Examkin

Question

Difficulty: MediumLaptop Power Systems and Battery Management

A technician is performing a battery calibration procedure on a corporate laptop to resolve inaccurate battery percentage reporting in the operating system. Place the steps of the battery calibration process in the correct order from first to last.

  1. 1Connect the AC power adapter and charge the laptop battery continuously to 100% capacity.
  2. 2Adjust OS power management settings to prevent the system from entering sleep or hibernation on low battery.
  3. 3Disconnect the AC power adapter and run the laptop on battery power until it drains completely and turns off.
  4. 4Leave the laptop unpowered for at least 30 minutes to allow the battery to cool down.
  5. 5Reconnect the AC adapter and recharge the laptop uninterrupted back to 100% without powering on the OS.

Answer

The correct calibration sequence begins with fully charging the battery to 100%, configuring power plan settings to prevent premature system sleep/hibernation, discharging the battery completely until shutdown, allowing the system to rest and cool down, and finally recharging the battery continuously back to 100% uninterrupted.
Battery calibration recalibrates the internal fuel gauge IC by forcing a full top-to-bottom charge cycle. The system must first be charged to 100%, OS power-saving limits disabled so it drains fully to hardware shutdown, rested to cool down, and uninterruptedly recharged to 100%.

Step-by-Step Solution

1
Fully charge the laptop battery to 100%.
The top-end charge capacity threshold is registered by the power controller.
Establishes a known full-charge state before starting the full discharge cycle.
2
Disable automatic low-battery power actions (sleep/hibernate).
The operating system will not initiate automatic shutdown before true battery exhaustion.
Ensures the laptop runs until the hardware battery protection circuit cuts power at genuine zero state.
3
Unplug AC power and drain the battery until system power cuts off.
The battery registers its full discharge cycle threshold.
Measures the actual remaining discharge capacity against original design limits.
4
Allow the unpowered system to cool for 30 minutes.
Internal cell temperatures return to ambient levels.
Prevents thermal skewing of voltage measurements during the final charge sequence.
5
Plug in AC power and charge continuously back to 100%.
The fuel gauge IC syncs its full charge capacity metric with OS power diagnostics.
Completes the recalibration loop by establishing calibrated 0% and 100% thresholds.

Key Concept

Laptop Smart Battery Fuel Gauge Recalibration
Rate this question

Topics

Laptop Power Systems and Battery Management

More questions from this topic