#Mack truck starter relay location driver#

If the relay shorts it can leave power on to the computer, even when the vehicle is turned off. Battery drain or dead batteryДЄ failed ECM power relay can also cause a battery drain or dead battery. A bad relay may cause the vehicle to crank, but not start, or sometimes not even crank at all.

If the ECM or itвЂ™s relay fail, the entire engine management system will be left without power and will not function as a result. The fuel and ignition systems, as well as several other engine management functions, of many vehicles are controlled by the ECM. Engine will not startДЄnother common symptom of a problem with the ECM power relay is an engine that will not start or turn over. A failed relay will disable the dash lights and warning chimes that normally come on when the key is inserted into the ignition, and will probably be unable to start or turn over the vehicle. If the ECM power relay fails it can cut off power to the entire vehicle. One of the first symptoms of a problem with the ECM power relay is no power when the key is inserted.

#Mack truck starter relay location driver#

Usually a problem with the ECM power relay will produce a few symptoms that can alert the driver of a problem that should be serviced. If the relay fails, or has any issues, it can cause the vehicle to have all sorts of problems, and may even render it undriveable. The ECM power relay is the relay responsible for sending power to the ECM. It is a very important, if not the most important component of a modern engine management system, and just the same as any other important electrical component it is powered through a relay. It is the central control unit of most vehicles and controls a variety of functions, such as electrical system power distribution, emissions, ignition, and fuel systems. The ECM, or electronic control module, is the computer responsible for controlling all of the engine management functions.