Canon’s Error 99: the Man, the Myth
Posted by Roger Cicala
Common Causes of Err99
I’m listing these in my own perceived order of frequency, combining our experience at LensRentals with reading countless online Err99 reports. The list has been revised after further information from Precision Camera about actual causes they see during repair. One important thing they reminded me of: when we see Err99 on the screen, the camera actually has more information about the cause of the error internally. A repair shop can read this information from the camera and often determine the cause with complete accuracy.
- Lens/camera electrical contact failure
- Lens circuit (AF or IS) failure
- Camera electronic circuit failure (see below)
- Battery or Grip problems
- Broken or stuck lens aperture diaphragm – Note: this most often happens only when the lens is completely stopped down. If you have questions about the lens, shoot it both wide open and stopped down. If Err99 appears when stopped down, its an aperture issue.
- Older third-party lens with incompatible electronics
- Jammed or damaged camera shutter curtain
- Mis-formatted or damaged card
- Damaged or corroded cell within camera battery
- Failure of the sequence motor—according to precision this is unusual, but does occur, especially in older cameras that have been through a shutter replacement.
- Corroded battery or camera contacts
- Incorrectly mounted battery grip, particularly if it’s too loose
- Camera/hot shoe electrical contact failure
- Moisture condensation within camera or lens (or corrosion occurring days or weeks after moisture exposure)
Most of us cannot define in-camera circuitry failure more specifically than “it went to Canon for repair”, but a few skillful individuals have disassembled their Err99 frozen cameras and reported things like loosened solder splats that were causing shorts, ribbon cables not firmly seated in their connectors, loose metal shields in the camera that could move enough to short or ground an electrical part, etc. If you’ve never seen the insides of a digital SLR, there are an amazing amount of electronic connections packed into basically no space in there.
103 Responses to “Canon’s Error 99: the Man, the Myth”
amy said:
I have a cannon rebel with a 300 mm lens, the lens reads error 99 in cold weather and or to bright a light’ I have taken to smacking the lens for the last 2 years and it works as long as I shut of the camera first..I use the small lens that came with the camra with no problems..my camera is now 4 years old but it still works great..the lens is the pproblem
Melvin said:
Had this issue 2-3yrs now on my 30D. Had to take out battery and rub battery contacts in a fast motion on my clothing to build up static, reinsert into camera just to get another 6 shots and then repeat it again.
SOLUTION: Drain camera battery dead as possible and put in fridge overnight. Take 2 car batteries and connect (+) posts together and do same with the (-) posts. Now run a loose wire off (-) post and another off the (+) post. Take the (-) wire from car battery and hold it or tape it on the (-) of your camera battery. Take wire coming off (+) post of car battery and rapidly tap it 7 times on the (+) leg off camera battery. Wait 30 seconds and repeat. WEAR GOGGLES!
Now insert camera battery into camera and kiss error99 goodbye! Good for another 2,000 cycles b4 error99 reappears.
Better yet…buy a new battery! Best…sell your Canon gear and buy a Nikon Camera because who needs this crap?