A speed control (cruise control) indicator light in place of the "check oil" light (topmost one on the right-hand stack of 5 lights). I don't have the oil pressure sender so the existing light is useless to me. I made this image up and I plan to print it on transparency film. I have an entire spare base instrument cluster, so I have something to experiment with:
The trick will be finding out which circuit will light the lamp. It's not obvious from looking at the EVTM, but perhaps the shop manuals will yield some insight.
Edit: according to the shop manuals you can't use a test light to test the amplifier circuits as the current draw will damage its internals. It looks like I'll have to use a relay to trip the light, but that's ok. Maybe next weekend when I'm feeling better I'll do some investigation.
After some tweaks I printed the image (which I actually made in CorelDraw) onto Avery clear sticker film. I also put cellophane on part of the back of it so no dust would stick to the part that light would shine through. This is how it looks on my guinea-pig console (pulled ages ago from a V6 '85):
I also updated the image above so you have what I have...
wow, you and your clear avery sticky back paper bring back memories for me. One day i NEEDED to be able to white letters on clear avery paper.
I quickly learned it cant be done,, go figure bill gates!! Imagine being me asking the people at staples and office max if they had white printer ink. All i was trying to do was make lables for these wire wrap connector blocks in a telephone office instead of ink stamping all 2016 pairs.
The paper was to be stuck to a black object so the white ink would stand out.
sorry,back to the topic.
I think this is actually a great idea. Ill stare at the wiring diagrams and see what i think will work. There are no relays to power the cruise at all, its all contained within the cruise module up near your left foot. In there would be the place to tap power and branch it to the dash. I would like to think that a simple parallel branch circuit would be enough to power a bulb in the dash when you press the on button.
The main power feed to the cruise amplifier is the white pink wire cabled to the six pin connector.
The wire i think would be best suited for this light to come on is the Light Blue/ black located on the six pin connector as well.
When the On button is depressed, this wire becomes live battery power and holds battery power until the off is depressed or the car is turned off.
Nice idea, let me know what diagrams you need, i may be right behind you on this mod.
Long story short,,,,,,,,,,,
run a wire from the light blue black wire in either the steering column or the amplifire up to the light bulb in the dash and then provide yourself with a ground jumper near by to chassis.
You could get far more creative by using your existing light bulb socket. I would first trace the flex print out completely and make sure is is an isolated run with no parallel branches. I would then the connect the black light blue wire up to the cluster connecter. Next i would trace backwards the ground side of that socket and make sure it is landing in an area common to other bulbs (duhh, probably is). Install bulb and test.
I would be very leary of doing it like this for the simple reason that you may back feed power to the cluster that you dont want and cause problems. most of the power on the cluster is 5v so expect a pretty bright light. you may just want to use an isolated bulb and socket with its own connections such that your new bulb simply sits in the hole you have reserved for "speed cont".
I would also think something along the lines of a 12v LED would be best becaue it would draw less current. Since we are talking about branchign a circuit out to an indicator lamp,, this lower current draw might be the best way to go and would have less of an effect on the amplifier.
That's nice work, boys.
I've already pulled the cluster out and snapped a wire lead in to the correct pin on the cluster connector. I checked the circuit as well as the EVTM, and it's isolated. The ground is common, but as you mentioned I need to check the voltage. The bulb itself is in the "low oil" socket, which according to pp.128-129 of the EVTM, takes 12V, so voltage shouldn't be a problem for a standard 194 bulb. That said, I remember reading in a manual (the Helm one?) that current draw is dangerous to the cruise amplifier, so I figure I need some sort of low-draw (relay-driven?) circuit that could trip the light. So at this point I have the bulb in, and its power wire coiled up and ready to connect to something.
couldn't you set up some sort of switch in the wheel that is triggered by the cruise button?
That would be easy, but not really right. For instance, if I'm driving with the cruise on and I tap the brakes, the light should go off. The cruise module really has to drive the light.
