- Printers
- Laser printer
size-error-2-sided
Brother MFC-L8900CDW: Size Error 2-sided
Risk level
Medium
Proceed carefully and stop if the check is unclear.
Urgency
High
Quick answer
Brother defines “Size Error 2-sided” as: The configured or loaded paper size is not supported for automatic two-sided printing. That message alone does not prove a replacement part. The next useful discriminator is requested size, tray setting, actual dimensions and whether the same job succeeds in simplex.
Safety first
Stop and check this first
- Use only media and sizes supported by the selected tray and duplex path.
Safe checks you can perform
- Preserve the exact display and context
- Run one controlled owner-safe discriminator
- Stop at the proved owner/service boundary
Leave these tasks to a qualified professional
- Do not attempt this professional task: Measured handoff for Size Error 2-sided
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.
Measured handoff for Size Error 2-sided
What they doCompare job ticket, tray settings and measured sheet, then test the relevant size/type sensors and registration timing before replacing hardware.
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.
Preserve the exact display and context
Photograph “Size Error 2-sided”, including any tray, color or ## suffix. Save model/region, page count, supplies-life page, job/media and the last intervention before clearing it.
Use only media and sizes supported by the selected tray and duplex path.
Evidence: Brother MFC-L8900CDW Online User's Guide - error and maintenance messages
Run one controlled owner-safe discriminator
Record the job-requested size/type, tray-configured size/type and actual sheet dimensions/media. Correct only the mismatched layer and retest one sheet. Record requested size, tray setting, actual dimensions and whether the same job succeeds in simplex; change only one variable before retesting.
Use only media and sizes supported by the selected tray and duplex path.
Evidence: Brother MFC-L8900CDW Online User's Guide - error and maintenance messages
Stop at the proved owner/service boundary
A mismatch between those three values is configuration/media, not hardware. If all agree and the message repeats, service the size/type sensing and registration branch.
Use only media and sizes supported by the selected tray and duplex path.
Evidence: Brother MFC-L8900CDW Online User's Guide - error and maintenance messages
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
- Printers
- Brand
- Brother
- Product type
- Laser printer
Known code variants
- Brother Erreur format recto verso
- Brother Error de tamaño a doble cara
- Brother Errore formato fronte-retro
- Brother Formatfehler Duplex
- Brother Size Error 2-sided
- Erreur format recto verso
- Error de tamaño a doble cara
- Errore formato fronte-retro
- Formatfehler Duplex
- MFC-L8900CDW Erreur format recto verso
- MFC-L8900CDW Error de tamaño a doble cara
- MFC-L8900CDW Errore formato fronte-retro
- MFC-L8900CDW Formatfehler Duplex
- MFC-L8900CDW Size Error 2-sided
- Size Error 2-sided
What it means
Official meaning: The configured or loaded paper size is not supported for automatic two-sided printing. Decision boundary: record requested size, tray setting, actual dimensions and whether the same job succeeds in simplex. Service or purchase proof: Compare job ticket, tray settings and measured sheet, then test the relevant size/type sensors and registration timing before replacing hardware.
Warnings and stop conditions
- Mediumsource verified
Use only media and sizes supported by the selected tray and duplex path.
Evidence: Brother MFC-L8900CDW Online User's Guide - error and maintenance messages
Symptoms and causes
Probable causes · in order
- What the Brother message establishesConfirmed
The official Brother MFC-L8900CDW family guide defines “Size Error 2-sided”: The configured or loaded paper size is not supported for automatic two-sided printing.
Evidence: Brother MFC-L8900CDW Online User's Guide - error and maintenance messages
- The observation that changes the next branchPossible
Capture requested size, tray setting, actual dimensions and whether the same job succeeds in simplex. A mismatch between those three values is configuration/media, not hardware. If all agree and the message repeats, service the size/type sensing and registration branch.
Evidence: Brother MFC-L8900CDW Online User's Guide - error and maintenance messages
Virtual technician
Does size-error-2-sided 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
Brother MFC-L8900CDW Online User's Guide - error and maintenance messages
Brother Industries, Ltd. · 2021 · official_doc
Was this entry useful?