M5R2 neutral safety switch??

92bird

Registered User
On 5 speed SC's, there is what appears to be a neutral safety switch. I know if you try to run codes with a code reader, and leave it in gear, it will give an error saying the car is not in neutral.

But what does the EEC use this info for?

The car will start in or out of gear, as long as the clutch pedal is depressed.

My only thought was possibly dashpot functions (the rate at which the engine returns to idle)

anyone?

Jeramie
 
If the neutral safety switch is bypassed it will start with or without the clutch engaged. Mine went out and sometimes would take several attempts to just get it to start so I just bypassed it. I am showing an occasional CEL but never knew that could relate to the switch being bad, or in my case bypassed. I dont really think it would have any effect on the way the engine actually runs or even idles since mine runs great even with the CEL.
 
That's wierd. There is a switch on the clutch pedal too. So you are saying if I were to bypass the netural switch on the transmission case, that it overrides the clutch pedal switch??

I'm trying to figure out how it works, because I am replacing the M5R2 with an automatic.

Jeramie
 
The automatics use a jumper on the clutch interlock switch, which i kept when i converted my explorer to manual and it allows for it to be started in gear:eek:. So if you use the jumper on the pedal switch it should override the one on the transmission.
 
I believe the EEC makes a slight adjustment when the clutch is not engaged.

The Clutch pedal position sensor and Neutral safety switch work in conjunction with eachother, they share the same wiring .. so when one or the other is switched in the closed position, it will send a signal to the EEC to let it know that it is in the Park / neutral position, or that the clutch is not engaged.

Im much more familuar with the 4r70w SC's .. one these, the Neutral safety switch is the Manual Lever position selector .. not sure how this works with the AOD.

- Dan
 
Yea, I'm putting a 4R70W in my '92, using a stand alone transmission control unit.

Hmm, I'll have to dig out the EVTM and figure this one out.

Jeramie
 
Blah...

On a 5spd car, there are TWO neutral switches, one on the transmission and one on the Clutch pedal.. they are closed when ever the shifter is in the Neutral position, or the clutch pedal is Depressed and Open other wise..

NOW the Clutch pedal has a Starter interrupt circuit which does just as the name implies, where as on a AOD car that same circuit also does the Neutral/drive switch function for the EEC.. Which has a spice on the transmission side of the tranny harness, on the switched side of the Neutral park switch circuit.. that then goes back to Pin #30 (on both 5spd and autos) which is labeled NDS :)
also Pin #30 (NDS) looks for a GROUND to see if it's in Park/Neutral.. which is one reason (of 2 i know of) that the start sileniod on the fender Diode in it, specially on Automatic cars.. on 5spd, it's an ABS only thing (reason 2) and on the 5spd, Pin #30 (NDS) gets it's ground signal from the Signal return Pin on the EEC (sorry forget the pin#)

And from testing on my '91 XR7 (5.0L, Automatic) and against some well known EEC turner on there, i have found that the EEC does alter Timing and Idle speed (only did it at idle) when the EEC sense it was in `park' it had like a 800-850 idle, and like 25-30 degrees of advance timing, i pulled the Red w/Blue wire off the start Sileniod (fender one) and the Idle dropped @200rpms and Timing dropped to Near Based timing (Base at the time was 10degree, and it went down to like 11-12degrees??) Also Had the ABS light come on when i disconnected that wire :p This May be totally different with a 3.8SC 5spd computer, since this was done on a 5.0L Auto computer (L1C, AKA modified SC EEC so rumors have been told, if they are still true today i don't know)

Also the Hole dash pot thing may be it too.. it may have different programs when decelerating in gear as awhile as `freewheeling'/out of gear..


More info then you needed? confused yah?? :) Sorry when i did my 5spd swap on my '91 like 5-6 years ago.. i wanted to know EXACTLY what each circuit did and how it was different between the 5spd and Auto, Anal, yes, but i wanted to do it RIGHT :)
 
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VERY good info, thank you..!!

On my EEC Tuner software, there are two different idle adjustments. One for drive, and one for neutral. I assumed these were for the auto trans only so I've always just made sure they were the same.

What I need to do is change the two speeds and see if the idle changes when I take the 5 sp out of gear. That would be kick ~~~ if it did, because then I could program it to add a couple hundred rpm when the 4R70W is put into gear.

I'll hafta try that tomorrow.

Jeramie
 
Correction is needed.

On my Post i need to correct something..

The Neutral Drive Switch (NDS) Input is Pin # 30 on the EEC-IV.. not Pin # 31 that i had above.. (and will correct in time)

Sorry About this.. I was just going off the top of my head. and being it's been awhile since i needed to REMEMBER that info...

 
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I do not know how your controller works.. BUT if it has a Ground output (or even positive, since that can be converted over VIA a transistor) when in Park or Neutral.. Then hooking up that circuit would work then..
 
On my 94 5 speed if I bypass just the starter interupt the car WILL START in gear for all its worth

Yes, mine does this, too.

If I touch the starter terminal to the power post, on the solenoid, with a screwdriver then the starter turns over regardless of clutch or gear position.
 
If the neutral safety switch is bypassed it will start with or without the clutch engaged. Mine went out and sometimes would take several attempts to just get it to start so I just bypassed it. I am showing an occasional CEL but never knew that could relate to the switch being bad, or in my case bypassed. I dont really think it would have any effect on the way the engine actually runs or even idles since mine runs great even with the CEL.
Any chance you could send me an email on how to do this? Please and Thank you! stevodev16@hotmail.com
 
I never really put any thought into this before because I didn't know the M5R2 had its own neutral switch, but did Ford put that switch in there to prevent an over-rev if the shifter is put into neutral, without using the clutch, while using the cruise control?
 
I could be wrong but I can't remember anything electrical plugged into mine is it different on a 90 it's been several years since I had mine out but I've had my 97 lx out much more recently and I know that one sadly all to well but for the life of me I can't thing of a plug or sensor on my 90 5 speed... Not even a place for anything to plug anything in
 
My 3 sold in Canada M5R2 cars only have a 2 wire b/u switch.
Possibly the switch you have or are seeing is used for the seat belt system on sold in U.S. cars?

I think the 89's only have a a boost bypass solonoid that is activated by the b/u switch also.

Norm L. has a good point too. I never thought about that before.
 
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