My camera all of the sudden stopped working. What is going on?

Question

My camera all of the sudden stopped working. What is going on?

Answer 1

if by camera you are referring to iSight, here is how to troubleshoot:
Built-in iSight cameras
These steps are for iSight cameras that are built into a computer, such as the iMac G5 (iSight) or later, the MacBook, or MacBook Pro.
See if the issue is application-specific.
Try another application (iSight works with applications like iChat, PhotoBooth, and iMovie HD 6) to see if the iSight camera exhibits the same behavior in all applications. If it only happens in one application, try reinstalling that application.
See if the issue is user-specific.
Test your iSight camera in another user account. If the issue only occurs in one user, the issue would be isolated to user settings.
Find out if the computer recognizes the iSight
Check System Profiler (in the Utilities folder, inside the Applications folder). Under the USB header, check to see if the iSight camera is detected.
Reset SMC or PMU
Reset your computer's SMC or PMU, and then check System Profiler again. (SMC reset instructions for iMac G5 (iSight), Intel-based iMacs; PMU reset instructions for MacBook and MacBook Pro.)
If your built-in iSight camera is still not behaving correctly after trying all these steps, you may need to contact Apple or an Apple-Authorized Service Provider for service.
Standalone iSight cameras
The instructions in this section apply if you have an iSight camera that is not built into your computer but attaches to the computer via a FireWire cable.
Make sure the cable is completely plugged in.
Incomplete cable connections are the most common cause of hardware problems. Follow these quick instructions to make sure your iSight cable is completely plugged in.If your iSight camera continues to function improperly, continue on to the steps below.
Turn the computer and the camera off.
Unplug the FireWire cable from your computer and the camera.
Wait a few seconds.
Firmly, without forcing, plug the cable back in to the camera and the computer.
Caution: FireWire ports are keyed so the FireWire cable can only be inserted one way. Make sure you are inserting the FireWire cable into the FireWire port in the correct orientation.
Restart your computer.
If the green light on top of the iSight is not lit, turn on the camera by gently twisting the lens.
Launch iChat AV.
See if a different FireWire port works.
Some Macs have more than one FireWire port. If your computer has another FireWire port, disconnect the iSight camera from the current port and plug it into the other one. Restart your computer and test the camera before continuing to step three.
Check to see if other FireWire devices work.
If you have another FireWire device, such as a video camera or an external hard drive, try plugging it into your computer to see if it works. If your other FireWire devices work, this means that your computer's FireWire port is working correctly. If your other FireWire devices don't work, there may be an issue with your computer. Contact an Apple Authorized Service Provider for assistance.
Determine if there is an incompatibility with another FireWire device.
If more than one FireWire device is connected to your computer, there may be an incompatibility between two of the devices. To rule this out, disconnect all other FireWire devices from the computer, including external hard drives, CD/DVD drives, other cameras, and FireWire-based networking equipment, such as hubs and repeaters. If your iSight camera works normally when you remove other FireWire devices, plug them back in one at a time to isolate the cause of the issue.
Make sure the FireWire cable is good.
Follow these steps to test the FireWire cable:Information about your iSight camera should appear in the FireWire Information field. If you see the iSight camera in this field, your cable is good. Once you've confirmed the cable you are using is good, use it to plug your iSight into your computer. If the green light on the top of the camera does not light up immediately (within a second), there may be an issue with your camera. Fill out an iSight Service Request to have your camera repaired.
Important: Do not send your iSight camera for repair until you have tried each troubleshooting step.If the FireWire cable that came with your iSight camera didn't work, try another FireWire cable that you know works. If this cable works, there is an issue with your iSight's FireWire cable. If your camera is in the limited warranty period, fill out an iSight Service Request to receive a replacement cable.
Choose About This Mac from the Apple menu.
Click More Info. System Profiler opens.
In the System Profiler window, click on the Devices and Volumes option.
Click the disclosure triangle, if necessary, in the FireWire Information area.
Check to see if there is an issue with your camera.
If information about your iSight appears in System Profiler but the camera still does not work, follow these steps:Video from your iSight camera should appear on screen. If the screen is blue or black, there may be an issue with the camera. Fill out an iSight Service Request to have your camera repaired.
Open iChat AV.
Choose Preferences from the iChat menu.
Click the Video button.
Twist the front of the iSight camera lens to open the iris barrier. The green light on the camera turns on when the iris barrier is open.