Scanners aren't 100% accurate reading FICM
voltage. I've used AE
before which read 47.5V across the board, but when I put a voltmeter on it and tested it the right way, cranking voltage dropped below 20. Check it with a voltmeter.
On top of the FICM
is a little access plate. Two small torx screws (which are super easy to drop and lose forever, lol). Take off the plate, underneath there will either be 4 pins or 7. By pins I mean small screw heads. You said 03 model, so you could have 7. I'm not sure which pin you test in the 7pin models...look that part up if you have 7. But if it's a 4 pin, which most are now, you'll test the far right pin, closest to drivers side fender. Wrap electrical tape around the hot (red) probe in your volt meter, only leaving the tip exposed. This will keep you from shorting it out on the case like mentioned above. Ground probe goes to negative battery post. Check voltage key on engine off (KOEO
), then again while cranking, then while running. At no point should it drop below 46v.
My guess is that your low voltage issue killed your FICM
. They have a tendency to clear up when warm just like injector stiction does. Low voltage kills them almost every time. Keep,driving on a bad FICM
and you'll kill injectors.