When your Canon printer not working properly, then you need to perform Canon printer troubleshooting. Using the troubleshooting techniques, you can identify the root cause of the problem. There are multiple reasons why your Canon printer must have stopped working abruptly. You will have to troubleshoot for the following reasons: 1. The main power line must have become loose. You need to tighten it up so that the printer gets the power. 2. The USB cable between the printer and the PC must have become loose. Remove and insert the cable between the two devices. 3. The ink in the cartridges must have got depleted. Replace the cartridges with the new cartridges.