I have a spare relay (actually for my Explorer) and according to my calculations it should draw 153mA under 12V. The trick is figuring out how to use it. It looks like the cruise module uses either current draw or a voltage change (internal voltage divider circuit?) to determine which switch is pressed, so I can't just attach the relay to the LB/BK wire. I'm wondering if a simple TTL buffer chip would do the trick. Heck, a transistor switch circuit might even work. I'll have to dig out my old college EE book. One problem I forsee might be that I would expect the wire to still hold 12V even if I tap the brakes, since Resume has to work.
You can find anything on the net...
http://www.rason.org/Projects/transwit/transwit.htm
http://www.kpsec.freeuk.com/trancirc.htm
I'm just not convinced that the LB/BK wire is the right one. Any ideas?
I never used cruise in a ford, but in my step moms grand prix it stays on untill you flip off the switch, it doesnt function once u hit the brakes but you just hit resume and away it goes, so you want it to light only when its functioning. Thats why I assumed a switch would work.
Nice !!! I love mods that appear to be factory.Again,Nice !!!
I didn't put whole lot of thinking in to this,but why not just tap the hot side of the resume switch? I would think that would light the light,every time cruise is on.
The test proceedure in the shop manual has you hook +12v to the orange/yellow wire #144 to the servo modulating valve when testing the servo.
See if you can get your meter on this wire. Hopefully it will only go to +12v when the amplifier is on.
Whether the amplifier circuit can support the extra current load of a bulb on it I don't know. Does a bulb draw more current than a relay?
The amplifier has three states: Off, ON and STANDBY.
I've already figured out a circuit (with some help) that will minimize current draw. I can use a NPN transistor to drive a relay, which will trip the light. Current draw from the transistor will be ~2mA, which should be fine (I would think). I might look for a transistor with a higher beta value which would lower the draw even more.
EDIT: I have to use an NPN transistor, but otherwise my breadboard circuit is working. Now I just have to connect it to the car and try it. Maybe tomorrow...
Very cool, factory style mods are the s**t. I can't wait to see it when it's finished. :hick:
Im not really sure why your going about it like you are but sounds easy enough.
An LED in place of the bulb would glow plenty well enough i would think to illuminate the cruise illustration you have.
I was thinking that if you parallel off the wire i mention and run that up to your + bulb socket,, then your socket already provides the ground. (since you already investigated and answered my previous question)
when you press on, power is delivered through the wire i mentioned to the 6 pin connector. power will also be delivered to the bulb. After thinking about it, I do not think the current draw will be an issue, the servo will draw what it needs and so will the amplifier due to the amplifiers internal electronics.
both are 12v battery source fused at a decent rating so i think a bulb branch circuit would be an option. when you tap the brake, the bulb and the cruise will go on into a holding but not actually off pattern. when the resume ishiznit, the light and the cruise should come back on. This could be an unwanted feature in your design but i would not mind it myself, it would remind me to resume.
Drilling a hole in the switch for an led is out of the question and i would not ever attempt it. there just isnt enough elbow room inside the switch for that stuff in a home made fashion.
I'll assume your getting the bias volage from one of the cruise leads, correct? maybe i should ask how your wiring the transiter,, common base/emitter/collector ?
your VCC is from what source
your bias is from what source
if you dont mind my saying,, its sounds like your idea is fine but it might be over complicating things so keep your options open for simple solutions to compliated problems.
Nope and nope.
The LB/BK wire is floating (not hooked to anything) when none of the cruise buttons are pushed. The ON is a momentary contact. It only stays made as long as you are pushing the button.
When the ON is pushed the voltage supplied is not directly from the battery. It coming THROUGH the horn relay coil. The yellow/light blue wire coming into the horn swt and speed control swt is the wire you ground to blow the horn.
your yellow wire came up back on my curise thread and we found the colors did not agree with the evtm or shop manual (yours and mine). I had to follow my shop manual and ignore the evtm. There were a couple other wires as well with conflicting color coding.
Tested my cruise today. Pushed the ON before I started the car.
Started up and drove up to 40mph. Pushed SET/ACCEL and nothing, no cruise.
