TrollHammer

I'm looking at replacing my TCU/shifting arangment to allow for more control over the transmission. I've been looking at some of the other threads and am applying what I know about controllers.

What I'm wondering is how much interest would others have in a DIY replacement kit composed of parts available inexpensively? If others are interested, I'll focus on trying to make my project something repeatable (as in, not cutting into wiring harnesses and whatnot).

So far, what it would look like is a touch screen controller that would install in the dash about where the current clock is on 95 and older jeeps (none of my jeeps had a clock there, I found them in the junk yard. it looks like there are places for other idiot lights, but I'm not sure what they were. Anyone want to enlighten me?), and a foot switch for TC lockup on the floor about where the clutch would be on a manual trans.

The screen would be menued allowing for normal Automatic operation, Semi-Automatic operation (up/down selection of gears), and Manual (a button for each gear, so you can switch to whatever gear you want, as well as a TC lock button and Neutral if I can make it work.

There would be a menu for feature settings, in cause you don't want a footswitch or want to add your own switches, and these would be able to be set for whatever behavior you want. This way, if you'd rather have the foot switch toggle between TC lock and Neutral, or TC lock and unlock, or TC Unlock and Neutral, you have the ability to change it without connecting a computer or knowing programming (as would the whole thing.)

I would be providing a parts list and the program code. Due to the possiblity of damage and whatnot, You'd have to put it together yourself, but I'll try to make it as easy as possible.

Number one rule is that it should be fairly cheap and easy. So far, I have sourced the main parts at about $80 plus shipping, all from Amazon and MPJA.com. I just need to find a TCU connector and the clock connector (though these are different in different years. The project will target 91-95 model jeeps, as that is what I have).

Interest? Comments? Features desired? "Please not another one"?

BNJeepsta

I dig it, but sadly, I have a 97... On a different note, what will you be using to control the TCU? Something like a PLC?

TrollHammer

I haven't nailed down the exact model, but I'd be using an Arduino controller. They cost around $20-25, and the standard allows for stacking option modules called "shields". A relay card is about $25 and the 3.2" touch screen is about $20. The foot switch is around $10 or less, if I remember. I still need to figure out how many relays are needed of what kind to know which board is needed, or If I have to remote it off-shield.

I've worked with PLCs and microcontrollers, and the Arduino is the best bang for the buck for features in my experience. PLCs are good, but more expensive and don't always have the speed or flexiblity (like analog inputs).

I have just found a color screen in the same format, but it's around $50. I'm not sure what it would add to the project, though, other than "looks cool" and maybe a backlight. Bit outside the project, but when I get the code done if someone else wanted to mess around with it I'm sure you could make it do a lot more.

As to 97+, if someone wants to dig up what's different connection-wise between the two TCUs and figure out a spot to put it, it should be easy to modify the plans.

BNJeepsta

I work with PLC's a lot at work, but mostly just wiring. I understand the programming, but I'm not well versed in it.
As far as the fancy display goes, I don't see a need for it, but backlit is a must have. Gotta be able to see it at night when its dark in the cab!

I'm 100% on board with this, so any info you want on the 97+ just pm me and ill get it for you. I have access to a 97, 99, and 01. I would probably mount my screen next to my shifter or on top of my dash. Like I said, any info you need, pm me and ill get it for ya

TrollHammer

The screen is just convienient, it allows for multiple sets of buttons in whatever configuration is needed for 20 bucks. I can get switches for a little cheaper, but then would have to wire it up, not that that is too big a deal. I just figured it is plug in hardware thst fits in the dash blank in my jeep. Switches or buttons are definately easy to implement. Plenty of digital inputs (if Im looking at it right, most of the screens are more compatible with the Arduino Mega over the Uno, and it has like 54 inputs/outputs. Overkill.)

Programming language is C, which I've been working extensively the last year at work. My previous project had been in RLL, using an automation direct PLC (nice controller, and WAY cheaper than most: a DL06 is just over $100.)

