Question 1

Which of the following systems will require disabling the high voltage (HV) system during service?

Accepted Answer

The electric AC compressor is part of the vehicle's high voltage system in electric and hybrid vehicles. Working on this component requires disabling the high voltage system to ensure safety from electrical hazards.

Question 2

The hybrid vehicle control system can detect a high voltage leakage to ground by use of ________.

Accepted Answer

A ground fault monitor system is specifically designed to detect high voltage leakages to ground in hybrid vehicle control systems. This system monitors the integrity of the insulation and circuitry to ensure there are no unintended electrical paths to ground, which could be hazardous.

Question 3

All of the following will shut off the high voltage to components and circuits EXCEPT ________.

Accepted Answer

Opening the driver's door does not shut off the high voltage to components and circuits in a vehicle. Disconnecting the 12-volt auxiliary battery, removing the main fuse, relay, or HV plug, and turning the ignition off are actions that can disconnect or reduce the high voltage supply to various components and circuits in a vehicle, especially in hybrid or electric vehicles. However, simply opening the driver's door does not have any direct effect on the vehicle's high voltage system.

Question 4

A hybrid vehicle 12 volt battery is located under the hood. This will usually be a ________ type battery.

Accepted Answer

Hybrid vehicles typically use a flooded lead-acid battery for their 12-volt systems, which is commonly located under the hood.

Question 5

Servicing the base brakes on a hybrid vehicle requires the technician to ________.

Accepted Answer

Hybrid vehicles still use conventional brake systems (discs and pads) for stopping, in addition to regenerative braking systems. Therefore, servicing the base brakes, such as replacing the pads, is done similarly to non-hybrid vehicles.

Question 6

Some hybrid air conditioning systems use an electrically driven compressor that uses a special lubricant. What precaution should be taken when servicing these systems?

Accepted Answer

A dedicated recycling machine for the HEV is necessary to prevent contamination of the special lubricant used in the electrically driven compressor.

Question 7

What is the recommended location to store a HEV ignition key during service?

Accepted Answer

Storing the HEV ignition key in a lock box during service is recommended for safety and security reasons, ensuring that the vehicle cannot be inadvertently started or moved while being serviced.

Question 8

On a HEV that uses a "START" push button, what precaution should be taken when de-powering the vehicle?

Accepted Answer

The key fob should be at least 15 feet away from the vehicle to ensure it does not communicate with the vehicle's systems, preventing accidental activation or interference while the vehicle is being de-powered.

Question 9

How long can power be retained in the high voltage system once it has been disabled?

Accepted Answer

The high voltage system can retain power for up to 10 minutes after being disabled, as it takes time for the stored energy to dissipate safely.

Question 10

How should NiMH batteries be disposed of?

Accepted Answer

NiMH batteries, especially those used in vehicles, contain materials that can be harmful to the environment. Manufacturers often provide specific disposal instructions, including contact information such as an 800 number, to ensure these batteries are disposed of safely and in accordance with environmental regulations.

Question 11

How often should linesman's gloves be inspected by a qualified testing lab?

Accepted Answer

Linesman's gloves should be inspected by a qualified testing lab every six months to ensure their safety and effectiveness.

Question 12

Technician A says that all components in the high voltage battery box are completely insulated from the rest of the vehicle for safety. Technician B says that the high voltage battery box is located under the hood in some vehicles. Which technician is correct?

Accepted Answer

Technician A is correct because for safety reasons, components within the high voltage battery box are insulated to prevent electrical shocks and ensure that the high voltage does not affect other parts of the vehicle. Technician B is incorrect because while the high voltage battery can be located in various places in a vehicle, it is more commonly found under the vehicle or in the rear, not typically under the hood.

Question 13

The high voltage cables ________.

Accepted Answer

High voltage cables in vehicles are typically energized when the ignition switch is in the "on" position to power the electric motor or motors. Additionally, these cables are universally color-coded in orange to indicate their high voltage nature and caution handlers.

Question 14

Technician A says that when a hybrid electric vehicle must remain in the shop for over a month, the battery should be charged by running the vehicle if possible. Technician B says that if the battery unit must be removed, it should be handled with PPE and always tested for voltage and treated with care. Which technician is correct?

Accepted Answer

Both technicians are correct. Technician A is correct because hybrid vehicle batteries can discharge over time, and running the vehicle can help maintain the battery's charge. Technician B is correct because safety precautions, including the use of Personal Protective Equipment (PPE) and voltage testing, are essential when handling hybrid vehicle batteries due to their high voltage and potential hazards.

Question 15

Technician A says that the high voltage cables may be repaired if damaged while lifting on a vehicle hoist. Technician B says that a paint oven does not get hot enough to damage high voltage cables or other hybrid components. Which technician is correct?

Accepted Answer

High voltage cables in hybrid and electric vehicles are typically not repairable due to safety concerns; they usually need to be replaced if damaged. Paint ovens can indeed get hot enough to damage high voltage cables and other hybrid components, so it's important to be cautious about exposing these vehicles to high temperatures.

Question 16

What is TRUE regarding protective gloves worn during HV system service?

Accepted Answer

Both statements are true regarding protective gloves worn during HV (High Voltage) system service. Leather gloves are indeed worn over rubber gloves to protect the rubber from physical damage, and rubber gloves should be checked for leaks before each use to ensure they provide the necessary insulation from electrical hazards.

Question 17

Technician A says that CAT I meter leads may be used to test HV system components as long as the DMM itself is rated CAT III. Technician B says that CAT IV test leads are clamp-on inductive type leads. Which technician is correct?

Accepted Answer

The answer of Technician A says that CAT I meter...

Question 18

Technician A says that DMMs are assigned CAT ratings based on voltage capacity alone. Technician B says that DMMs are rated according to their ability to handle potential electrical energy. Which technician is correct?

Accepted Answer

Technician B is correct because DMMs (Digital Multimeters) are rated not just based on voltage capacity but also according to their ability to handle potential electrical energy, which includes factors like transient overvoltages and the environment in which they are used. This is why CAT (Category) ratings are important, as they provide information on the meter's ability to withstand these conditions.

Question 19

Technician A says that the that HV battery is grounded to the vehicle chassis. Technician B says that the HV battery and cables are completely insulated and isolated from the rest of the vehicle. Which technician is correct?

Accepted Answer

Technician B is correct because in electric and hybrid vehicles, the high voltage (HV) battery and its cables are designed to be completely insulated and isolated from the vehicle's chassis to prevent electrical hazards.

Question 20

Technician A says that a completely assembled electric motor is not likely to produce injury by electrical shock. Technician B says that turning off the ignition on an HEV causes the system main relay to disable the high voltage system. Which technician is correct?

Accepted Answer

Technician A is correct because a completely assembled electric motor, especially in the context of automotive applications, is designed with safety in mind and is unlikely to expose live electrical parts that could cause a shock. Technician B is also correct because turning off the ignition in a Hybrid Electric Vehicle (HEV) typically causes the system's main relay to open, which isolates the high voltage battery from the rest of the vehicle's electrical system, effectively disabling the high voltage system to ensure safety.

Quiz 90: Hybrid Safety and Service Procedures