NOS Dealer Installed CC FORD F2TZ-9A818-A

[Gary Lewis]

Just had to try this. Learned a new trick of embedding things in posts by ticking the "Message is in HTML Format" and wanted to see how useful embedding the info from the '96 EVTM would have been.

[evL]

Hello Gentlemen, I am in a bind and perhaps you folks could shed some light...

I have this exact Ford kit. I carefully and meticulously installed it. I got no cruise. So before blaming the module in the kit I went right to circuit 679, the GY/BK wire. Low and behold I have no VSS signal, no 3-4 volts at 30+ MPH at pin #3 on C216, the GY/BK wire. This is where I tapped in to provide the signal for the module in this kit.

This is on a 1995 Ford Bronco, 302 5.0, Manual Transmission, 8.8 rear end, and no stock cruise control. This vehicle is in perfect order and running condition. No codes. The speedometer works fine and as it should, no bouncing around. Odometer works fine. Though lack of a stock cruise control I do have the C216 plug on the left side of the engine compartment by the fender, closer to the firewall, close to OBDI and Anti-Lock brake test plugs, right where the cruise servo/amplifier assembly would be if the vehicle had one. My VSS is on top of the 8.8.

I have read and downloaded piles of info from the pros... Steve83 and Miesk5. Been all through fullsizebronco.com, supermotors.net, broncozone.com, diesel-dave.com, and others. In the instructions for this kit it mentions locating a gray 6 pin connector somewhere in the middle of the of the vehicle under the dash and tapping into the GY/BK wire there. I don't have that connector, or at least haven't found it. I figured all would be well tapping into the GY/BK wire on C216, right? Started checking if the other wires on C216 were doing what the should. And they do. i.e. 10 is a good ground, key to RUN I get 12v from 7 and 10, key off less than 20 ohms between 10 and 4, etc. etc...

I started chasing the GY/BK from C216 with strait pins. Got to splice S246, chased both sides to the fire wall, still nothing at 30 to 30+ mph. Gonna get on inside and take off from the firewall and see how I fare. So I am guessing I need to go strait to pin 7 on the PSOM perhaps. I am under the impression that one cannot just tap the VSS before the PSOM because the PSOM sends out the 8000 pulse deal? Maybe it's not 8000 but I think you know what I mean. Yes my test leads and multi-meter are in good repair. And I am better with auto electrical issues than other auto related items. But golly this has me stumped...

Any ideas would be great... Good Day.

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[Gary Lewis]

Welcome to the Bullnose Forum! I'm not going to chastise you for not creating a new thread in the New Users Start Here folder as I suspect you are just here to get your problem solved.

However, tacking this onto an old thread may not get you much help. We shall see.

Anyway, I wonder if because your truck has a manual transmission and had no speed control if the PSOM was programmed with the output on CKT 679 turned off. I don't have a 1995 EVTM, but my '95 EVTM shows the output going to both the Power Control Module and Speed Control Amplifier, as shown above. But maybe the PCM doesn't need the speed since it isn't controlling the transmission?

In the page below you can see the Enable PSOM Programming Connector. Perhaps you can find out how to go into programming mode and check to see if there is a box for Speed Control that needs to be checked? I don't know how to program the PSOM, but I was recently told there is an easy way to do so.

[Steve83]

evL wrote

This is on a 1995 Ford Bronco, 302 5.0, Manual Transmission, 8.8 rear end, and no stock cruise control. This vehicle is in perfect order and running condition. No codes. The speedometer works fine and as it should, no bouncing around. Odometer works fine. Though lack of a stock cruise control I do have the C216 plug on the left side of the engine compartment by the fender, closer to the firewall, close to OBDI and Anti-Lock brake test plugs, right where the cruise servo/amplifier assembly would be if the vehicle had one.

Pics of the kit you have & how you installed it would be helpful.  Refer to these & their captions:







Just because the engine bay harness has the servo connector, that DOESN'T mean that every other harness section has the mating wires.  It's conceivable that your dash harness does NOT contain all the wiring necessary to support cruise.  What trim level is the truck: XL, XLT, EB...?  Test continuity on the Gy/Bk wire from the servo connector to the PSOM connector.  A pass is <5 Ohms; 20 would be a fail.

[evL]

Hello Gary, I didn't get the email about the "New Users Start Here folder" until after I posted. And I didn't think the thread was to old with a first post of 03/01. Apologies...

Interesting take on the PSOM programming. Never thought of that. Odd though because 679 leaves pin 7 of the PSOM to connector C202, gotta find that, then splits at S246 and goes not only to the servo but to the PCM as well. So perhaps the signal is still needed even with a manual tranny??? Something to look into.
I think that programming connector you mention is the one that should be located under the glove box? The one used to set ones speed after different tires.? I thought that was all one could program to the PSOM as well.

And Steve the reason for no pics was because the pics on page one of this thread are exactly of the kit I have. As far as installation that was per the instructions in the kit. And thanks for the pics guys, I do have those and many more from your directory on Super Motors Steve. The trim package is XL, an ex Forest Service rig. Good point about the wiring harness. That very well could be. I'll have to do that test you mentioned. I just didn't want to rip take the dash and all apart just yet. but looks like we'll be getting into that soon.

