only
C) Both technicians A and B
D) Neither technician A nor B

Question

Quizplus · Accepted Answer

Technician A is correct that electronic returnless fuel systems use pulse width modulation to power the fuel pump and maintain fuel pressure. Technician B is incorrect that the system uses a contact switch to control the fuel pump. Electronic returnless fuel systems use a fuel pressure sensor to monitor the fuel pressure and adjust the power to the fuel pump accordingly.

Technician a Says That Vehicles with Electronic Returnless Fuel Systems