How to Replace a Bad Sensor in Your Car or Truck

If your warning light is on when your engine is running, but there is nothing wrong with the part it is indicating to be broken, you probably have a bad sensor. A bad sensor is something you should fix if you can, especially if it monitors something such as oil pressure or another thing that is designed to stop the engine before there is a major problem.

Every vehicle is different, and every sensor is different, therefore you should always have a repair manual for your specific vehicle that can help you locate and change your sensor without difficulty. There are some basics places sensors usually are. For instance if you have a problem with your anti lock brake sensor you will probably find it connected to the backing plate of one of your rear wheels. Or if you have an oil pressure sensor that is not working you will find it by the engine. Normally the sensor screws into what it senses, meaning all you need to remove it is a big wrench, but on more modern vehicles you might find that two or three screws hold the sensor in place.

If the sensor you want to replace screws in take a piece of tape, If you can make it colored so that you will easily be Able to find it, masking tape will also work, but black electric is sometimes hard to find, and put it on the wire you take off of the sensor. This will allow you to know where it goes when you are putting it back together. If there is more then one wire, you might want to use masking tape, and a pen to put a number on the wire, that matches where it goes. Now carefully unscrew the sensor, and make sure that there isn't any dirt falling in the hole, and replace it with the new one. Be very careful that you put it in the correct way because it could be disastrous if you accidentally cross thread the bolt. Especially if the sensor is for oil or otherwise connected to the engine. Now that you have the sensor back in place, reconnect the wires.

If the sensor you want to replace has screws holding it on, take the screws out and remove the whole sensor first. Now that the sensor is loose, take the wires off of your old sensor and put them correspondingly on your new sensor. And carefully screw it back into place with the old screws. This is also a time that you have to be very careful that you do not cross thread the screws.