Pushed ON then SET/ACCEL and cruise is working.
Conclusion: the ON doesn't stay made until you push OFF.
Nothing really complicated, just saturating an NPN when the input goes high (forgive my rough paint tool drawing). I'm driving a relay to trip the light, note the protection diode (and its orientation).
well duhhh, your not triggering anything with the car off:D
I just tested my cruise also.
with the car running............
from a dead stop......
I press on.........
I drive for 4 miles and press set/accel.........
Cruise comes on.
with the car running .......
driving about 10mph..........
i press on...........
i drive for a mile.........
press set accel..........
Cruise comes on.
What does this tell you?
I know that one of the wires at the amplifier is being held high 12v when on is pressed and the car running. We can figure out which one it is but thats the one that would be best suited for a parallel branch. It makes perfect sense at the moment,, perhaps later it wont but for now, it does.
what input?
in that common emitter setup, youll have about 1.2ohms C-E when the input goes high (depending on the relay windings) but how high are we talking and from what source? Also, i dont understand the parallel 4.7k to the E either.
I assume your dissipating heat at the base and the parallel branch to the emitter but i can udnerstand why. You said you were going to use a low nput source ,,i thought. maybe im wrong.
Did you ever find the wire i mentioned that holds power to the amplifier when on is pressed? Im not talking about the servo here, never have been either. The servo is a whole different ball game and operates based on vac pres and moving a wiper which changes the internal resistance which then coordinates amplifier values in parallel with the coast / set accel / resume resistor pack in the right hand button switch assembly.
Great thread,, Great Idea!!! I thought about it alot today while on the road.
Lets see if I remember this right. To turn that transister on you need to forward bias the base to emitter junction and reverse bias the base to collector junction.
With a +12v input on the 470 ohm resister the two resisters are a voltage divider. It makes the base more positive than the emitter and more negative than the collector. Thus turning on the transister.
I am totally incorrect.
I was unable to utilize any wire on the amplifier as a light bulb trigger when the on is pressed.
And,, to add to the humor, when i put a test light from the wire i mentioned to ground,, and pressed "ON",,, the horn blew.:D duhh!!
I tried taking a crack at it but I'm having a hard time finding the speed control amplifier. Does anyone know where it's located and/or an easy way to get to it? I want to connect a voltmeter to the orange/yellow wire to see how it behaves when I exercise the cruise functions.
Bump. Can anyone point me to where the CC amplifier is? I want to take a crack at it but it's not obvious from the EVTM where the amplifier is.
I'm pretty sure that's the unit I was futzing around with last summer troubleshooting my cruise. Under the dash in the driver's side footwell. Pull off that black plastic cover under the steering column, and its kinda up in there gotta look for it, plastic box abotu 3" square by maybe an inch thick, two wide plugs going into it side by side.
That's the part,alright.It can be a bear to get to also.I remember pulling one for a member here off of my old parts car.No fun in that task.
It's been over a year since I posted on this, but I finally got around to building the simple transistor circuit. The power wire will be split, one going to the relay and one to +12V, since the only connectors I could scrounge were a pair of two-connector ones (they're deliberately reversed so a misconnection is impossible). It's supposed to be a nice day tomorrow, so I might try installing it.
The wires don't go straight to the circuit board, since I didn't want to risk them being pulled out. Inside the box they're spliced with shrink-tube crimp connectors to the wires that actually go to the circuit board, with shrink tube put over those. The circuit board is held to the case with a mounting screw+nylon spacer. So this should be pretty bulletproof. My only concern is the current draw from the speed control circuit. I don't think it will be too much, but it's hard to say. According to the shop manual, we must NOT use a simple test light as the current draw will be too high and would fry the speed control module -- hence the transistor+relay design (though the relay might be overkill).
It's been over a year since I posted on this, but I finally got around to building the simple transistor circuit. It's supposed to be a nice day tomorrow, so I might try installing it.