[evL]

Ok rather than waiting for the weekend I removed the cluster after work and got to the PSOM. So Steve, I checked the continuity on the GY/BK wire from the servo connector to the PSOM connector. Flat zeros, so very much have great continuity. Glad for that. And another thing that confirmed that was when I checked for a speed signal at the servo connector a while back I got .15 v @ 35 mph. Well I checked for a speed signal tonight on the GY/BK wire about three inches from the PSOM plug and got .15 v @ 35 mph. So continuity is there.

So looks like Gary might be on to something because obviously my PSOM is not sending out a speed signal on circuit 679 GY/BK wire. That sucks... So guess I'll figure out how to program it. It's just that, as I mentioned, I've only read about doing the speed constant programing for it. I was under impression that was all one could do. Might hit up the dealership to see if I can learn more. But that's the hard place I am up against now. Gary, you were right...

[Gary Lewis]

Let's not assume I'm right just yet.  But, I think it is a good place to start.  However, like you I've only read of changing the speed multiplier to accommodate tire size differences.  But, who knows?

[Steve83]

evL wrote

...no VSS signal, no 3-4 volts at 30+ MPH at pin #3 on C216, the GY/BK wire.

evL wrote

...when I checked for a speed signal at the servo connector a while back I got .15 v @ 35 mph. Well I checked for a speed signal tonight on the GY/BK wire about three inches from the PSOM plug and got .15 v @ 35 mph.

So just to be clear...  You're not getting "NO signal" - you're getting "a lower voltage than you expect".  Right?  What kind of meter are you using?  For any AC signal other than 60Hz (household power), a true-RMS meter is required.

evL wrote

...obviously my PSOM is not sending out a speed signal on circuit 679 GY/BK wire.

It's not obvious to me, based on what you've posted.

evL wrote

So guess I'll figure out how to program it.

This caption contains everything I've ever learned about the PSOM, including most of what the service manual says about it:



In any case...
I highly recommend that you STOP fighting that antique cruise system, and just install the factory parts for the truck.  Browse a few JYs - they're VERY common & affordable, and hardly ever fail.  The '93-04 cruise system is significantly superior to most others anyway, due to its 1-MPH response to the ACCEL & COAST buttons.



The steering wheel takes just a little bit of effort, but it's worth it.  But it's better, easier, & probably cheaper to swap to a newer column (one whose clock spring is available), which will give you backlit buttons & the option to use the wheel-mounted radio controls.

[evL]

Hello Steve, Yes I am not getting any signal, or at least not the 3-4 volts and 30+ mph. I am using a GB [Gardner Bender] GDT-11 Digital Multimeter. Isn't a True RMS for accurately measuring standard [pure ac] sinusoidal waveforms? You mentioned AC signal. Now I might be completely off because I was measuring DC not AC. ???

I am not fighting this NOS Ford Cruise Kit. I am not getting a VSS signal. Be it this Ford Kit or Factory Parts both are going to need a VSS signal.

Anyhow off to read your first link...
https://www.supermotors.net/registry/media/76023

[Gary Lewis]

I think you may be onto something.  You won't see the full voltage of a pulsed signal with your meter on the DC scale.  At best you'll see an averaged voltage, meaning that a signal that has a 10% duty cycle pulse may read ~10% of the DC value.

I'll go to the shop again in a bit and look at my '96 EVTM to see what it says, if anything, about duty cycle.  But you might try reading it on the AC scale.

[evL]

I remember reading somewhere it was an AC voltage, I think a sine wave, from the rear differential to the PSOM but the PSOM puts out a different signal from pin 6. Regardless I'll check tomorrow.

[Gary Lewis]

That page from the 1996 EVTM, above, says the PSOM converts it to 8000 pulses per mile. So it isn't a DC voltage. Instead, it is probably something approaching a square wave, not a sine wave, since it is far easier with solid-state electronics to create an on/off signal than a shaped wave.

Surely the pulses are sufficiently narrow that the vehicle can do 150 MPH w/o the pulses running together. So if we assume 150 then at 30 you have a 20% duty cycle and your DC voltage might read something less than 1 volt, and maybe less if the duty cycle is less. But, many volt meters don't like pulses and give wonky results on the DC scale.

Your meter might give reasonable results on the AC scale, but it might not as these probably aren't sine waves and aren't coming at 50-60/second, which is what most meters expect.

I think the only way to truly know what you have is to look at the signal on a scope. But those are rare these days, and most don't run on batteries so you can't take them up to 30 MPH - unless you have a really long cord. However, the fact that your meter is seeing something is encouraging and says you have a signal. But I'd try it on the AC scale to see what you get.

[Steve83]

evL wrote

Isn't a True RMS for accurately measuring standard [pure ac] sinusoidal waveforms?

No, true-RMS is for measuring AC voltage or power on anything OTHER than a 60Hz sine wave.

evL wrote

Now I might be completely off because I was measuring DC not AC. ?

That's why you're not reading the signal that has probably been there the whole time.

Gary Lewis wrote

...on the DC scale.  At best you'll see an averaged voltage...

The average of an AC signal is only the DC offset, which is usually 0V (ground).  Duty cycle has no impact on the DC reading of an AC signal.

evL wrote

I remember reading somewhere it was an AC voltage, I think a sine wave, from the rear differential to the PSOM but the PSOM puts out a different signal from pin 6.

No, it's a Hall-effect sensor - not a simple inductor.  So it puts out a nearly-square wave.  The PSOM's output is probably slightly closer to square, but it doesn't really matter.  Use a true-RMS meter set to ACV.

[evL]

Great info guys...
Gonna find a True RMS meter and give it a go on AC...