Can Clutch Switch(M5OD) mimic dead Battery problem?

[JohnMcD348]

OK, for the past few weeks, I've had to depress the clutch a couple if times to get the Bronco to crank. I would depress the clutch, turn the key and nothing would happen. All I would get was hearing the fuel pump pressurize the system. I would keep the key turned, press the clutch again and it would crank right up.

Yesterday, I got to spend a couple of hours waiting for a tow truck. I got in the Bronco after a short drive and pressed the clutch, turned the key and nothing. Pressed the clutch again and Nothing. Pressed it again and NOTHING!!!!



This isn't how I wanted to spend my one day off.

OK, so I am speculating it has something to do with the switch/contact in the clutch pedal that makes it mandatory to press in the clutch to crank the engine. I noticed a couple of times when I tried to crank the engine and pressed the clutch in with the key turned that the RPM needle bounced hard, maybe up to 4K or higher. It was a quick movement and had I not been looking at it, would have never seen it. the whole thing is acting like a dead battery except that the radio, lights and everything else work fine. I tried jump starting it with the Ram and still nothing happened. No clicking, no turning over of the engine, nothing except the lights got a little brighter when it was hooked up to the Ram.

Any possibility of it also being the Starter solenoid instead? What's the best way for me to start looking/testing instead of just throwing parts at it? No corrosion on the battery to speak of. I really haven't had a chance to start looking into it yet but will hopefully if I am off on July4th.

Thanks All.

[TheUnforgiven]

Yes since the clutch interlock IS a starter interlock, it can keep the starter from engaging when you turn the key if it malfunctions.

The tach jumping is strange though. never heard of that one.

it could be the starter relay, but since the issue would be dependent upon the clutch being hit a couple times, i would start there.

bypass the clutch interlock and see what happens, it's only a couple wires. how, i am not exactly sure.

off topic: you couldn't find a couple of dudes to push the truck so you could pop-start it?

[JohnMcD348]

Naw. You would think being at a Lowe's, there would be plenty of people there to help. Just didn't feel like asking at that time of day. Besides, we have towing and roadside assist on our insurance. Might as well use it.

There was another Bronco I saw there with Wisconsin plates and the guy just looked at me and shook his head as he drove by. The F'er........

[Steve83]

All the Clutch Pedal Position switch does (to the starter circuit) is interrupt power between the ig.sw. and the starter relay when the CPP doesn't indicate the pedal is FULLY depressed. That might be because your carpet is folded down behind the pedal, preventing you from fully depressing it; or because the switch is maladjusted, and doesn't indicate the actual position; or because the switch is bad. To find out, remove the switch (slide the catch plate back and it falls off the rod), and operate it manually while testing continuity (Ohms, diode) between the proper terminals.

.

If it passes, check for 12V on the #1 R/LB wire with the key in START. If that passes, the fault may be in the starter relay. Jumper from the large REAR post to the small post; it should click solidly, and the starter should immediately engage the engine.

.

If not, the fault is in the starter.

[TheUnforgiven]

Originally Posted by Steve83

All the Clutch Pedal Position switch does (to the starter circuit) is interrupt power between the ig.sw. and the starter relay when the CPP doesn't indicate the pedal is FULLY depressed. That might be because your carpet is folded down behind the pedal, preventing you from fully depressing it; or because the switch is maladjusted, and doesn't indicate the actual position; or because the switch is bad. To find out, remove the switch (slide the catch plate back and it falls off the rod), and operate it manually while testing continuity (Ohms, diode) between the proper terminals.

.

If it passes, check for 12V on the #1 R/LB wire with the key in START. If that passes, the fault may be in the starter relay. Jumper from the large REAR post to the small post; it should click solidly, and the starter should immediately engage the engine.

.

If not, the fault is in the starter.

that really goes to show how simple the starting system is on these trucks.

[lonesomebob]

All Broncos are wired for the clutch switch. When an automatic is installed, they have a plug they put in the clutch switch socket of the wiring loom. Go to a junk yard and pull this plastic plug out of an automatic truck. Put it in the plug of your truck, and it completes the starting circuit, eliminating that switch. All you'll have to remember is to put your trans in neutral before starting, and you'll avoid another "Nanny State" device to protect you from yourself ;~)

[Steve83]

Originally Posted by lonesomebob

...it completes the starting circuit, eliminating that switch. All you'll have to remember is to put your trans in neutral before starting, and you'll avoid another "Nanny State" device to protect you from yourself

That will also interfere with the EEC's strategies for timing, fuel mix, idle control, and some others. These old EECs need the clutch switch to be open from the starter relay trigger most of the time, and connected only when the pedal is down.

In other words: fix it right - don't install the wrong part.

[TheUnforgiven]

Originally Posted by Steve83

That will also interfere with the EEC's strategies for timing, fuel mix, idle control, and some others. These old EECs need the clutch switch to be open from the starter relay trigger most of the time, and connected only when the pedal is down.

