Canon EOS 6D Mark II Not Turning On: What the Problem Usually Means
If your Canon EOS 6D Mark II is not turning on, the cause is often simpler than a major camera failure.
In many cases, the issue comes down to power delivery, battery contact, a locked switch, or an external accessory blocking startup.
This guide walks through the most common reasons a Canon EOS 6D Mark II will not power up, along with practical checks you can do before sending it in for repair.
Start with the most common power checks
Before assuming internal damage, verify the basics.
The EOS 6D Mark II is a battery-powered DSLR, so any interruption in battery charge, battery seating, or contact cleanliness can prevent startup.
- Confirm the battery is fully charged.
- Make sure you are using a compatible Canon LP-E6N or LP-E6 battery.
- Inspect the battery for swelling, cracked casing, or leaking.
- Reinsert the battery firmly until the latch clicks.
- Check whether the battery door is fully closed, since some cameras will not power on if the door sensor is not engaged.
If you use a third-party battery, try an original Canon battery as a test.
Some replacement batteries can appear charged but fail under load.
Check the power switch and shooting mode
The Canon EOS 6D Mark II has a three-position power switch.
It should be set to ON, not the middle position that may disable normal operation depending on how the controls are being used.
Also confirm the camera is not simply appearing dead because the display is off or dimmed.
Turn the switch fully on, then press the shutter button halfway to see whether autofocus or exposure indicators activate.
Look for signs of partial power
If the camera shows any LED activity, viewfinder display, or autofocus response, the issue is likely not a complete power failure.
That points toward a display setting, lens communication issue, or a control lock rather than the main power circuit.
Remove accessories that can interfere with startup
Accessories can stop a DSLR from starting properly, especially if they are faulty or drawing too much power.
Strip the camera down to a basic configuration and test again.
- Remove the lens.
- Take out the memory card.
- Detach the flash, battery grip, remote trigger, and cable accessories.
- Disconnect any USB or HDMI cables.
After removing everything, reinstall only the battery and try turning the camera on.
If it powers on in this bare setup, one of the removed accessories is likely the cause.
Test the memory card and card slot
A damaged SD card or a problem in the card slot can occasionally create startup issues.
Although the camera should usually still power on without a card, card-related faults can sometimes cause erratic behavior.
Test with no card installed.
If the camera powers up, insert a known-good SD card from a trusted source.
If problems begin after inserting a specific card, reformat it in-camera only after saving the files elsewhere.
Also inspect the slot for bent pins, debris, or a broken card latch.
Never force a card into the slot.
Reset the camera’s basic settings
If the camera has partial power but behaves oddly, a settings reset may help.
On the EOS 6D Mark II, use the menu system to restore camera settings and clear custom behavior that may be confusing the startup process.
However, if the camera is completely dead and no screen appears at all, a menu reset will not be possible.
In that case, focus on the battery, contacts, and hardware checks first.
Inspect battery and camera contacts
Dirty or oxidized contacts can interrupt current flow.
Look closely at the metal contacts on both the battery and inside the battery compartment.
- Use a clean, dry microfiber cloth for light cleaning.
- For stubborn residue, use a cotton swab with a small amount of isopropyl alcohol and let everything dry fully before reinserting the battery.
- Do not use water, abrasive tools, or excessive force.
If the battery contacts appear pitted, bent, or discolored, the camera may need professional service.
Try a second battery and charger
A battery can show a charge indicator on the charger and still fail to provide enough voltage to boot the camera.
This is common with older LP-E6-series batteries.
Use a second known-working battery and, if possible, a different charger.
If the second battery powers the camera on, the original battery is the problem.
If neither battery works, the fault may be in the camera body or its contact assembly.
Rule out lens or mirror-box issues
Some startup problems are actually caused by lens communication errors or a stuck mechanical component inside the body.
Testing without a lens helps separate body faults from lens faults.
If the camera powers on body-only but shuts down with a specific lens attached, inspect the lens mount contacts and try another Canon EF lens.
A damaged aperture connection or shorted lens can cause the body to fail its startup check.
Listen for unusual mechanical sounds such as clicking, grinding, or repeated motor attempts.
Those can point to a mirror, shutter, or internal drive issue that requires repair.
Watch for overheating or environmental damage
Extreme temperatures, moisture, and condensation can stop a Canon DSLR from starting.
If the camera was recently used in rain, near salt water, or moved from a cold environment to a warm one, allow it to acclimate in a dry place.
Remove the battery and memory card, leave compartment doors open, and let the camera sit in a dry environment for several hours.
Do not apply heat directly.
If moisture intrusion occurred, professional inspection is safer than repeated power attempts.
When the camera still will not turn on
If the Canon EOS 6D Mark II is not turning on after you have tried a charged genuine battery, removed accessories, cleaned contacts, and tested the camera body alone, the issue is more likely hardware-related.
Possible internal causes include:
- Faulty power switch assembly
- Damaged battery terminal board
- Broken door sensor
- Failed main circuit board
- Short circuit from moisture or impact damage
At that point, continued attempts to power the camera may not help and could worsen the fault if there is internal corrosion or an electrical short.
When to contact Canon service or a repair shop
Seek professional repair if the camera has visible damage, liquid exposure, a swollen battery compartment, or no response from multiple known-good batteries.
A technician can measure voltage paths, inspect the power board, and test components that are not user-serviceable.
If the camera is under warranty or covered by a service plan, contact Canon support first and document everything you already tested.
That can speed up diagnosis and reduce duplicate troubleshooting.
Quick troubleshooting checklist
- Charge and reseat a genuine LP-E6N or LP-E6 battery.
- Test with a second known-good battery.
- Verify the power switch is set to ON.
- Remove lens, memory card, and all accessories.
- Clean battery and compartment contacts.
- Check the battery door latch and sensor.
- Look for moisture, impact damage, or unusual noises.
- Test the camera body with no lens and no card.
Working through these checks usually reveals whether the Canon EOS 6D Mark II not turning on problem is caused by a battery, accessory, or body-level fault.