Steve D

I was driving my 1995 F150 with a 5.0L engine. I pulled into a driveway and began to back out when the engine stopped. Now it will not start. There is no output from the coil. I have made the book tests and didn't find any wire damage. Now I don't understand what is keeping me from getting input voltage to the ICM. It looks like the power comes from the IGN SWT but I don't know how to check the ignition switch. However, the wiring diagram looks like power goes through the Powertrain Control Module. I could use some guidance.
This is my first post, so I hope I am doing this correctly.

memoniz

The standard first answer is check your codes. My next thing to check is the ICM. The ICM sends a signal to the coil for it to spark. There are test for it in the book, but most chain parts stores can test it. If you did the test to check the coil, and if the ignition system is TFI-IV, then it could be the PIP sensor in the distributor. There is a test for that in the book also. After that I would look at the ignition switch and then the PCM. I hope that helps, but usually the ICM is the weak link.

Steve D

Thank you for the help. I am getting a solid light at the Tack pin on the coil. the ohm's are good between the ICM and coil, however, I have no voltage at the ICM. the wires are all looking good with no breaks of chaffing. It seems to be down to the ignition switch and PCM. I don't know how to test the PCM. From what I understand the PIP will not function if the ICM is not getting power.

memoniz

To be honest with you, I would still be looking at the ICM. It is kind of strange for the truck to just stop working if you got it started and backed up some then have it fail. Not to say that the other possibilities can't happen, in my experiences, I've seen more ICM failures than any other problem. If you have an Autozone in your area, you can by one with a lifetime warranty and they will generally take back any part that you buy. I would get an ICM, switch it out and see if that works. If it doesn't, put the old one in and return the new and all you would loose is some time and gas. I have had PIP sensor problems twice. One time a mechanic replaced with a used distributor and once I replaced with a new. Very random when they fail, which makes it hard to pin the problem down. It will work fine one minute, fail the next, and work again later. I've read about people having ignition switch problems, even changed mine once, but usually there are other signs of things going wrong when that happens. Same with the PCM. I changed mine thinking that was my starting problem, but it was the PIP sensor.

You never said if you've pulled codes. Have you done that? Usually that will point you in the right direction if you understand what they mean.