Fujinon XF 18-55mm: 'Turn off and turn on camera again' Error - Diagnosis

⚠️ SAFETY WARNING / ESD RISK. This procedure involves precision optical-electronic components. Before performing any operation, turn off the camera and remove the battery from the camera body. During lens disassembly, work in a dust-free environment and protect circuits from electrostatic discharge (ESD). ReeFix provides this diagnosis EXCLUSIVELY for educational and informational purposes.

CHECK 1

Bayonet contact cleanliness and stability (Probability: ~15%)

This often happens when the error appears intermittently by slightly moving the lens on the camera.

1. Turn off the camera and remove the Fujinon XF 18-55mm f/2.8-4 R LM OIS lens.
2. Inspect the 10 golden pins on the rear bayonet: ensure there are no traces of grease, oxide, or pins stuck in their spring seat.
3. Moisten an ESD microfiber cloth with 99.9% isopropyl alcohol for electronics cleaning and thoroughly clean the contacts of the lens and the camera body's Fuji X-Mount.
4. Perform an isolation test by mounting the lens on a second Fujifilm camera body. If the error disappears, the cause was an unstable electrical contact. If the anomaly persists, the problem is internal to the lens.

CHECK 2

Dynamic zoom inspection and flex cable wear (Probability: 65%)

The dominant cause for this specific model is mechanical fatigue fracture of the aperture flex ribbon cable, caused by continuous zooming between 18mm and 55mm.

1. Turn on the camera with the lens set to the minimum focal length (18mm). Take a few photos while varying the aperture.
2. Slowly rotate the zoom ring towards 55mm and take a new shot.
3. Key indicator: If the "Turn off and turn on camera again" error occurs only when extending the barrel towards longer focal lengths (or disappears returning to 18mm), the internal flex copper micro-traces are broken.
4. Repair notes: The intervention requires disassembling the rear bayonet using a JIS precision screwdriver set for camera on eBay, disconnecting FPC connectors with ESD tweezers and an antistatic repair spudger, and replacing the aperture flex cable specific to the lens.

CHECK 3

Autodiagnosis of Linear Motors (LM) and OIS Unit (Probability: 12-20%)

At startup, the camera's MCU system sends a serial pulse to verify the alignment of the autofocus magnetic linear motors and optical stabilization (OIS).

1. Place your ear close to the lens upon powering on.
2. Warning sign: The presence of a metallic hiss, an abnormal vibration, or a sharp "click" followed by the error indicates that the Hall effect sensor is not detecting the correct centering of the floating coils (mechanical stall or internal debris).
3. In the lab, diagnosing the magnetic winding and lens control board requires an SMD inspection using a Stereo microscope for board repair on eBay and using a Precision hot air soldering station on eBay.

CONCLUSION

• Most probable case (65% - Broken aperture flex cable): If diagnosis confirms lockup during zoom movement, DIY repair requires excellent dexterity and the replacement part (~€12-25). In a repair shop, the cost usually ranges between €90 and €130.

This flex circuit wear phenomenon during zoom travel is similar to what happens on zoom lenses from other brands, as explained in the repair guide for Canon 24-105mm f/4L IS USM: Err 01 Error and Solution.

• Secondary case (15% - Oxidized/dirty contacts): Solvable independently at zero cost by cleaning the pogo pins with isopropyl alcohol.
• Complex case (12-20% - LM motor / OIS module / PCB failure): If the error is immediate at all focal lengths and accompanied by noises/vibrations, technical intervention requires replacing the internal optical block (€150-200). If the cost exceeds €220, buying a used replacement is the most cost-effective choice.

Handoff for the repair shop: "Fujinon XF 18-55mm exhibits firmware lockup at startup. Check electrical continuity of aperture flex cable during zoom travel, LM motor winding impedance, and resistance on bayonet contacts."

If the error appears when turning the zoom towards 55mm -> replace the aperture flex cable; if the error is persistent at 18mm even after cleaning contacts -> send for service for linear motor module diagnosis.