04 Vic sudden loss of start, OBD II comms, and other weirdness
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04 Vic sudden loss of start, OBD II comms, and other weirdness
Hello. I have an 2004 Ford Crown Victoria 8 Cylinders W 4.6L FI SOHC 281 CID with VIN 2FAFP74W54X177766
About 4-5 days ago I started normally, rolled down the driveway and waited for traffic to pass before trying to turn onto the road. When it was clear the moment I hit the gas it died. No gradual loss of power, no noises, no nothing, just sudden death. At that time I tried to start again and it cranked but it would not run. Normal crank and everything but it would not run. I happened to have an ODB II scan tool in the seat next to me since I had just had it smogged and it passed. When I plugged it in it turned on but it would not link. I made sure it was connected fully and that the ignition was in run but it still would not link. I had some things to get to so I pushed it back into place and called a friend for a ride and decided to deal with it the next day.
First thing in the morning I went and tried to crank it again and it wouldn't crank at all. Connected OBD II scan tool but still no link. I also suddenly noticed that while I had the ignition in run the IAC valve was chattering and the fuel pump kept running. I unplugged the IAC and that's when I heard the fuel pump continuously running. I went ahead and did a visual inspection of all fuses and the only fuse I found blown was the fuse for the upper cigarette lighter, I don't think it's related as replacing it didn't solve anything. I then went and investigated all the relays I could find and confirmed they worked properly. I also checked the starter by shorting the relay pins in the fuse box with a pair of needle nose pliers and it cranked just fine, just won't run. I left the IAC unplugged and the fuel pump relay unplugged so that I could investigate further without draining the battery out. I checked voltage on the battery and it's fine as well (also implied by normal bypassed crank.) I've performed a visual inspection of all wire harnesses and connectors I have access to and used a bore scope on the inner wiring harnesses behind the steering wheel and instrument cluster and didn't find anything obvious there either. The only thing left is to check the PCM connections.
I also accidentally found that my horn doesn't work from the steering column. The keyless entry system horn activation works fine and I can also activate the horn by bypassing the relay so I know the horn itself works, just not user operable normally on the steering wheel.
Does anybody have a PCM connector pinout/diagram for my Crown Vic?
About 4-5 days ago I started normally, rolled down the driveway and waited for traffic to pass before trying to turn onto the road. When it was clear the moment I hit the gas it died. No gradual loss of power, no noises, no nothing, just sudden death. At that time I tried to start again and it cranked but it would not run. Normal crank and everything but it would not run. I happened to have an ODB II scan tool in the seat next to me since I had just had it smogged and it passed. When I plugged it in it turned on but it would not link. I made sure it was connected fully and that the ignition was in run but it still would not link. I had some things to get to so I pushed it back into place and called a friend for a ride and decided to deal with it the next day.
First thing in the morning I went and tried to crank it again and it wouldn't crank at all. Connected OBD II scan tool but still no link. I also suddenly noticed that while I had the ignition in run the IAC valve was chattering and the fuel pump kept running. I unplugged the IAC and that's when I heard the fuel pump continuously running. I went ahead and did a visual inspection of all fuses and the only fuse I found blown was the fuse for the upper cigarette lighter, I don't think it's related as replacing it didn't solve anything. I then went and investigated all the relays I could find and confirmed they worked properly. I also checked the starter by shorting the relay pins in the fuse box with a pair of needle nose pliers and it cranked just fine, just won't run. I left the IAC unplugged and the fuel pump relay unplugged so that I could investigate further without draining the battery out. I checked voltage on the battery and it's fine as well (also implied by normal bypassed crank.) I've performed a visual inspection of all wire harnesses and connectors I have access to and used a bore scope on the inner wiring harnesses behind the steering wheel and instrument cluster and didn't find anything obvious there either. The only thing left is to check the PCM connections.
I also accidentally found that my horn doesn't work from the steering column. The keyless entry system horn activation works fine and I can also activate the horn by bypassing the relay so I know the horn itself works, just not user operable normally on the steering wheel.
Does anybody have a PCM connector pinout/diagram for my Crown Vic?
Senior Member
Joined: Jun 2010
Posts: 16,640
When you depress the horn button, that completes the ground for the horn relay to operate and sound the horn. Suggest you start by removing and cleaning all connection from battery negative post to vehicle and also to the sheet metal of your vehicle. One of them supplies the ground for the steering column , and you may find that is the cause of the problem. Let us know what you find , thanks.
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