What Does “Unknown Part” Mean on an iPhone Before You Sell It?

What Does “Unknown Part” Mean on an iPhone Before You Sell It?

An “Unknown Part” message on an iPhone means Apple cannot verify a component in the normal way. It may appear because the part is not genuine, is not working as expected, has not been correctly verified after a repair, or has been modified. Importantly, “Unknown” does not automatically mean “fake”.

If you are thinking about selling your iPhone, the message is worth checking because Apple says an Unknown part may affect the trade-in value of the device.

Before getting a valuation, go to:

Settings → General → About → Parts and Service History

Then check which component carries the warning and test that part of the phone properly.

Quick answer: Yes, you can still sell an iPhone that shows an Unknown Part message. However, the warning can affect its resale value or condition grade, especially if the affected component also has a fault.

What does “Unknown Part” actually mean on an iPhone?

Apple records information about certain repairs under Parts and Service History.

Depending on the iPhone model, component and repair, you may see labels such as:

• Genuine
• Used
• Unknown
• Unverified
• Finish Repair

A replaced component is not automatically a bad component.

Modern iPhones can recognise genuine repairs and, on supported models, genuine Apple components that were previously installed in another iPhone.

The problem arises when Apple cannot verify a component normally or when part of the repair process has not been completed correctly.

Why does an iPhone say Unknown Part?

According to Apple's current iPhone Parts and Service History guidance, an Unknown message can appear when a replacement part:

• is not a genuine Apple part
• is not functioning as expected
• has not been verified and linked correctly to the iPhone after repair
• has been modified or cannot otherwise be verified
• In other words, Unknown Part is a status message, not a complete diagnosis.

For example, if an iPhone says Unknown beside Display, that does not prove somebody fitted a counterfeit screen.

A non-genuine screen is one possibility. However, the message could also relate to a verification issue, an incomplete repair or a fault with the component.

Does Unknown Part mean my iPhone has a fake component?

No. An Unknown Part message does not automatically mean the component is fake.

This distinction matters when you sell the phone.

If you know that a repairer fitted a third-party screen, you can describe it as a third-party replacement.

However, if you do not know the repair history, it is more accurate to say:

“The iPhone shows Unknown beside Display in Parts and Service History.”

That tells the buyer exactly what the phone reports without making a stronger claim than the evidence supports.

Apple itself lists several possible causes for an Unknown status, so treating every Unknown component as counterfeit would be misleading.

Can you sell an iPhone with an Unknown Part message?

Yes. An iPhone showing Unknown Part can still have resale value.

The more important question is how much the warning affects the handset's condition and value.

A buyer will usually care about two things:

What does the iPhone report about the component?

Does that component actually work properly?

Imagine two iPhones that both show:

Display — Unknown

The first phone has:

• smooth touch response
• normal brightness
• accurate colours
• working Face ID
• no flickering
• no visible display defects
• The second phone has:
• intermittent touch problems
• noticeable flickering
• poor colour reproduction
• unreliable Face ID
• occasional missed touches

Both phones carry the same basic warning.

However, they present very different levels of risk to a buyer.

That is why an Unknown Part message should form part of the overall condition assessment rather than automatically making the phone worthless.

If your handset has other physical or functional damage as well, read our guide to pricing a broken iPhone in the UK.

Does an Unknown Part message reduce iPhone resale value?

It can, but there is no universal percentage reduction.

Apple explicitly says an Unknown part might affect trade-in value.

The actual effect depends on factors such as:

1. the iPhone model
2. which component carries the warning
3. whether the component works properly
4. the phone's cosmetic condition
5. battery health
6. other functional faults
7. the likely cost of another repair
8. the buyer's grading criteria

For example, an uncertain display repair on a recent Pro model may present more financial risk than the same issue on a much older handset.

Similarly, an Unknown battery creates different concerns from an Unknown camera.

Repair history can affect your phone's grade

Repair history is not simply an obscure message hidden in Settings.

Sell My iPhone's current Terms and Conditions make component originality and warnings relating to non-genuine Apple battery, display or camera parts relevant to grading.

However, remember that Apple's Unknown label does not itself prove a component is non-genuine.

The practical lesson is straightforward:

• a pristine exterior does not necessarily mean the handset qualifies for the highest grade
• internal condition matters
• battery health matters
• functional faults matter
• component and repair history can matter too

Where do you find Parts and Service History on an iPhone?

Checking takes less than a minute.

• Open Settings.
• Tap General.
• Tap About.
• Scroll down.
• Look for Parts and Service History.

Check the description shown beside each listed component.

If the section contains repair information, take a screenshot before wiping the handset.

That gives you a useful record if you later need to confirm what the phone displayed before sale.

While you are in Settings, confirm the exact model and storage capacity too.

