Apple MacBook Pro F90 Error Code Fix Guide

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What This Error Means

F90 on a MacBook Pro is a fan / cooling system error. Translation: the Mac thinks at least one fan isn’t spinning right or the cooling system can’t keep temps under control.

What you see: fans blasting at full speed, random slowdowns or shutdowns, and F90 (often in diagnostics or a third‑party tool) complaining about fan failure or abnormal RPM.

Official Fix

Apple’s playbook is simple: assume a hardware cooling fault and push you to a service center. Here’s the clean, by‑the‑book route.

  • 1. Power it down properly
    • Shut down macOS (Apple menu > Shut Down).
    • Unplug the charger and disconnect everything else (USB, hubs, displays).
  • 2. Basic vent check
    • Look at the rear hinge area and side vents.
    • Remove any snap‑on case or skin blocking airflow.
    • Blow out loose dust from vents with short bursts of compressed air (from the outside only).
  • 3. Reset the SMC (System Management Controller) (Intel MacBook Pro only)
    • With it shut down, hold Shift + Control + Option (left side) + Power for 10 seconds.
    • Release, then press Power again to turn it on.
    • If you’re on Apple Silicon (M1/M2/M3), a full shutdown and 30 seconds unplugged is the SMC equivalent.
  • 4. Run Apple Diagnostics
    • Shut down again.
    • Hold D while powering on (or Option + D for internet diagnostics).
    • Let the test run. If it flags a fan or cooling error again, that’s Apple’s green light for hardware replacement.
  • 5. Update macOS and firmware
    • Boot back into macOS.
    • Go to System Settings > General > Software Update.
    • Install everything offered. Some models calm fan logic with firmware tweaks.
  • 6. Official service path
    • If F90 or fan‑related diagnostics persist, Apple’s official move is part swap, not repair.
    • For older MacBook Pros: they’ll usually replace the fan assembly for that side (or both).
    • For newer models where fans are tied closely into the main board, you may get quoted for a full top case or even logic board replacement.
    • Cost at Apple/AASP typically: US$150–$350 for fan/top case work, up to $500–$900+ if they jump straight to logic board.

Bottom line: official route = diagnostics, then part replacement (fan or board), no board‑level fiddling, no cleaning beyond basic dusting.

The Technician’s Trick

Here’s what a bench tech actually does before dropping big money on boards.

  • 1. Back up like it might die
    • If it still boots, run a full Time Machine or Clone backup now.
    • Any cooling fault can turn into random power‑offs. Don’t trust it.
  • 2. Open it and check the fans for real
    • Shut down, flip it over, remove the bottom cover (usually P5 pentalobe screws).
    • Look at the fans: any broken blades, dust packed in the vents, or signs of liquid?
    • Spin each fan gently with a finger. It should spin freely and stop smoothly. Grinding or stiffness = bad fan.
  • 3. Reseat fan connectors
    • Unplug each fan connector from the board carefully, then plug it back in firmly.
    • A half‑seated connector can throw F90 even if the fan is fine.
    • Check for corrosion (green/white gunk) around the connector. That screams liquid damage.
  • 4. Proper deep clean
    • Hold the fan blades in place and blow dust out of the heatsink fins with compressed air.
    • Brush off caked dust from the fan edges and exhaust slots.
    • Do not spin fans with air like a turbine; that can kill the bearings.
  • 5. Thermal paste refresh (for hot/older machines)
    • On 5+ year old Intel Pros running hot, many techs pull the heatsink and replace the thermal paste.
    • Fresh quality paste can drop temps and keep the Mac out of panic mode, clearing borderline F90 events.
    • If you’re not comfortable pulling the heatsink, skip this and just replace bad fans.
  • 6. Test with fan monitoring
    • Reassemble, boot, and use any reputable macOS fan/RPM monitor.
    • You want both fans reporting normal RPM ranges and responding when the system heats up.
    • No RPM on one side, or zero change under load, means that fan or its circuit is toast.
  • 7. When we call it a logic board fault
    • New fans installed and seated, but F90/fan errors stay? Then the fan driver or sensor line on the logic board is likely blown.
    • Shop techs may do component‑level repair, but consumers usually choose between living with loud fans or replacing the board.

Insider rule: try fans and a serious clean before paying for a logic board. Fans fail way more often than the board circuitry that drives them.

Is It Worth Fixing? (The Financial Verdict)

  • ✅ Fix: F90 on a MacBook Pro less than 6–7 years old, no liquid damage, fans clearly dirty or noisy. Fan + clean job is usually cheap and worth it.
  • ⚠️ Debatable: Mid‑age Intel Pro with high battery cycles, some cosmetic wear, and a quote that involves fan + top case work in the $250–$400 range.
  • ❌ Replace: Very old Intel MacBook Pro, liquid damage on the board, or any repair where they’re quoting $500+ for a logic board just to solve F90.

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