Got a real head scratcher here. Bear with me it takes a bit of telling.

Yesterday when I started the truck (97 F150) the ABS light would come on and blink. I also could not shift out of park. I was able to shift by turning key to on, shifting to neutral, starting and then shifting into gear.

I read around here and found it was probably a fuse (#13). Sure enough it was blown. When I replaced it I had the battery out charging, so I couldn't test to see if that fixed it.

When I put the battery back in, and tried to start, all my dash lights were dim and I didn't hear any injectors or fuel pump turn on. After trying to start a few times I soon got no lights or any power at all, the starter solenoid didn't even click. When I checked the battery, the + terminal was pretty hot. Then I heard a hiss and saw a puff of smoke from over by the master cylinder. Checking the brake fluid pressure sensor (not the fluid level sensor) it too was very hot. Apparently a short in the sensor. I disconnected the sensor, and still same thing with dim lights and hot terminal.

I measured the resistance across the battery cables, and I get infinite..until I turn the key to on. Then I measure between 20 and 70 ohms.

If you've read through all my , thank you.

Does anyone have any idea how these problems are related? Should I get such a low resistance reading when I turn the key to on? This all happened at once, so they are all likely related. If the pressure sensor was shorted in the beginning (when fuse 13 blew), then it should have blown again when I replaced it, but it didn't. If the sensor was the short, the truck should have started when I disconnected it (albeit with a check engine light), but the short remains.

I was supposed to move out to college tomorrow, so I'll be troubleshooting all day. Any insight anyone can render would be great. I'll update anything I find out.

 

hmmmm... someone didn't get his recall 05S28 done....

 

It's difficult to pick anything out of your discription as a cause.
First, a resistance measurement at this point is of little value.
Getting some perspective first; does the motor crank normal or slow?
What happens with just the ignition to 'run'?
Have to begin by sorting out what happens when.
Lights dim at cranking etc.
The starter draws a high amount of amperage and could be the cause of the cable terminal getting hot.
The rest of the circuitry wireing is much smaller and would burn from a short or blow a fuse.
Bottom line is you have to get a handle on what is happpeng before you can repair.
Not much help to you.
Good luck.

 

That recall seems to be for the 2000 model year; mine is a '97.

I figured it out.

Turns out the brake pressure sensor blew it's internal seals and leaked brake fluid all over the sensor electronics. This then, shorted and caused the harness connector to partially melt creating another short. When I disconnected the sensor the short still existed in the connector, so that's why it didn't solve the problem.

I clipped off the connector, everything worked again - no shorts. I ran to Victory (junkyard) and found an F150 with that sensor and connector already removed. Seems like this has happened to someone before. I grabbed one from a Explorer, replaced the sensor and crimped on a new connector.

Problem solved.

Don't know if the short had anything to do with fuse 13, but I'm kinda wondering why I didn't blow some fuse, somewhere.

 

Duh, that's what the recall was there to address. This has been a commonly known problem for at least 6 years. At least your truck didn't go up in flames. It covered a large range of model years including the 1997.

Contact your Ford dealer with your VIN and get it done properly.

 

Looked into the recall more thoroughly.

You're absolutely right, that's it to a T. I stand humbly corrected.

Well played sir.

 

In my reply I was thinking it sounded like the recall problem.
There have been some trucks and homes lost due to it happening in the middle of the night and at other times and places.
You lucky.
Good luck.

 

I'll bet it has.

Can't believe I watched it fail right in front of me.

Further I can't believe this wasn't fused to begin with.

I'll be thanken my lucky stars tonight...

 

Well, it was. Early on, it was on a 20A ALWAYS HOT circuit (97 & 98), then moved to a 15A ALWAYS HOT circuit for another year or three before it was moved to a lower rated fuse.

Unfortunately, 15 -20 amps was plenty of juice to start fires without ever blowing the fuse....

Good thing it's now safer. Keep the SCDS disconnected until the recall is performed.