Anyway, if switches/buttons are more ideal it would just be the arduino (20) and relay board (25), plus the switches and maybe some sort of power supply.

What would be more ideal, and from a user standpoint, what switch layout would be good? Easiest I can imagine would be one switch for TC lock and one two way momentary for up and down through the gears, and a third to switch between auto and manual. Another would be a button for each gear... Hmm...

As far as what I need to see from different years is the connector and pinout, I think.

BNJeepsta

I think switches and buttons would be nice, but there would be a crap ton of them and that could be a pain. The screen would simplify everything and put it all in one spot. If you could keep it to 3 switches (tc lock, momentary for the gear selection, and one for manual/auto) that wouldn't be bad. Ill try to get some pics and info on the different connectors and pins for the newer TCU's soon.

TrollHammer

Rough idea what the parts might look like:

The screen:



A relay board (might need more relays than this, don't know yet):



The controller:



There might also need to be an adaptor between the controller and the screen (or an extention, as the relay board doesn't have the pass through on the end for the display), there are several "packages" that have the controller, screen, and adaptor board in one shot for a few bucks cheaper.

I just need to source a decent power supply (probably a USB car charger. I'm guessing around 5V @ 2A and a bit more rugged than the average charger), the connectors, and a housing, preferably one that is shielded (though one could use aluminum tape for that)

Found out today our household income is getting reduced, which will mean this will be slower development, but at least the time consuming part (the programming) doesn't cost anything!

(and no, I don't know why the links are screwed up and doubled up. Tried to fix them but seem to be goofing them up more.)

BNJeepsta

I love it! As far as power supply goes, where would the initial connection be? Would you simply plug it into the 12v outlet in the dash or tap into the fuse block?

I think finding a shielded housing would be a cleaner look, but depending on cost, it may be more economic to go with the old aluminum tape lol

With the packages that include everything, are they the same quality and do they have the same features that you can get with piecing everything together? If they are a good quality and have the same adjustability, I'd say go for it.

TrollHammer

In theory, the parts are a set standard, using all the same basic ICs and whatnot, and they are all roughly the same price overall. The "true adruino" boards are considersd to be from companies that send a portion of the proceeds back into the Arduino community, as it is an open source project on a world wide scale. In all technicality, all the blueprints for the boards, IC parts lists, and everything else is provided free of charge online, the various companies (Sainsmart, Seeed, Sparkfun, Osepp and half a dozen others) just build the boards so you dont have to. Its really economical.

That said, the companies themselves do have some degree of quality control standards and whatnot. For example, Sparkfun pays back to the community, make a quality product, have some warentees, and cost about 10-20% more, whereas Osepp is a shade cheaper, has a decent product, less features, and does not pay back into the community. As far as reliability and quality, it will kind of be up to the individual as to which make of board they want to use.

As far as the grouped parts vs individual, I need to do more research, but I believe they are all SainSmart, and Im not sure but I think they are chinese. Radio Shack carries most of the same parts from Seeed (I think), but charge almost double (but you can see the parts you are buying. No guessing as to if they were machine or hand assembled).

As to power: Im hoping to pull power from the TCU connector and the Clock connector. Clock has both full-time live power (to maintain the clock) and On/ACC power (to light the display), but these are pretty low power lines. The TCU has to be powered though, with plenty of power to both run the TCU and turn on the solenoids, so this should have plenty of juice.

It may not even be an issue for the standby power, if the clock is not needed, but Id hate to have someone (like me) feel that they have to give up their clock to gain control over their transmission, so it wouldnt be too hard to add a date and time clock to the display, but the controller would have to be powered to do so ( unless I can find a realtime module for it) and I fear that the timekeeping might not be up to par when the controller is in low power mode (about 1ma).

I did note that the parts listed are on sale, I might just go ahead and order some anyway...

BNJeepsta

The 97+ do not have a clock, so power would have to come from somwhere else correct?

