how can you tell if your ECM is bad in a 2003 honda accord
Usually with some diagnostic equipment.
actually honda has its own built in diag system, if your CEL comes on and stays on its useally a good sign that youhave a bad ECU, however if you see it blink when you cycle the key to ON then you need to read the codes it has. You can do this WITHOUT any diag equipment. Honda has a blue plug up under your pass side kick panel. run a jumper wire on this then turn the key to ON dont try to start the car, just put it in the ON position, it will begin to blink in morse code to you, short blinks and long ones. Google will tell you what is what, "CAR GURUS" is worthless.
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