The wires don't go straight to the circuit board, since I didn't want to risk them being pulled out. Inside the box they're spliced with shrink-tube crimp connectors to the wires that actually go to the circuit board, with shrink tube put over those. So this should be pretty bulletproof.
Why bother with a relay and bulb? Just use an LED, they only draw 20mA or so, probably less than the relay coil.
I wanted to use the stock dash position, which takes a bulb. I wouldn't want to forget to put an LED in and accidentally blow the speed control circuit.
I intended to finish it today, but only got partially finished. I first wanted to fix the fan speeds from my 1997 rewiring project. That part is done, at least; I put in an interior relay block from a 1990's Taurus under the steering column. It has one large relay and six smaller ones, and I'm using the large one as the blower motor Hi bypass relay. I found what was wired incorrectly, and now all four fan speed settings are working nicely. As a bonus I put in a new fan switch and a ground block so I won't have to cut any wires anymore to get a low-current ground.
I have the speed control module I made installed and wired to one of the smaller relays, but I haven't connected it to the speed control amplifier yet. When I tested the Signal IN, though, I found a problem: I must have plugged the connector in the wrong pin on the instrument cluster, because my Low Fuel light comes on instead :rollin:
I'll have to pull the instrument cluster to switch to the correct pin, but I need to tighten up one of the bulbs anyway. So it will be at least another afternoon's work before I can complete this mod, but I'm almost there.
Well, I got the dash squared away, but now I'm having trouble at the last part -- getting the speed control amp to trigger it. So far, this is what my testing showed:
While stopped:
144 O/Y: 12V
145 GY/BK: 12V
146 W/PK: 12V
147 P/LB Floating
148 Y/R ~3.9V
149 BR/LG ~7.4V
While driving and testing the cruise, etc., the voltage on 147 P/LB seemed to closely track with my speed, for instance ~0.5V @ 25mph, ~0.6V @ 30mph, etc. I didn't try any of the others while driving, that would have been a lot of trips around the block :hick:
I then decided to take the amplifier apart just to see what it looked like (pictures attached). I noticed that there's an extra pin labeled Q3-C TP. It is apparently a test point for the collector of transistor Q3 on the circuit board. I don't know the significance, but driving showed that it would drop to near ground when the cruise was giving the car gas and would float around 40mV otherwise.
I suppose I could try to build a circuit diagram from the pictures and try to see if there's anything I can tap, but I don't know what the chip does.
Edit: I haven't found a datasheet yet, but I found this description of a slightly different (newer?) version:
http://translate.google.com/translate?hl=en&sl=pl&u=http://www.elektroda.pl/rtvforum/topic935585.html&ei=-W5JSoi6AaCY8wSfpOWTDQ&sa=X&oi=translate&resnum=9&ct=result&prev=/search%3Fq%3D%252214a607%2522%26hl%3Den%26client%3Dfirefox-a%26rls%3Dorg.mozilla:en-US:official
I took some better pictures and tried to make a circuit diagram of the speed control amplifier in Visio. The transistors are marked 10-05, M+ (Motorola logo), EBCK. I did a Google search on "Transistor EBCK" and all the results were NPN transistors, so I assumed that they're also NPN. I also removed redundant capacitors from the diagram (there are multiple caps connecting the chip's pin 13 to ground in various places). Otherwise, I *think* it's accurate; I spent quite some time with it, at least. Without the chip datasheet I'm not sure what to do short of lots of experimenting, but I'm wondering if anyone on the forum has any insights...
these threads should be helpful as well.
I have a couple of amps on hand of pre89. I noticed even the two i have of the same year are not exactly alike. dont ask why,, I dont know.
http://www.foxtbirdcougarforums.com/showthread.php?t=17452
http://www.foxtbirdcougarforums.com/showthread.php?t=14879&highlight=cruise+control
Well, I finally figured it out and got it working, but first let me say...OH MY GOD, WHAT A PAIN IN THE A**. This is NOT for the faint-of-heart. If I knew how hard this would be, I never would have started it.