In other words: fix it right - don't install the wrong part.

would the EEC's that have automatic transmissions be programmed differently to compensate for this?

[Steve83]

Only E4OD & 4R70W. C6 & AOD use the same EEC as a stick, so they're wired to force the correct strategy.

[TheUnforgiven]

thank you

[lonesomebob]

Interesting, I converted to stick, don't know if there's a MAF computer for this application, and the only codes I've ever had are in regards to not getting signals from the auto tranny. Otherwise, runs great passes smog with a wide margin.

Originally Posted by Steve83

That will also interfere with the EEC's strategies for timing, fuel mix, idle control, and some others. These old EECs need the clutch switch to be open from the starter relay trigger most of the time, and connected only when the pedal is down.

In other words: fix it right - don't install the wrong part.

[JohnMcD348]

Originally Posted by Steve83

All the Clutch Pedal Position switch does (to the starter circuit) is interrupt power between the ig.sw. and the starter relay when the CPP doesn't indicate the pedal is FULLY depressed. That might be because your carpet is folded down behind the pedal, preventing you from fully depressing it; or because the switch is maladjusted, and doesn't indicate the actual position; or because the switch is bad. To find out, remove the switch (slide the catch plate back and it falls off the rod), and operate it manually while testing continuity (Ohms, diode) between the proper terminals.

.

If it passes, check for 12V on the #1 R/LB wire with the key in START. If that passes, the fault may be in the starter relay. Jumper from the large REAR post to the small post; it should click solidly, and the starter should immediately engage the engine.

.

If not, the fault is in the starter.

Thanks Bro. I'll tear into it first chance I get. I know it's not the carpet, there's nothing there but metal floor. I wonder if I may have over reached the switch by not having that cushion level there. I've heard the clutch squeaking for a few weeks and just assumed the pivot point needed to be lubed.

Stupid question. Which contacts do I need to check? I don't have Cruise control so I know #3 isn't necessary. #1&2 are obvious but where do I run to ground? Is it grounded off the body of the switch itself? ON the pin out, it gives the numbers 408, 32, 511. Do I need to know what these reference?

Have I told you how glad I am you're back?

[Mikey350]

This might be a little late to the party, but here's the CPP schematics from the '94 EVTM, it might help. ('92 should be the same)
Good Luck!


http://www.supermotors.net/registry/media/874104_1


http://www.supermotors.net/registry/media/874093_1

[Mikey350]

S%$& - duplicate post

[Steve83]

Originally Posted by JohnMcD348

I've heard the clutch squeaking for a few weeks and just assumed the pivot point needed to be lubed.

They probably do - no one ever does that maintenance. I prefer Teflon grease for that.

Originally Posted by JohnMcD348

Stupid question. Which contacts do I need to check? ... #1&2 are obvious but where do I run to ground? Is it grounded off the body of the switch itself?

If you're testing continuity (resistance) thru the switch, you don't ground anything - you test from one pin to the next (DISconnected). If you're testing power or voltage, ground one probe, and put the other on the back of the connector.

Originally Posted by JohnMcD348

...numbers 408, 32, 511. Do I need to know what these reference?

They're Ford's numbers (names) for those circuits.

[JBfab]

Just a heads up if the clutch switch, ignition actuating rod or the silinoid on the fender ever fails on you- put the truck in neutral, put the ebrake on, pop the hood and jump the two big terminals on the fender mounted silinoid with anything metal. If its not the starter it will fire right up, no need for a tow truck next time.

[JohnMcD348]

I tried the jumper trick and it acted like a dead battery. Tried jump starting it with the Ram and still nothing. I'll take the starter off Sunday when I'm off and get it tested.

[JohnMcD348]

Well, got the starter out and took it to Advance to get tested. Not only did it fail, it shorted out bad enough it caused the breaker in the store the machine was plugged into to trip. I picked up a new remanned one with the lifetime warranty using the discount codes and saved about $50(including core).

Interesting note I discovered. Apparently Ford changed from the spade connector to a sealed hard wired connection so I have to cut/splice/heat shrink the new connection.

[JohnMcD348]

OK, Replaced the starter. Took about 40 minutes total time from removal to reinstall. It cranks much quieter now. Much more than I remember it ever doing.

I do have to hit the clutch twice to gt it to crank though.

If I have the clutch pressed and turn the key, nothing happens. I leave the key turned and press the clutch again and it cranks like a new Bronco.

Could the clutch switch maybe have caused the problem with the starter? Either way, I have a lifetime warranty on it so I won't be out anything but a few minutes. But, if it could, I may as well replace the CPP switch also just to save some future grief. The starter solenoid was replaced a couple of years ago when I though that was a problem, only to find out the Neg- cable was nearly corroded through.

[TheUnforgiven]

i'd go to the junkyard and get another clutch interlock switch.

you are the first time i've ever heard about one failing, in any type of vehicle, ever.