Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
I have p2300 and p2303. I have no ground signal coming from pcm on coils 1 and 2. I have 12 volts on the positive side and I have ground also. I've omhed the signal wires and hot and ground wires and everything ohms out. And I've swapped cam sensors around and it hasn't changed anything the codes still stayed I've also disconnected the battery and tries to drain the pcm then I hooked everything back up and it still has those codes key on engine off before I even start the engine.
What year? Try resetting the keep alive memory or do bypass test at the computer. identify the trigger wire backprobed at the computer, take a voltage measurement, should be 0v if it's not firing, and pull it up with a test light and see if the coil fires.
Also ohming out a wire end to end does not rule out a short to ground so unplug pcm and coil and check wire for a short to ground if you can't make the coil fire.
I've taken a test light to both coils and im not receiving power. Ill do the voltage test at wire coming out of the computer tomorrow. If its not receiving power does that mean more than likely it a computer issue?
I've taken a test light to both coils and im not receiving power. Ill do the voltage test at wire coming out of the computer tomorrow. If its not receiving power does that mean more than likely it a computer issue?
And I've also cleared keep alive memory and the codes are still there as soon as I turn the key on
Just so we're on the same page this is a 2013 with 3 wires going to each coil right?
I will proceed with assuming this is the 3 wire coil.
The code description says short to ground for coil 1 and 2.
Do the codes change if you disconnect coils 1 & 2 and reset KAM? If not then I think you have a short in the harness.
Just perusing the possible codes, it seems the pcm watches that circuit between itself and the coil with some sort of voltage I think. If it sees zero, it will set that code for a short to ground, or circuit low. If it sees anything higher than whatever it's putting out (the PCM), then it will set a code for circuit high or short to voltage.
Last edit: 4 years 3 months ago by jreardon. Reason: wrong coil number
Yes it is a 3 wire coil and a 2013 f150 3.5. I unhooked the pcm and the battery and put one end of my voltage meter on a ground and the other end on the signal wire and it never ohms out I also had it set on 2k ohms and when I plug the pcm back in reads 1.010 ohms if I unplug it, it reads 1 ohms and so does the other signal wires for the coils
For short to ground testing just set the meter to max ohms setting and make sure it reads OL.
I guess you could jump a known good coil signal wire, like from coil #3, and jump that into coil #1 or #2 , reset KAM just for good measure, and see if it sets a code for coil #3.
I don't know if doing a KOEO On Demand Self-test will operate the coils or not but give that a shot too.
I set it the to highest ohms and it read ol then I moved it to 2k and the only time it went from ol to 1.010 was when I plugged the pcm back up and it just did it on coil 1 and 2 but not the others and ill jump coil 3 to coil two and see what it does
So, 1 ohms reading to ground when the computer is reconnected?
Pop the plastic off the connector, the two wires in question are right next to each other.
I'm reading 1.99 ohms and the meter is set on 4 kOhms on the hot side of all the coils with one lead on ground chasis. I think I realized that the signal wire is not my problem lol I'm learning slowly lol
Was this ever resolved? I have same vehicle and same problem. P2300 and P2303. Seems I can unplug the coils on cylinder 1 and 2 and there is no change in how the engine runs. If I unplug any other cylinder then it idles worse. I was getting inconsistent ground and 12 volts from those pigtails so I replaced the pigtails and now I'm getting good voltage to both. Still same issue. Tried swapping coil from a cylinder I know works and no change.
Topic Author