The key signals to read are pins 21 and 22 from the chip. When the cruise is on and active, each pin sends PWM (pulse width modulated) signals to transistors Q2 and Q1, respectively. The signals have only a 1V amplitude (varying between ground and +1V), so you can't use standard TTL digital logic chips out of the box. Nevertheless, the idea here is, if EITHER line is producing ANY pulses, you want to turn on a light. Pulses only happen when the module is actively managing your speed. If you tap the brakes, turn it off, hold coast, or go significantly over the set speed (either by jumping on the gas or going down a hill), the pulses stop.
How did I find that out? I bought a two-channel USB oscilloscope that I could plug into my laptop. I connected the probes to the naked board (two test points at a time), put the laptop on the passenger seat next to me, and did some driving. Every few miles I'd pull over somewhere, switch to new test points, and drive some more. Eventually I tested pins 21 and 22 and saw what they did when the cruise was managing my speed.
Knowing what to read and actually doing it are NOT the same thing, especially for someone who isn't an electrical engineer. I've had two electronics courses as part of the Physics course load, but I'm trained to approach electronics from first principles, not from a higher-level circuit design standpoint. On the one hand, this was a real learning experience for me, but on the other hand it was a really painful week.
I have pictures to post, but the short of it is that I'm using an op-amp as a comparator, where I combine the two signals and compare them to a reference 0.5V. To keep the light from flickering I use a capacitor to make the op-amp find the peak signal, and I use a 555 timer and a pair of transistors to periodically discharge the capacitor (otherwise, as I found, once the light goes on it stays on, to the point that if I shut the car off, go inside for an hour and start it again, the light immediately comes back on since the capacitor is still charged).
Once again, let me say that this is NOT for the faint-of-heart. I went with a daughterboard design that fits inside the speed control amplifier module. It's a very tight fit, with a thin piece of cardboard insulating the two boards. Nevertheless, here are some tips for the adventurous (or suicidal):
1. Watch for short-circuits! There's a lot to fit in a small space on your board, and when you try to squeeze everything in the amplifier casing things can bend and touch other components (resistors, capacitors, transistors, etc.) Be very diligent in looking for any potential for shorts.
2. Check and recheck your solder joins, then check them again. I would have finished a day early had it not been for a flaky ground to the op-amp chip. If you're using any solid (rather than braided) wire, be especially careful as solder won't want to adhere well.
3. Use braided wire to connect to the main board. I lost count of how many times the solid wire would break when I manipulated the two boards. Only four wires connect the two boards: power, ground, and the two signal wires from Q1-base and Q2-base. It's harder to poke braided wires through the holes alongside the components, but worth it.
4. Come up with a bench-testing strategy. A 9V battery will do for a power source to a point, but the boards will drain it quickly. I eventually switched to a power pack to a CD player that gives me 9V. The speed control circuit will run on only 9V, that's all you need. The major things to test are power points, grounds, the 555 output, the +0.5V reference voltage, transistor outputs, the op-amp output, etc. At least you'll have a working circuit design.
5. BE PATIENT!!! I can't stress this enough. It's a PITA to put the speed control amp in the car, road test, take it back out again, make a change, bench test, and then repeat over and over again. You can bench-test this. Make sure that if you provide 1.5V to Q1-base or Q2-base you get a high output from the op-amp, and low output in all other cases. If it fails that test, don't bother testing in the car, assuming that you have a decent bench power supply (read: not a dead 9V battery). Test as much as you can before road testing, then do static testing with the amp in the car and the key on. Take your time, whether it's soldering or any other part of the process. You'll go insane if you don't and you find that you can't get it working.
6. USE AT YOUR OWN RISK. Gee whiz, do I even need to say this?
7. Most op-amp chips require +Vcc and -Vcc to operate, NOT, repeat, NOT, simply power and ground!!! That said, I used an LM324N quad op-amp chip, and I was VERY lucky to have it handy. I only needed one of the four op-amps on the chip and could leave the other three unconnected, but the MAJOR benefit is that this chip operates off standard power and ground. The moral is: make SURE to check your op-amp chip's power requirements. As for the other components, I deliberately chose resistors with high impedance to make this a low-current design, but for reference, the PNP transistor is a 2N3906, the NPN transistor is a 2N3904, and the two diodes are both 1N914. They're standard parts that you'll have zero trouble obtaining.
