It took a while to learn my car suddenly wouldn't start because of the ECU. When I opened it up there was a burnt component on the main board. There are many of these components on main board. I don't know what they are . .they don't look like resistors, capacitors or diodes that I have seen in other electronic systems. I have ordered 2 used ECU units with the same part number, but wonder if the ECU was fried because of a short elsewhere in the car's system. For a component to "burn" it has to be overloaded by something !. Any ideas.

 

Any photos?

 

I can't get photos right now . . the car is stuck somewhere else because it doesn't run. I will get back to it next week when I get the replacement ECUs. I guess a question is, does the controller switch high current devices? or does it just signal to smart devices that control the high current devices ? I just don't want to POP another controller because of a problem somewhere else in the car.

 

The ECU is powered through the 30A EGI fuse (located in fuse block next to battery) and the main relay. Not sure what the total current draw is, but is obviously limited to 30 amps. The ECU essentially drives the air flow meter, metering oil pump position sensors, throttle position sensors, ignition coils/igniters, fuel injectors, crank angle sensor, and numerous other emissions related sensors, solenoids and switches. I'm not sure which of these draws the most current. Probably the injectors draw the most current at about 1-2 amps each. It may be that one of your electrolytic capacitor blew and created a short circuit within the ECU. It's anyone's guess what caused the ECU to short out.