TrollHammer

Main power would/could still come from the TCU connector, it would have power too. Flock power just would have "memory power" if the unit needed to have power full time. The controller I have been messing with has a HUGE file loaded on it (80% of its capacity) and takes about three to four seconds to boot up. If I learn to write bootstraps (the part that tells the controller how to read the file), this time could become much faster (by cutting out all the stuff that isnt needed). If its an issue we can probably grab full time power from somewhere or add a "good to go" light. Im not too concerned about it.

Im more concerned about sequencing of the gears in auto. The main reason I want to do this as a replacement instead of the usual bypass is because I dont like the odd inbetween shift between second and overdrive (feels like third has a different ratio than when it shifts between second and overdrive, and only stays on this inbetween for a moment), and I also dont like how it will lock into overdrive/TC lock when easing into an uphill. The controller should be able to read any signals the transmission puts out, I need to do more research into how mich is electronically controlled and how much is mechanically (kickdown cable might be adjusting a fluid valve, not an electronic sensor).

How do you like the way your 97+ shifts?

CobraMarty

The 'kick down cable' is not a kick down but is a line pressure increase cable.

TrollHammer

Thats kind of what I'm getting at, and thanks for the input, (do you have any more info/clarifciation?). There's some mechanical element to the shift points that the TCU has to work with, just need to figure out if the "funny shifting" that a few complain about is because of the mechanical part or the electronic part. I can play with the electronic end, but other than indexing that cable, there's not much I can do with the transmission itself.

Well, I guess it's good to shop around. Amazon and Ebay have the set of boards for $49 and 50 this morning, give or take shipping, which I felt a little bad about since amazon was 45 shipped last night. I wanted to verify what I was getting into and went to the sainsmart website and, wonder of wonders, they have it on sale for $41 shipped!

http://www.sainsmart.com/sainsmart-m...atmega8u2.html

Here's the kicker: it's actually a backlit color touchscreen, which I figure is ideal. Not that color is needed, but it can help with gear indication better than if it was just black and white.

Hopefully today I'll get one ordered and be able to track down the other threads I read before about TCU/transmission functions. It's all here somewhere.

TrollHammer

Ive been going through the AW4 tech manual and Im scratching my head. So far the thing I can figure out that might "shift funny" is the torque converter lockup. It seems to not be regular through the gear selections. Some get TC lock, some dont. Otherwise there isnt any odd order to how it shifts, or inbetween gears, just first through fourth and the TC.

I did learn something interesting: if you unplug the TCU, and just run the trans without it, it shifts like this:

Park through neutral=normal
D (fourth)= Overdrive only
3= third gear only
1-2= first gear only

and as far as I can tell, no TC lockup. If someone wanted quick, crude manual control over the trans, they could pop it out and hook a switch between the TC wire and power (12v) you would lose second, but for cheap and dirty, there you go.

Anyway, started laying out the program. The menuing is going to be (for me) almost as much trouble as just hooking up banks of switches. That said, since there will be PLENTY of extra IO, Ill leave allowance for both pushbutton shift selection and rocker switches, rotary, or what have you, and the foot pedal(s). Kind of an all-in-one unit. One pedal option is a rocker pedal for gear select and one pedal for TC, if one should feel like doing it that way (I probably will, which is why Im going to the trouble).

On the other side of things, I have a feeling that the unit will need to be in two boxes: one for the screen and one for the relays and connections. Jist too many boards without making something custom. (LCD+Adaptor+Relay+IO+controller, and each about 1/4 to 1/2" thick... I dont think there is room). but I guess this way if someone doesnt want the display I can plan it so you just dont plug that box in (ie: dont buy the parts).

The screen, though, will be user configurable. Just draw up a menu in Paint as a bitmap, use notepad to write a file that tells where the buttons are and what they do, save it to an SD card and pop it in. Get tired of how it looks or want to change it around, pop out the card and change it yourself. No programming knowledge needed.

At least thats the plan.

CobraMarty

Downshifting is also interesting.
When slowing down like coming to a stop,
the sequence is 4th then 2nd for a second then 3rd then 2nd then 1st.
Weird that is engages 2nd before downshifting into 3rd.