If you are unsure, use our guide to checking your iPhone model and storage before selling.

Choosing the wrong model or storage capacity can produce an inaccurate valuation before repair history is even considered.

Which iPhones show Parts and Service History?

The information available depends on the iPhone model.

Apple also states that if the same component has been serviced more than once, Parts and Service History shows only the most recent service.

You can check the latest model-specific information on Apple's Parts and Service History page.

Genuine, Used, Unknown and Finish Repair: what is the difference?

Apple's repair terminology has become more detailed over time.

A Used part is not the same as an Unknown part

Apple has expanded support for genuine components that have previously been installed in another compatible iPhone.

Therefore:

1. Used does not mean fake
2. Used does not mean Unknown
3. a genuine replacement part does not have to be brand new
4. repair history does not automatically make a phone faulty

Apple explained this approach when it announced its move towards supporting used genuine Apple parts in iPhone repairs.

As iPhones remain in use for longer and change hands several times, genuine repair history is likely to become increasingly normal.

What does an Unknown display mean before selling an iPhone?

Displays are particularly important because screen replacements are common.

Apple says an Unknown display message may appear when the display:

• is not a genuine Apple part
• does not function as expected
• has not been correctly verified and linked after repair
• has been modified or cannot otherwise be verified

Apple also explains that non-genuine displays can sometimes cause problems involving:

• touch response
• brightness
• colour performance
• ambient-light behaviour
• True Tone
• unintended touches

You can read the technical detail in Apple's guidance on genuine iPhone displays.

Test more than whether the screen switches on

A replacement display can look perfectly normal at first glance while still having problems.

Before selling, check:

• touch response across the entire screen
• manual brightness
• automatic brightness
• colour consistency
• True Tone, where available
• screen flickering
• dead areas
• unintended touches
• Face ID

A photograph of a clean-looking screen tells a buyer very little about how well the display actually works.

What does an Unknown battery mean?

An Unknown battery and poor battery health are not the same thing.

Battery health concerns the battery's capacity and condition.

Unknown Part concerns the component's verification or repair status.

An iPhone could therefore have:

1. a healthy battery percentage but an Unknown battery message
2. a verified battery with poor maximum capacity
3. an Unknown warning and poor battery health at the same time

Check both before requesting a valuation.

Sell My iPhone's current FAQs explain how battery condition can affect the price offered for a handset.

For more detail, read How iPhone Battery Health Affects Resale Value in the UK.

What about an Unknown camera or front camera?

Camera warnings deserve proper testing because opening the Camera app once does not prove that every camera function works.

Before selling, test:

• the front camera
• every available rear lens
• photo mode
• video recording
• autofocus
• portrait mode, where available
• switching between lenses
• Face ID separately

A phone may take ordinary photographs successfully while another part of its camera system has a fault.

Do not assume Face ID works because the selfie camera works

Face ID relies on Apple's TrueDepth camera system.

Taking a selfie is therefore not a complete Face ID test.

Lock the handset and confirm that Face ID can actually authenticate you.

If Face ID fails, record that as a separate functional issue rather than assuming it is covered by an Unknown Part warning.

What does Finish Repair mean on an iPhone?

Finish Repair means a supported replacement component still needs Apple's calibration process to be completed using Repair Assistant.

It does not automatically mean the component is counterfeit.

Apple's repair process uses calibration data for supported components. Until the process finishes, the phone may continue to show Finish Repair beside that part.

Depending on the component, incomplete calibration can also affect functionality.

If your phone was repaired recently:

check Apple's repair-history guidance

contact the original repairer

ask whether the repair process was completed correctly

avoid immediately paying for the entire component to be replaced again

Important: A repair that needs finishing is not necessarily a repair that needs starting again.

Should you repair an iPhone with Unknown Part before selling it?

Not automatically.

The wrong question is:

“Can I get rid of the warning?”

The better question is:

“Will fixing the problem increase the phone's value by more than the repair costs?”

For example, suppose:

the repair costs £150

the handset is likely to be worth only £80 more afterwards

You have improved the phone technically, but you are £70 worse off financially.

On the other hand, an inexpensive correction to a recent repair may make sense if it restores an important feature or completes the repair properly.

Use the repair-value test

Compare:

What is the iPhone worth now?

What is it realistically worth after repair?

What will the repair actually cost?

Remember to consider more than the headline repair price.

Possible additional costs include:

• labour
• postage
• travel
• time without the phone
• the possibility of further faults
• the risk that the repair adds less value than expected

Our dedicated guide, Should You Repair an iPhone Before Selling It?, explains this decision in more detail.

Practical rule: Repair the handset when doing so genuinely improves the financial outcome, not simply because a warning in Settings looks untidy.

