MacBook Won't Turn On: Intel vs Apple Silicon Diagnosis Guide

MacBook Won’t Turn On: Where to Start

Before assuming the worst, it helps to know which generation of Mac you’re dealing with. Intel MacBooks (pre-2020) and Apple Silicon MacBooks (M1, M2, M3 — 2020 onwards) have different power management architectures, different reset procedures, and fail in different ways.

This guide walks through both.

First: Which MacBook Do You Have?

If you’re unsure whether your MacBook uses Intel or Apple Silicon:

• Apple Silicon (M1/M2/M3): Any MacBook Air or MacBook Pro bought from late 2020 onwards. The packaging or the original receipt will say M1, M2, or M3.
• Intel: MacBook Pro and MacBook Air models from 2019 and earlier are all Intel. Some 2020 MacBook Pros are also Intel (the last Intel MacBook Pro was released in late 2020).

If the Mac is off and you can’t check, the physical clues are: Apple Silicon MacBooks have no fan noise on the MacBook Air (M1/M2/M3 Air is fanless), and all Apple Silicon MacBooks charge via USB-C only with no MagSafe on the earliest M1 models (MagSafe returned with M2).

Symptoms and What They Mean

The Mac appears completely dead — no light, no sound, no response

This is the most alarming presentation, but not always the most serious.

On both Intel and Apple Silicon:

• Check the charging cable and adapter. A failed USB-C cable or charger is the single most common reason for a MacBook appearing dead. Try a known-good cable and adapter if you have one.
• Check the charging port for debris. Fluff and pocket lint in USB-C ports is extremely common and prevents proper contact.
• If the MacBook has sat unused for weeks or months, the battery may be completely discharged. Leave it on charge for 30–60 minutes before pressing the power button.

The Mac shows a charging light or indicator but won’t boot

This means power is reaching the machine but it isn’t completing startup. The cause could be:

• A corrupted macOS installation
• Failed storage (the SSD has died or become unreadable)
• A logic board fault preventing the boot process from completing
• A firmware issue (more common on Intel)

The Mac starts to boot — fan spins or chime sounds — then stops

On Intel Macs: A brief startup attempt followed by shutdown often points to a RAM fault, a GPU issue, or a power delivery problem on the logic board. Intel MacBooks with the 2011–2013 discrete GPU are particularly prone to GPU failure causing exactly this symptom.

On Apple Silicon Macs: The M-series chips handle power management very differently. A partial boot attempt that stops is more likely to indicate a software/firmware issue or a storage fault than a hardware component failure, because Apple Silicon integrates CPU, GPU, RAM, and storage controller on the same chip — there are fewer discrete components that can individually fail.

Reset Procedures: Intel vs Apple Silicon

The reset procedures are completely different between generations. Using the wrong one wastes time and doesn’t help.

Intel MacBook: SMC Reset

The System Management Controller (SMC) handles power, battery, fans, and sleep/wake on Intel Macs. A corrupted SMC can cause exactly the symptoms above.

For MacBooks with a T2 chip (2018–2020 Intel models):

1. Shut down (or attempt to if it won’t stay on)
2. Press and hold: Left Shift + Left Control + Left Option + Power button simultaneously for 10 seconds
3. Release all keys
4. Press the power button normally to start up

For older Intel MacBooks (pre-2018, without T2):

1. Shut down
2. Press and hold: Left Shift + Left Control + Left Option + Power button simultaneously for 10 seconds
3. Release, then press Power normally

After an SMC reset, the Mac should start up normally if the SMC was the cause. If it doesn’t, the fault is elsewhere.

Intel MacBook: NVRAM/PRAM Reset

NVRAM stores startup disk selection, display resolution, and speaker volume. A corrupted NVRAM can sometimes prevent startup.

1. Restart (or power on) the Mac
2. Immediately hold: Command + Option + P + R
3. Hold for about 20 seconds — on older Macs you’ll hear the startup chime twice; on T2 Macs just hold for 20 seconds
4. Release and let it boot normally

Apple Silicon MacBook: No SMC or NVRAM Reset

Apple Silicon Macs do not have an SMC or NVRAM in the Intel sense. These reset procedures do not apply.

For an Apple Silicon Mac that won’t boot, the equivalent starting point is:

Force restart: Press and hold the power button for 10 seconds until the Mac shuts off. Then press the power button once to restart.

If that doesn’t work — Recovery Mode: Press and hold the power button until you see “Loading startup options”. From there you can run First Aid on the storage, reinstall macOS, or restore from a Time Machine backup.

If Recovery Mode itself doesn’t load, the fault is likely hardware-level — storage or logic board.

Apple Silicon-Specific Faults

“No bootable device” or “?” on startup

This means the Mac cannot find macOS on the internal storage. On Apple Silicon this usually means:

• macOS has become corrupted and needs reinstalling via Recovery Mode
• The SSD has failed (less common but possible)
• The storage chip has failed at a component level (requires specialist repair)

On M1 and later, the SSD is soldered directly to the logic board. This means an SSD failure often means a logic board repair or replacement, not a simple drive swap. data recovery from a failed Apple Silicon Mac is significantly more complex than from an Intel Mac with a removable SSD.

Activation Lock preventing startup

If you see a lock icon and a message about Activation Lock on startup, this isn’t a hardware fault — the Mac is linked to an Apple ID and cannot be activated without the credentials. This is common on secondhand Macs where the previous owner didn’t sign out of iCloud.

Intel-Specific Faults

MagSafe LED behaviour

If your Intel MacBook has MagSafe charging (most models pre-2016 and the 2021+ M2 models), the LED provides diagnostic information:

• Amber/orange: Charging normally
• Green: Fully charged
• No light: Cable not making contact, cable fault, or no power reaching the machine
• Flashing orange: Battery fault

A MagSafe that never shows any light despite multiple cables usually points to a board-level power fault — often a blown fuse or failed charging IC on the logic board.

T2 chip issues (2018–2020 Intel models)

The T2 security chip manages startup security, encrypted storage, and the Touch ID on these models. A T2 chip fault can prevent startup entirely. T2 issues are not user-recoverable — they require specialist diagnostic tools to identify and, in some cases, component-level repair.

When to Bring It In

You’ve worked through the steps above and:

• The Mac still won’t power on at all
• It attempts to start but stops before reaching the login screen
• Recovery Mode is inaccessible
• You’re concerned about data on the drive

At this point, continuing to attempt resets risks nothing, but is unlikely to resolve a hardware-level fault. A MacBook repair workshop diagnosis will identify whether the fault is storage, logic board, power circuit, or firmware — and give you a clear quote before any work begins.

If you have data you haven’t backed up, tell us before we start. If the storage is accessible, we’ll prioritise getting a backup before attempting any repairs.

Book a diagnosis at our Putney workshop or call 020 7610 0500. We cover MacBook repairs across South West London — contact us to arrange a convenient time.