Some checks for an electric motor that is acting up are quite simple, more so than checking for engine trouble under your car's hood. This is because problems with an electric motor may be caused by wiring and other simple parts that are easy to pinpoint and replace, rather than all the complicated systems and parts that can cause a car engine to fail. If you have an electric motor that is acting up, begin with these simple checks and note if you can address the problem yourself. 

1. Fuses

Check the fuses of the motor to see if any are blown, but remember that blown fuses can sometimes be a symptom of a larger problem, not the problem itself. If fuses continuously blow, it's time to check the wiring of the motor and the demands you're putting on it, as trying to run too much power through an electric motor can mean continuously blown fuses. In turn, you may change the fuse to get the motor running again but it will typically just burn out again eventually. Note how often you need to replace fuses when an electric motor acts up and then check the wiring to see if that's the actual cause of the problem. 

2. Line to line checks

Check the voltage of all the line connectors and you may be able to pinpoint the problem with your electric motor. If one is not getting voltage, chances are it's a connector between lines or a line that is bare and frayed and needs replacing. A voltage meter is relatively inexpensive for purchase so you can check the motor yourself, or a repair shop may perform this check for free or at a very low cost, and it can tell you what lines need replacing for your motor to run again.

3. Junction box

Inside the junction box, you need to check for lines that are not insulated properly and for insufficient grounding. These are common cause of an electric motor to fail. Loose connections can mean improper grounding, and if the junction box is not insulated properly, this can mean moisture buildup that causes shorts inside the box. Test the lines inside the junction box for proper voltage so you know which connections to examine and if there have been shorts or if the wires are bare and need replacing.

4. Bearings

Bearings are located at the ends of an electric motor, inside what are typically called bell housing. They allow the shaft to move freely and when bearings begin to fail, you usually hear a loud whine or squealing sound. Most bearings are meant to be maintenance free so if you notice this sound, the bearings usually just need changing rather than lubrication or other maintenance.