What should you check before selling an iPhone with Unknown Part?

A systematic check takes only a few minutes.

1. Confirm the exact model and storage

Open:

Settings → General → About

Record:

1. iPhone model
2. storage capacity
3. iOS version

Do not guess.

Different storage capacities of the same iPhone can have different resale values.

2. Check Parts and Service History

Look for:

1. Genuine
2. Used
3. Unknown
4. Unverified
5. Finish Repair

Then note which component the message relates to.

3. Test the affected component

Match your checks to the warning.

Display

touch response

brightness

colour

True Tone

flickering

dead areas

Battery

Battery Health

charging

unexpected shutdowns

day-to-day performance

Rear camera

every available lens

autofocus

photographs

video

stabilisation

Front camera

photographs

video

portrait mode

Face ID separately

4. Check the rest of the handset

A buyer will assess the complete phone.

Check:

• front glass
• rear glass
• frame
• charging port
• speakers
• microphones
• cameras
• physical buttons
• Face ID or Touch ID
• battery
• Wi-Fi
• mobile connectivity

An Unknown Part message may be only one factor affecting value.

5. Find any repair paperwork

If you arranged the repair yourself, look for:

• the receipt
• the invoice
• the repair date
• the repairer's details
• the component fitted
• any warranty information

If a recent repair now shows Unknown or Finish Repair, contacting the original repairer may make more sense than paying someone else to investigate immediately.

6. Photograph the phone before sending it

Sell My iPhone's device preparation guide recommends photographing the handset before posting it.

Take clear photographs of:

• the front
• the back
• the left side
• the right side
• the camera area
• any scratches or damage

It is also sensible to save a screenshot of Parts and Service History before erasing the phone.

7. Remove iCloud and your personal data

Before sending the handset:

• back up anything you want to keep
• remove your Apple Account
• turn off Find My
• remove Activation Lock
• erase your personal data
• remove your physical SIM, where applicable

Sell My iPhone has a dedicated guide explaining how to remove iCloud from an iPhone before trade-in.

For more information about erasing a handset, read Factory Reset vs Secure Data Erasure.

Unknown Part, Activation Lock and IMEI blacklist: what is the difference?

These terms describe very different problems.

An iPhone can therefore have:

an Unknown display but no Activation Lock

completely original components but still be Activation Locked

an Unknown component and an IMEI issue

none of these problems

If Activation Lock is the issue you are dealing with, read Can You Sell an iCloud-Locked iPhone in the UK?.

How does Sell My iPhone assess the phone you send?

Accurate condition information is more useful than simply choosing the most optimistic grade.

According to the current Sell My iPhone FAQs:

your initial quote is based on the device and condition you select

the handset is inspected after it arrives

its model and condition are checked

a revised valuation may be issued if the device differs materially from the description supplied

That is another reason to check Parts and Service History before sending the phone.

It is better to understand the handset's condition while it is still in your possession.

How long is a Sell My iPhone quote valid?

Sell My iPhone currently states that quoted prices are guaranteed for 14 days, provided the device received matches the condition described.

After that period, the handset may need to be valued at the current market price.

Once you have:

• checked the model
• assessed the condition
• removed your accounts
• backed up your data
• decided to sell

there is little benefit in leaving the handset unused for weeks.

A practical example: an iPhone 13 with an Unknown display

Imagine you own an iPhone 13.

Its screen cracked last year, so you had the display replaced.

The handset now looks clean and appears to work normally.

However, when you open:

Settings → General → About → Parts and Service History

you see:

Display — Unknown

What should you do?

First, do not assume the iPhone is worthless.

Check:

1. touch response across the entire display
2. manual brightness
3. automatic brightness
4. colour consistency
5. True Tone
6. screen flickering
7. Face ID
8. any other repair-history messages

Scenario one: everything works

Suppose:

touch works perfectly

the screen looks normal

Face ID works

there are no other faults

You now know that you have a functioning iPhone with an Unknown display status.

The warning may affect its valuation or grade, but that is very different from owning an iPhone with a failing screen.

Scenario two: there are functional problems

Now suppose the same phone:

misses touches near the top of the screen

flickers occasionally

has noticeably poor colours

no longer recognises Face ID

The buyer is no longer evaluating only a warning in Settings.

There are genuine functional faults as well.

That distinction explains why there is no sensible universal claim such as:

“An Unknown Part warning reduces every iPhone's value by 20%.”

The effect depends on the actual handset.

Is it worth selling an iPhone with Unknown Part?

In many cases, yes.

A repaired iPhone can still have plenty of usable life and meaningful resale value.

Trying to return every older handset to perfect factory-like condition before selling it can be poor economics.

