Dash sensor modules schematic

[WayneG]

Most of the parts are in.
Final circuit is ready for testing in copper.
I will make a photo mask next week and make 4 PC boards.
I will populate one of them and run tests. If all is OK, then I will build 3 more to send out for testing. I wish the weather was better for live testing!
The schematic and board files in my web site have been updated:
http://theouterlimits.ws/projects/ai...sorModule.html

[bkahler]

VERY Impressive!

[Keyair]

Looking good Wayne!
I would think the best way to reinstall this would be to add plugs to it.
I think you used Molex on your dash. What plugs do I need, where do you get them and what tools do you need to crimp the pins etc?

[WayneG]

I am including a 10 pin mating plug with about 24" to 36" of wire to spice into the original wiring.
In case there is a need to swap out the module, you dont need to cut and splice wires again

[cole3444]

If you have any extras I would love to get a module from you for my 83 310 and get my dash back to normal. Glad their is someone that can design things like this for people like me. How hard is it to change bulbs to LED on the dash so I can see at night while it is apart. Thanks again Jim

[WayneG]

I will start a list of who wants a module, but first I need to finish up testing and start assembling more boards.

I need to make a tank to simulate the washer fluid and coolant tanks to see how the circuit responds.
I am not sure how to test the water in fuel circuit. That is a diesel engine sensor that I dont have, and have no clue how to setup a test for it?

I just finished the first board and it needs some tweaking. I made 8 circuit boards but only 3 of them are usable due to the photo mask was not dark enough and too much copper was etched off. I think I have the process ready for a new batch, but I will wait until testing is done in case I need to change the design.

For making the circuit boards, I found out, after the fact, that there is a fairly cheap service that will make the boards for you at about $5 a square inch for 3 boards, that would be about $25 a bare board with holes drilled!
The hitch is that you need the drawings is a special format and the learning curve and re-plotting of this design is not worth the effort. Besides I bought the chemicals and boards already and I dont want to make the final cost be any more than necessary.

Here are some photos showing the old board vs the new. The new one is larger, but that was the best I could do for the circuit with a edge connector and room for trimmer resistors to adjust the circuit sensitivity.

[bkahler]

Wow, lot of expertise involved there!

Hopefully I'm in for two

Brad

[GCinSC2]

WayneG,

Don't own one, but scanned and reviewed the project as a general interest time killer at an airport.

That's a serious piece of reverse engineering and get er done all in one.

Kudos and good luck on the successful outcome.

Reminds me a bit of when I converted a 1985 Caravan 2.2L from carb to fuel inj and had to marry two different engine wiring harnesses a 40 cable replaced by a 60 IIRC. Lots of fun

Gary

[Magnet18]

Wayne, I assume you're talking about OSHpark, I've used them dozens of times, they're perfect production quality boards. Outputting gerbers is pretty easy from any schematic/pwb cad program, and I think there are a couple pdf-gerber converters floating around, feel free to shoot me a PM if you want to email

[WayneG]

I am playing with KiCad now to see how hard it is to make something with it. Hard part is non standard parts require playing with the libraries tor proper board layouts

[WayneG]

Originally Posted by bkahler

Wow, lot of expertise involved there!

Hopefully I'm in for two

Brad

Yes, I will mark you down for 2 when I go through this thread to make the list.

I am getting a little progress with the new circuit board cad program and it has me thinking that I may also do a version II of the module.

If I do it, Version II would include a few more pins to allow the step down light to also indicate that the door is ajar and maybe sound a alarm beeper?

On one journey I had my door not fully closed and it swung open when I went around a curve.
The only problem with this mod is that it will require some extra wiring for some users.
For mine it is easy, I am installing a magnetic reed switch on the new electric steps and that wire was there from the old vacuum steps going to the steps light on the dash, It will ground when the steps are not up.

For the door ajar signal, I will use the original door switch on the new steps, but it will be rewired to go to ground instead of power when the door is closed. I just need to invert that signal in the version II module.

One other warning my rig is missing is "headlights are left on" when the ignition is off, but that may be to much to add?

This is all on the assumption that I can master the software and folks are interested.

