With a diagnostic computer.
check the crankshaft and/or camshaft position sensors, if they are not working the ECU will not "see" the engine turning, therefore no need to spark..
Some signs that your engine control unit is not working properly are car failure, bad gas mileage, and your car running poorly. If your check engine light is on, that might also indicate an ECU problem.
Maybe you have to check the A/C Ecu located in the engine bay.
check your answer
Connect an OBD2 scan tool which will retrieve the codes set by the ECU. If you mean how to check to see if the light is working just turn the key on without starting the engine. The check engine light will illuminate.
The VSS (Vehicle Speed Sensor) is located on the transmission. If the speedometer is not working, it is rarely the VSS causing the problem. I would first check fuses and the ECU
A car will not operate without the a working ECU. If the computer is bad car will not turn on. A driver will not be able to use any of the engines accessories.
Check under the radio.
Engine check urgently
its the engine control unit... it manages all the working of the motor
check your fuel pressure regulator. it is on the fuel rail on top of engine or in the gas tank depending on your car.
Not likely. If the computer was malfunctioning, you're performance would be junk or the car wouldn't even start. If you need confirmation, a mechanic with computer diagnostics can tell if your ECU is working or not.