A better approach is to:

1. identify the repair history
2. test the phone properly
3. check what the handset is worth now
4. calculate the real cost of repair
5. estimate what the phone would be worth afterwards
6. compare the two outcomes

If your iPhone has several faults, start with our broken iPhone pricing guide.

If the handset works and you simply want to see what it could be worth, search for your device with Sell My iPhone.

Ready to value your iPhone?

Once you know the:

• model
• storage capacity
• repair history
• battery condition
• cosmetic condition
• functional condition

you have the information needed to make a sensible comparison.

Check what your iPhone could be worth with Sell My iPhone.

Choose the correct handset and describe its condition accurately.

If the phone has an Unknown Part message or another issue that could affect its grade, take that into account rather than assuming a clean exterior tells the whole story.

Before posting the handset, follow the Six Steps to Prepare Your Device for Sale.

The main steps include:

1. backing up your data
2. removing your accounts
3. turning off Find My
4. erasing your personal information
5. photographing the handset
6. packaging it securely
7. keeping proof of postage

Frequently asked questions

Understanding the Unknown Part message

What does Unknown Part mean on an iPhone?

An Unknown Part message means Apple cannot verify the component in the normal way.

Possible reasons include:

a non-genuine component

a component that is not working as expected

an incomplete verification process after repair

a modified component

Does Unknown Part mean a fake part was fitted?

No.

A non-genuine component is one possible reason, but Apple lists several other causes.

The Unknown message by itself does not prove that a component is counterfeit.

Where can I find Parts and Service History?

On supported iPhones, go to:

Settings → General → About → Parts and Service History

If relevant repair information exists, it should appear there.

Selling an iPhone with repair history

Can I sell an iPhone with an Unknown Part message?

Yes, it can still have resale value.

The final value will depend on:

the model

the component involved

whether that component works

overall condition

battery condition

other faults

the buyer's grading criteria

Does Unknown Part reduce iPhone trade-in value?

It can.

Apple specifically states that an Unknown part might affect trade-in value.

However, there is no universal percentage reduction that applies to every handset.

Should I tell a buyer about an Unknown Part message?

You should describe the phone's condition accurately.

If the handset reports repair history that may affect its grade or functionality, that information can be relevant to the valuation.

Repairs and resale value

Should I repair an Unknown Part iPhone before selling it?

Not automatically.

Compare:

what the iPhone is worth now

what it is likely to be worth after repair

what the repair will cost

Only repair it if the improvement genuinely makes financial sense.

What does Finish Repair mean on an iPhone?

Finish Repair means a supported replacement component has not yet completed Apple's calibration process through Repair Assistant.

It does not automatically mean the component is counterfeit.

Is a Used Apple part bad?

Not necessarily.

On supported devices, Used can identify a genuine Apple component that was previously installed in another iPhone.

That is different from Unknown.

Can an Unknown display affect Face ID?

It depends on the repair and the components involved.

Face ID uses Apple's TrueDepth camera system, so test Face ID separately rather than assuming it works because:

the screen looks normal

the front camera takes photographs

the rest of the phone appears functional

The bottom line

An Unknown Part message on an iPhone is worth investigating before you sell, but it does not automatically mean the phone contains a fake component or has no resale value.

Apple uses the message in several circumstances.

The component may be:

non-genuine

faulty

modified

incorrectly verified after repair

unable to be verified normally

The best approach is practical.

Before selling:

check which component carries the warning

test that component properly

check the rest of the handset

record the repair history before wiping it

compare selling as-is with the cost of repairing it

describe the phone accurately when requesting a valuation

For many people, selling the iPhone honestly in its current condition will make more financial sense than spending heavily simply to remove a message from Settings.

Check the current value of your device with Sell My iPhone →

Sources and further reading

Apple

Apple Support — iPhone Parts and Service History
Apple's guidance explaining Genuine, Used, Unknown, Unverified and Finish Repair statuses.

Apple Support — About genuine iPhone displays
Apple's information on genuine and non-genuine displays, Unknown display messages and potential display issues.

Apple Newsroom — Apple to expand repair options with support for used genuine parts
Apple's announcement explaining its move towards supporting previously used genuine Apple components.

Sell My iPhone

Sell your device — get a valuation

Sell My iPhone FAQs

Six Steps to Prepare Your Device for Sale

How to Remove iCloud From an iPhone Before Trade-In

Sell My iPhone Terms and Conditions

How to Check Your iPhone Model and Storage Correctly Before Selling

How iPhone Battery Health Affects Resale Value in the UK

How to Price a Broken iPhone in the UK: Screen, Battery and Fault Impacts

Should You Repair an iPhone Before Selling It? UK Cost vs Value Guide

Can You Sell an iCloud-Locked iPhone in the UK? Realistic Options

Factory Reset vs Secure Data Erasure: What Matters Before Selling an iPhone