Practice Test Geeks(EVT) Certified Electric Vehicle Technician Practice Test
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EVT Thermal Management & Cooling Systems Flashcards

6 cards from real EVT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 6 EVT Thermal Management & Cooling Systems flashcards as text

  1. Why is battery pre-conditioning important before DC fast charging in cold weather?

    Answer: It warms the cells to reduce internal resistance and enable acceptance of high charge currents safely

    Cold cells have high internal resistance and risk lithium plating if charged at high rates; pre-conditioning brings cells to optimal temperature so the BMS can allow full DC fast charge current.

  2. What type of pump is most commonly used to circulate coolant through an EV battery cooling loop?

    Answer: Electric brushless DC centrifugal pump

    EV cooling systems use electric brushless DC centrifugal pumps because they can be controlled independently of engine speed, operate at variable flow rates, and function when the vehicle is stationary.

  3. An EV's cabin heater uses a Positive Temperature Coefficient (PTC) heating element. What is a key safety characteristic of PTC heaters?

    Answer: They increase resistance as they heat up, self-limiting maximum temperature and preventing overheating

    PTC elements increase resistance as temperature rises, reducing current draw automatically and making them inherently self-regulating against overheating.

  4. During regenerative braking, excess heat is generated in which component that the thermal management system must dissipate?

    Answer: Power electronics (inverter/motor controller) and motor stator windings

    High regenerative braking current flows through the inverter IGBTs and motor windings, generating significant heat that the inverter and motor cooling loops must remove.

  5. A technician is pressure-testing a repaired battery cooling jacket. What maximum test pressure is typically used to avoid damaging the jacket while verifying integrity?

    Answer: 15–30 PSI

    Battery cooling jackets are typically tested at 15–30 PSI to confirm seal integrity; higher pressures can permanently deform the thin aluminum plates used in most cooling plate designs.

  6. What does 'glycol degradation' in an EV coolant system indicate, and what is the corrective action?

    Answer: Coolant has become acidic from additive depletion, requiring a flush and fill with fresh approved coolant

    Degraded glycol loses its corrosion inhibitors and becomes acidic, attacking aluminum cooling plates and seals; the system must be flushed and refilled with fresh OEM-approved coolant.