Okay, I have six pictures. They were taken at various stages in development, so don't pay much attention to the filenames. This was a painful, trial-and-error process over the better part of the week. I'm still not "finished", but the electronic part is. The only thing left for me is making the green light aesthetically pleasing. The white LED I have in the dash is WAY too bright, and standard bulbs are giving me a light that looks more amber than green. I have some green acrylic to play with, but the hard part is definitely finished. I'm just glad that I don't have to do this again.
Second set of pics...
I don't know if anyone's still interested in this, but here is final chapter of my speed control dash mod.
First, I removed the single-bulb white LED that was way too bright (the one on the left in the image), and replaced it with one with multiple bulbs. The new one has three small ones along the sides and one large one in the center. You might think that it would be even worse, even brighter than before, but there's a catch: it was defective. I had four, but for one of them, the big center LED wouldn't light: only the three side ones would. So I was getting a soft, white light. Just to be sure I put it in my spare instrument cluster to see what the effect looked like. I liked what I saw, and decided to go with it. If nothing else, the side-facing LED's seemed to result in much better light diffusion.
The second part was to use some green acrylic behind my "SPEED CONTROL" indicator on page 1 of this thread. I had a set of color samples from Ridout Plastics and cut out a piece of the 2092 green one (that's not a crack in the middle of it in the picture, it's just a fold in my comforter ;) ). Anyhow, I cut the section so it would fit tightly in the cluster in front of the bulb.
After switching the bulb and adding the extra green filter, the result was a gorgeous, deep green, that was neither too bright nor too dark. It truly looks factory, indeed I couldn't have hoped for it to be any more perfect. If I ever have to replace the LED, I suppose I could stick something in the replacement to break the center bulb so only the sides would light (or maybe just stick a piece of black ABS plastic on it), but I'm hoping that this one will last a good, long time.
So that's the end of the mod, and of the story. I can't describe how glad I am that it's over, and finally ended well.
One more picture, showing the green acrylic in front of the LED.
Edit: and another showing the light when on (it's simulated, I wasn't actually moving).
Just a small update...I've had some stability issues with the circuit (light staying on, mainly) and made some small design changes. When I get my main PC back up and running I'll put together a proper schematic in Visio. The short of it, though is:
- replaced one 15k resistor with a 100k trimmer pot so I could adjust the reference voltage (up to 0.6V)
- put a 10uF capacitor between the reference voltage and ground to remove noise from it
- put a diode between the 1M resistor and Cpeak so current can only go toward the NPN transistor.
Whats with the 7seg displays on the lower right side of the column?
It's an LED voltmeter I installed. I swapped in a TC panel so it would have a cutout and put the voltmeter on a piece of black ABS plastic I had.
I was hoping it read the jigawats from the flux capacitor.
In case anyone's interested, this is the final schematic for the speed control indicator mod. The variable resistor in the bottom right is used for adjusting the threshold voltage so that the light is off when it's supposed to be off and on when it's supposed to be on. Generally, the threshold voltage should be around 0.6-0.7V, but your mileage may vary.
I found that, while the above buttstuffog circuit works, it's very unreliable. I was constantly having to adjust the threshold voltage to keep the light from either staying on or from flickering. Finally I threw my hands up and decided on a complete redesign. The result is below.
This is a 100% digital circuit, and so far it's working flawlessly. The inputs and outputs are exactly the same as before.
One thing that helped a lot: I put this in a separate case, and I used a clear case from sparkfun.com. I also have a couple of LED's on the board: one just to show that it's getting power and another to show the state of the OUT circuit. This made testing a lot easier. It connects to the speed control amplifier through Ford standard radio connectors, since they're easy to get, and it makes it easy to remove.