- Laptops
- Laptop
Back Cover was Opened
ASUS Back Cover was Opened on laptop: bottom cover alert
Risk level
Low
Usually safe to check without specialist tools.
Urgency
Medium
Quick answer
On the ASUS or ROG logo screen you see a Back Cover was Opened warning: the Ambient Light Sensor recorded that the bottom cover was removed. Press the power button to shut down and power back on, or press Ctrl+Alt+Del to restart into Windows.
Safety first
Stop and check this first
- On ASUS notebooks with an Ambient Light Sensor (ALS), removing the back cover exposes the sensor to light and automatically cuts power for protection: do not open the bottom cover yourself or try to bypass the sensor.
- If the laptop runs memory training after an EC reset or hardware work, keep the AC adapter plugged in and do not force a shutdown during the 5 to 10 minute wait.
Safe checks you can perform
- Clear the prompt with the power button or Ctrl + Alt + Del
- Wait 5 to 10 minutes if memory or the battery was touched
- Disconnect external devices and run a 40-second EC reset
- Enter BIOS with F2 and restore BIOS default settings
Leave these tasks to a qualified professional
- Do not attempt this professional task: BIOS update via EZ Flash and internal hardware verification
- Do not attempt this professional task: Bottom cover fit and Ambient Light Sensor (ALS) inspection
What a technician must be able to justify
Technician visit
These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.
These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.
BIOS update via EZ Flash and internal hardware verification
What they doWhen the notebook remains stuck on the logo screen after an upgrade or prior service, the technician verifies installed memory/storage and updates the BIOS using EZ Flash.
They must show youthe updated BIOS version and the laptop booting into Windows without hanging on the logo.
In writingthe BIOS version installed, the internal components checked, and the ASUS service case number.
Bottom cover fit and Ambient Light Sensor (ALS) inspection
What they doIf Back Cover was Opened keeps appearing on every boot without the cover being removed, an ASUS service center inspects the bottom chassis fit and the ALS protection circuit.
They must show youthe bottom cover properly seated and consecutive startups passing the ASUS or ROG logo without the warning.
In writingthe Back Cover was Opened message, the ALS and chassis inspection findings, and the repair warranty.
Before accepting a part or repair
Nothing has been shown yet. Do not accept a part swap based on the code alone.
Follow these steps
Note: Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.
Clear the prompt with the power button or Ctrl + Alt + Del
- Who:
- you, with the Back Cover was Opened prompt on the ASUS or ROG logo screen.
- How:
- check from the outside that the bottom cover sits flush and closed. Then, as Answer 1 of FAQ 1042613 states, press the power button to shut down the laptop and press it again to start up, or press Ctrl + Alt + Del on the keyboard to restart directly into Windows.
- Result that matters:
- clearing the one-time ALS reminder so the laptop proceeds into Windows normally.
- If Windows loads and the warning does not return on the next boot:
- the ALS reminder has been cleared.
- If the laptop stays stuck on the ASUS or ROG logo screen:
- continue with the next check without removing the bottom cover.
- Evidence to keep:
- a photo of the Back Cover was Opened screen and a note of whether the bottom cover was recently opened.
Evidence: Troubleshooting - Stuck on ASUS/ROG Logo Screen During Boot
Wait 5 to 10 minutes if memory or the battery was touched
- Who:
- you, with the ASUS charger connected after closing the bottom cover.
- How:
- if the battery connector was disconnected, memory modules were replaced, the BIOS was updated, or an EC/RTC reset was run, plug in the AC adapter and wait 5 to 10 minutes without forcing a shutdown while full memory training completes, as Answer 2 of FAQ 1042613 advises.
- Result that matters:
- allowing memory training to finish so the system can leave the logo screen on its own.
- If it moves past the logo within 10 minutes:
- let Windows finish loading normally.
- If it remains stuck past 10 minutes:
- disconnect external peripherals and perform an EC reset.
- Evidence to keep:
- which hardware or BIOS action happened beforehand and how long you waited on AC power.
Evidence: Troubleshooting - Stuck on ASUS/ROG Logo Screen During Boot
Disconnect external devices and run a 40-second EC reset
- Who:
- you, with the laptop powered off and closed.
- How:
- unplug all external devices including mice, keyboards, USB drives, optical discs, card reader adapters, and external monitors. With the AC adapter connected, hold the power button for 40 seconds (or on 20-second models, release after the LED flashes rapidly for 3 to 5 seconds after 15 seconds, per FAQ 1050239), then turn the laptop on.
- Result that matters:
- resetting the Embedded Controller (EC) and Real-Time Clock (RTC) hardware to its default state.
