NCE PRACTICE EXAM

Ground wires attached to an unpainted frame surface make a positive contact and unless they become loose are least likely to cause a problem.

A is wrong because a loose or improperly mated connector can present a problem to the circuit and is a likely cause. B is wrong because wires that are nicked are exposed to the elements and will likely start to corrode. As the corrosion forces the insulation to expand, a lump will form in the wire. C is wrong because distorted electrical connector or wire is exposed to the elements and can likely become corroded. Electrical contact points and wires that have been overheated break down at the molecular level and corrosion starts within fractures in the structure.

The standard is 2.1 volts per cell and 2.1 times 6 is 12.6 volts. The other choices are incorrect on a fully charged auxiliary battery. Battery voltage needed to start the ICE engine is going to be over 12 volts, ideally would be 12.6 volts. When you crank the engine, the starter will draw current and drop the over 12v to 10.6 volts. During starting a healthy car battery voltage should be 10v or higher. Cold weather needs to be considered as this will decrease the voltage and increase the amount of power to turn over a cold engine. The voltage, when the engine is running, should be in the range of 13.5-14.7 volts.

A not start condition along with a stored DTC B2171 Inertia Input Switch Circuit open will take place after a frontal collision because the inertia cutout switch will trip in a collision. This is similar to Ford's inertia fuel cutout switch. A is incorrect because the engine will not crank and there is no ignition needed yet. C is incorrect because if the inverter were overheated there would be a message Stop Safely Now. D is incorrect because when you crank the engine the starter will draw current and drop to 10.6 volts and should still crank but may be slow. During starting a healthy car battery voltage should be 10v or higher.

When the brake on/off switch is defective, the vehicle would enter the POWER ON (Key On Engine Off) mode. Yet a failed brake on/off switch would not allow the hybrid engine control unit (ECU) to confirm that the brake pedal is applied, which is necessary for entering the READY TO DRIVE (Key On Engine Running) mode. It is possible that the ECU may not yet have recognized the lack of a feedback signal from the failed switch so a diagnostic trouble code (DTC) may not yet be stored.

B is wrong because when the high voltage safety plug is removed, the vehicle will enter the POWER ON (Key On Engine Off) mode, but would not enter the READY TO DRIVE (Key On Engine Running) mode. Also, with the safety plug removed the hybrid electric vehicle will store the DTC. C is wrong because with an empty fuel tank, the vehicle would enter the POWER ON (KOEO) mode and the READY TO DRIVE (KOER) modes as long as the high voltage battery maintains a sufficient state-of-charge. However, the internal combustion engine (ICE) would crank, but would not start due to the lack of fuel in the tank. This condition would set a DTC because the ICE did not start. D is wrong because a disconnected 12-volt auxiliary battery would prevent the vehicle from entering any operational power mode since the HEV ECU would not power up.

Technician B is right because checking the voltage drop between (+) positive and the starter terminal stud while the starter is cranking is a voltage drop check on cable connection resistance. Technician A is wrong because this will overload the fuse and could cause damage to the ohmmeter section of the DMM. The technician should use the voltmeter function of the DMM.

Technician B is correct because leather gloves should be worn over the high-voltage rubber gloves to protect the rubber gloves from damage from sharp objects. Technician A is incorrect because the gloves should be rated at least 1000 volts not 500 volts and class "0" by ANSI/ASTM.

High-voltage cables are identified by color of the plastic conduit and orange is used for 144 to 600 volts or higher. Blue or yellow are used for 42 volts, which are not a shock hazard but an arc will be maintained if a circuit is opened. Red is used for 12-volt circuits.

Technician A is correct because the PHEV shuts down the ICE whenever the vehicle comes to a full and complete stop when the AUTO STOP criteria has been met and vehicle should be silent in the electric operation mode. Tech B is incorrect because some driver input is required; such as: driver's seat belt is not buckled, driver's door is not closed, vehicle is on a steep grade, HVAC is set to full defrost mode at a high blower speed, HVAC set to MAX A/C, transmission is not in a forward gear, hood is open, or brake pedal is not pressed with sufficient pressure.

The MG serves as the starter motor for the ICE. Some Type-2 vehicles may be equipped with an auxiliary 12 V starter motor but the stem states that this vehicle does not have one. Power flow to the drive wheels can be provided by a split-pulley/steel belt continuously variable transmission, a conventional automatic transmission, or a standard transmission. A is incorrect because vehicle will enter READY TO DRIVE (KOER) mode, so voltage is available Equivalent to KOER - Key On/Engine Running. In this mode, the vehicle is ready to drive. The engine is running, or is OFF and ready to run if so commanded. The electric drive system is also ready for a drive command. B is incorrect because a Type-2 HEV does not use an MG1 or MG2 only an MG. C is incorrect because the CKP (crankshaft position) sensor is not need to crank the engine.

The MG1 serves as the starter motor for the ICE. A is incorrect because the vehicle will enter READY TO DRIVE (KOER) mode, so voltage is available Equivalent to KOER - Key On/Engine Running. In this mode, the vehicle is ready to drive. The engine is running, or is OFF and ready to run if so commanded. The electric drive system is also ready for a drive command. C is incorrect because the CKP (crankshaft position) sensor is not need to crank the engine. D is incorrect because a Type-3 HEV uses both an MG1 & MG2.