[ww4nc]

Wayne,
Count me in for two units
I have an 85 and 86 345 so sure could use them
Dick

[Magnet18]

Wayne, I've tried most of the free cad tools, and KiCAD is hands down the best in my opinion. I have a few hundred hours of experience with it, the big thing is follow some tutorials and generate your parts libraries properly so you only have to do it once
If you want to send me your files before you send them out to fab I'd be more than happy to look them over! I've made dozens of pcbs through OSHpark, could help if you happen to have a quirk they can't handle

[WayneG]

I am still drillin version one boards and testing the first one with a plastic jug with 2 electric contacts in it.
So far, with used antifreeze in the jug, it trips all 3 sensors. I still need to test it with washer fluid, and if I can figure out how, water in fuel?

Before I send any of these out, I still need to mount the module in my rig for a live test. Not a big task in weather above 45F but we are still below freezing.

While I wait I am trying to figure out the new KiCad cad program.
Another steep leaning curve;
Like going from screw top to corked wine bottles, Try and Try Again, I will figure it out

[WayneG]

I am still playing with the PCB design editor, KiCad. I seem to be getting the hang of it and I even have a 3D view of a approximation of the board.

With this design I am including some optional circuits.
1) "Door not closed" and "step not up" will light the STEP indicator and sounds a alarm
2) "Lights left on" with the ignition off will sound a alarm

The "step not up" function uses the old vacuum step connection that had a switch indicating the step position.
With the aftermarket electric steps you will need to add a switch with a contact that closes to ground when the steps are not retracted.
I have installed magnetic reed switch on my new electric steps for this purpose. It will use the original wire to the STEP dash indicator.
I will put something on my web site about this mod when I get a chance.

The door open alarm function needs more work, it will require a wire to run to the module in the dash from the door switch. The contacts need to close to ground when the door is closed. (Electric step style)

The vacuum steps used this switch to power the vacuum solenoid by applying 12VDC from the door switch to the solenoid retracting the steps when the door is closed.
The electric steps use the same switch but requires it to be rewired to a ground signal when the door is closed to retract the steps.

I have found some fancy alarm Sonalerts sounds at this site.
http://www.mallory-sonalert.com/BasicSounds.aspx
They cost more than a simple buzzer, but being it is an Airstream, we dont need no stinkin buzzers
I like this one http://www.mallory-sonalert.com/soun...20SC628CPN.wav

Again, this is a option on the new design, it will raise the price some, but it will improve the functionality of your ride.

If you have any other sound preferences, let me know

[bkahler]

Wayne, adding the extra circuits is a fantastic idea

Thanks!

Brad

[WayneG]

Latest update before I go for more fun and games on Sunday for brain radiation at the hospital in Boston.
I sent my 1st circuit board design off to OshPark, the board maker, and I should get 3 prototype boards by the end of this month. (Not a fast as I would like)
It is not 100% accurate but I wanted to see how well these guys do, it will be a big labor saver not having to make the boards and drill them!

While I wait, I am using a spice program (LTSpice) to test the new and old circuits to be sure they work as they should without being stressed beyond design limits.

Gotta say, I wish I had these tools 30 years ago (about when they made the original modules) Back then, I did all my circuits by hand, no computers!
In the 80's you proved your design on a breadboard by swapping components, your schematics were drawn by mechanical pencils and strait edge. Circuit boards were etched with black PCB tape for the runs and rub on stencils for IC's and component pads.

Times have changed, and I am behind the times. Today the circuit boards would be made four layer with surface mount components.
I like old school circuits that anyone, with some smarts, and access to "radio shack parts" and a soldering iron can repair.

BTW The circuit boards are $22.33 each (without parts) but since I am only charging for the parts & shipping, and not labor for building them, you should still have a better price than any company will charge.
Just hoping the Docs give me enough time to finish them
Wayne

[bkahler]

Wayne, be sure and tell that doctor you've still got things to accomplish in life and you need more time.

Take care and our prayers are with you.

[Keyair]

Super progress Wayne!
Crappy news about what you are going thru tho. Sending well wishes and positive vibes your way!

[WayneG]

Originally Posted by bkahler

Wayne, be sure and tell that doctor you've still got things to accomplish in life and you need more time.

I've been telling them that since it began in Nov. 2015.
It's always "One more appointment"!

Just got to Boston and the only thing on TV is Patriots, for some reason?
I did bring a laptop and programs to work on the module design.