- If it boots into Windows after the EC reset (allowing a few minutes for memory training):
- monitor the next startups.
- If it still freezes on the logo screen:
- enter BIOS setup with F2 to restore defaults.
- Evidence to keep:
- the list of unplugged peripherals and confirmation of the EC reset.
Evidence: How to Reset Embedded Controller (EC Reset), Real-Time Clock (RTC), and Hard Reset · Troubleshooting - Stuck on ASUS/ROG Logo Screen During Boot
Enter BIOS with F2 and restore BIOS default settings
- Who:
- you, starting from a powered-off laptop.
- How:
- shut down the laptop, press and hold the F2 key, press the power button, and release F2 once the BIOS setup screen appears. Restore the default BIOS settings as directed in FAQ 1042613, save, and restart.
- Result that matters:
- ruling out a BIOS configuration hang after the ALS power-off event.
- If the laptop boots into Windows cleanly:
- keep an eye on the next few power-ons.
- If the Back Cover was Opened warning keeps coming back or the logo stays frozen:
- contact an ASUS service center.
- Evidence to keep:
- a photo of the BIOS version in setup and the result after restoring defaults.
Evidence: Troubleshooting - Stuck on ASUS/ROG Logo Screen During Boot
Still not solved
If the error persists, stop here. See what the technician must do and show you.
Where this code applies
A code is meaningful only inside the right product and version context.
Primary scope
- System
- Laptops
- Brand
- ASUS
- Product type
- Laptop
Known code variants
- advertencia La tapa trasera fue abierta ASUS
- Ambient Light Sensor ALS ASUS laptop
- ASUS Back Cover was Opened
- ASUS logo screen Back Cover was Opened
- ASUS ROG logo Back Cover was Opened
- atascado en logo ASUS tapa trasera
- Back Cover was Opened
- La tapa trasera fue abierta
- ROG Back Cover was Opened warning
- sensor de luz ambiental ALS ASUS
What it means
In ASUS's troubleshooting guide for devices stuck on the ASUS or ROG logo screen during boot (FAQ 1042613, covering Notebook, Desktop, All-in-One PC, and Gaming Handheld), Q&A Question 1 explains that certain notebooks with an Ambient Light Sensor (ALS) cut power automatically when the back cover is removed and exposed to light, then show this reminder the first time you power on after reattaching the cover. Other models may differ, and the warning alone never proves a part is faulty.
Warnings and stop conditions
- Highsource verified
On ASUS notebooks with an Ambient Light Sensor (ALS), removing the back cover exposes the sensor to light and automatically cuts power for protection: do not open the bottom cover yourself or try to bypass the sensor.
Evidence: Troubleshooting - Stuck on ASUS/ROG Logo Screen During Boot
- Mediumsource verified
If the laptop runs memory training after an EC reset or hardware work, keep the AC adapter plugged in and do not force a shutdown during the 5 to 10 minute wait.
Evidence: Troubleshooting - Stuck on ASUS/ROG Logo Screen During Boot
Symptoms and causes
Probable causes · in order
- Bottom cover removal recorded by the Ambient Light Sensor (ALS)Common
ASUS explains that the ALS power-off protection cuts system power when exposed to light and reminds you on the first boot after the bottom cover is reattached.
Evidence: Troubleshooting - Stuck on ASUS/ROG Logo Screen During Boot
- Memory training after a battery disconnect or memory changePossible
If opening the cover also involved disconnecting the battery, swapping memory modules, or updating the BIOS, Question 2 of FAQ 1042613 notes that the next boot runs memory training for 5 to 10 minutes.
Evidence: Troubleshooting - Stuck on ASUS/ROG Logo Screen During Boot
- External peripheral or BIOS setting holding the logo screenLess common
If the laptop stays frozen on the ASUS or ROG logo even after clearing the prompt, FAQ 1042613 points to connected external devices or BIOS state needing an EC reset or BIOS defaults.
Evidence: How to Reset Embedded Controller (EC Reset), Real-Time Clock (RTC), and Hard Reset · Troubleshooting - Stuck on ASUS/ROG Logo Screen During Boot
Virtual technician
Does Back Cover was Opened still appear after these checks?
Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.
Sources and technical references
- 1
How to Reset Embedded Controller (EC Reset), Real-Time Clock (RTC), and Hard Reset
ASUS · 2026 · official_doc
- 2
- 3
Troubleshooting - Stuck on ASUS/ROG Logo Screen During Boot
ASUS · 2026 · official_doc
- 4
Solución de problemas: Atascado en la pantalla del logo de ASUS/ROG durante el arranque
ASUS · 2026 · official_doc
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