How to Troubleshoot Why Wiper Blades Won't Work

Since there is no single wiper blade that fits every car, there is no one exact method of troubleshooting when a wiper blade system is failing. There are, however, some general steps to try to help diagnose the reason why your wiper blades will not work. Some of the possible problems can originate under the hood of the vehicle, with the electrical components, or with the wiper arm or blade itself.

Things You'll Need

  • Socket wrench
  • Check your fuses if the wipers do not move at all. Consult your vehicle owner's manual for the location of the fuse box as well as a diagram indicating the location of the fuse that corresponds with the wipers. If you have a bad fuse, replace it and see if the wipers work again. If they still do not move, it could be a wiring or relay issue, which should be diagnosed by a professional mechanic.

  • Turn the car on and listen the wiper's motor. If you hear any noise coming from the motor or the wipers move erratically, it will likely have to be replaced or fixed. Other than noise coming from bad wipers rubbing against the windshield, most other noises can be attributed to the wiper motor or other components under the hood.

  • Check both wiper arms. This is the part that connects your wiper blade to the motor. If they are bent in any way, replace them. Replacement involves removing the cover at the base and removing them with a socket wrench.

  • Examine how the wiper blades are mounted on the wiper arm. Depending on type of connection, the blades may not be mounted properly. Lift the blade off the windshield and check to see if the mounting connection is loose. Examine the safety mechanism at the center of the wiper. This mechanism usually features either a button or a tab, and differs by brand and connection type. If the connection is loose, see if you can push it back into place. If you hear a click sound, then the mechanism is engaged and has secured the wiper to the arm. If you don't hear a click sound, the safety/release mechanism is likely broken; if so, replace the wiper blade.

  • Examine the wiper blade unit, which is attached to the arm, but is not part of the arm itself. If it is bent in any way, remove and replace the entire wiper blade. Bent wiper blade units will distort the actual rubber or silicone blade used to remove rain or snow from your windshield.

  • Check the rubber insert in the wiper blade. If it's worn down, it should be removed and replaced. In same cases, it is easier to just replace the whole blade unit.