Clutch pedal position switch.
 

Anybody had one actually fail? I've been reading old posts for an hour or so, and while it is often mentioned it is never the problem.

Here's the deal. One minute the truck (97, 2.3, manual) was fine. Shut it down and it would not turn over. Popped fuse #24 in the cab. Jumped the starter relay to get it home, but the relay is not the problem. Fuse 24 will pop every time I put the key to start with the clutch depressed. I traced power to and through the ignition switch...it's good. With a good fuse I can get power to the CPP switch, but I can not get power out of the CPP switch. Even with both the fuse and the switch jumpered. It's like it's just absorbing it.

So, back to the original question. Has anyone actually had the switch fail, or should I be looking for a short further down stream Only the starter solenoid and cable remain....don't really want to crawl under it in the rain, but I really hate buying $50 switches that don't fix the problem.

Any troubleshooting steps that I've missed? Any words of wisdom or advice?

Fuse blowing is indictive of a short. I've only heard once of a CPP switch failing, so it does happen, but not all that often.

First of all figure out why the fuse is blowing, then if the problem is still there, which I would expect it to be considering you found power at one side and not the other with the clutch depressed, then yes, I'd say it's the switch.

Yep....that's where I'm at. Guess I'll go get the switch tomorrow.

I had a similar problem at about 70 K miles - sometimes the engine would start off with no problem, sometimes it would start after pushing the clutch pedal all the way down (as far forward as it would go) and sometimes it just wouldn't start. I would wait a bit and it would start. Replaced the switch and solenoid (the solenoid wasn't very expensive) and haven't had a problem since.

That's good to know. The relay was the first thing I replaced. Been chasing wires ever since. I picked up the switch yesterday, going to go install it in a few minutes.

I just unplugged the switch at the peddle on my 84 so I could start it while holding one foot on the gas and the other on the brake. Maybe It's different then yours.

The newer trucks you have to jumper it to let it start without the switch plugged in. I prefer to be able to start it without the clutch depressed, with the truck in neutral, in any carbed truck on an incline. The parking brake just won't cut it sometimes, and you need your foot on the gas.

Ok....now I'm getting a little grumpy.

I've tested the ignition switch per page 149-02 of the 97 Ford service manual, the switch passed all checks. I've ohms and volt tested the wiring from the ignition switch to the fuse, from the fuse to the CPP, replaced the CPP, checked the wiring from the CPP to the starter relay, and replaced the starter relay. In other words.....every wire and component in that circuit has checked good or been replaced. I've also removed, cleaned and reinstalled the battery power and ground leads at the block, frame and starter.

I even went so far as to jump the fuse (#24) hoping to smoke whatever component is causing the short, and all it did was smoke my jumper. After that I puled apart the fuse panel itself to see if there was a wire crossed there and the ***** looks brand new.

I am at a complete loss for where to look next.......anybody got anything?

What else works off that fuse besides the clutch switch? I would look to that.

That's part of the problem....I can find nothing else on that fuse. On vehicles equipped with a passive anti-theft system the starter interrupt relay is powered off that fuse, but this truck is isn't a PATS truck.

Scott have you used your ohm meter to test for a short to ground in the wiring? by that I mean hook the ground lead to a good ground and the positive to different parts of your wiring harness. I will try to look at a wiring diagram when i get down to the shop tonight or tomorrow.

Yep. I've checked for continuity and ground at the ignition switch, fuse block, clutch switch and start relay.........just scratching my head.

I'm about to the point that I'll just hook up a jumper wire on the relay with a push button and forget about fixing it.

One thing to note, I believe disconnecting or otherwise jumpering the CPP switch may cause issues with the cruise control and clutch usage. Then again, I think most of us are smart enough not to hit the clutch when the cruise is on.

Well....this story ends on a positive note. The truck is fixed and starting/running fine.

The moral of the story is don't trust technology...or don't forget the old school.

The short of it is.....my DVOM lied to me. Knowing that I had already checked and or replaced every part of the system, I started over old school. Made myself up a jumper wire and started jumping each segment of wire from the ignition to the fuse to the CPP to the relay. The short is in the section of wire between the CPP and the starter relay.....probably at the factory splice through the firewall. Replaced that section of wire and all is well.

Thanks to all who put into this thread. I appreciate it. And to those with manual trannies......beware fuse #24. :)

Awesome glad to hear you figured it out!