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AW-4 Shift Controller and LED Gear Indicator Mod

AA vs AB is almost always just a minor, but compatible, firmware or design update. I can only think of two examples that aren't compatible or are entirely different parts, and neither is really relevant here.

Engine braking in 1-2 is due to (iirc, I haven't checked the AW4 section of my FSM in a while) the hydro circuit for the overrunning sprags being enabled with the gear shift in that position only. I looked into ways to enable it at will in 3/OD and couldn't find anything easy (i.e. did not require valvebody mods) - perhaps Fringe XVO could do something about that? I'm an EE not an ME, looking at the hydraulic flow diagrams tends to throw me for a loop.
 
kastein said:
AA vs AB is almost always just a minor, but compatible, firmware or design update. I can only think of two examples that aren't compatible or are entirely different parts, and neither is really relevant here.

Engine braking in 1-2 is due to (iirc, I haven't checked the AW4 section of my FSM in a while) the hydro circuit for the overrunning sprags being enabled with the gear shift in that position only. I looked into ways to enable it at will in 3/OD and couldn't find anything easy (i.e. did not require valvebody mods) - perhaps Fringe XVO could do something about that? I'm an EE not an ME, looking at the hydraulic flow diagrams tends to throw me for a loop.
Click to expand...
Yeah.. I already have a Transgo shift kit in the trans (probably irrelevant), but what I'm not sure about is whether or not the shift solenoids control the gear selection in the 1-2 position... My theory is that I'll be able to control the gear selection in 1-2 with my modded RAD shifter (so, theoretically be able to shift into 3rd gear) while having the OEM shift lever in the 1-2 position which would enable the engine braking in those 3 gears...

Iirc, 1-2 has an output on the NSS.. Gotta dig up my FSM when I get home tomorrow.. ;) Who knows. Maybe it's engages engine braking electronically through the NSS. :dunno:
 
No, you won't be able to. The mechanical shifter overrides the electronic shifter - I tested that sometime in '10 on my 98 and if it's in 1-2, you can only select 1st or 2nd electronically. Unless the transgo kit changes that.
 
kastein said:
No, you won't be able to. The mechanical shifter overrides the electronic shifter - I tested that sometime in '10 on my 98 and if it's in 1-2, you can only select 1st or 2nd electronically. Unless the transgo kit changes that.
Click to expand...

Same in D you only can shift 1,2,3 and only have compression braking in 2,3. In OD you get all 4 gears but only 3,4 compression braking. This was as tested in my '93 XJ. Best way to overcome this is to incorporate electrical in the floor shifter.
Like this :D http://www.naxja.org/forum/showthread.php?t=1096300
The TC should lock in 3rd or 4th, as I remember it does.
 
R.DesJardin said:
Same in D you only can shift 1,2,3 and only have compression braking in 2,3. In OD you get all 4 gears but only 3,4 compression braking. This was as tested in my '93 XJ. Best way to overcome this is to incorporate electrical in the floor shifter.
Like this :D http://www.naxja.org/forum/showthread.php?t=1096300
The TC should lock in 3rd or 4th, as I remember it does.
Click to expand...
Hmmm.... Interesting. So all it's doing is engaging the torque converter? I might have to dig out my arduino and start playing with it..(to keep the tc from being engaged below a certain RPM in 1st @ low speed) And that shifter is making me :drool: :D
Talyn said:
Where does one obtain one of these modded controllers?
Click to expand...
Nowhere yet.. Just playing with the idea at the moment. Unless you want my prototype.. LMAO. :D
 
bpas328xi said:
Hmmm.... Interesting. So all it's doing is engaging the torque converter? I might have to dig out my arduino and start playing with it..(to keep the tc from being engaged below a certain RPM in 1st @ low speed) And that shifter is making me :drool: :D

Nowhere yet.. Just playing with the idea at the moment. Unless you want my prototype.. LMAO. :D
Click to expand...

The TC only locks in 3rd or 4th, this is the factory design. There is several sensors that input into the logic for TC lock, includes TPS, VSS, RPM some had H2O temp input so it won't lock up when cold. As TC lock seems to work, it unlocks when: you gas it, let off the gas, hit the brakes....
 
R.DesJardin said:
The TC only locks in 3rd or 4th, this is the factory design. There is several sensors that input into the logic for TC lock, includes TPS, VSS, RPM some had H2O temp input so it won't lock up when cold. As TC lock seems to work, it unlocks when: you gas it, let off the gas, hit the brakes....
Click to expand...
But it also locks in the 1-2 position on decel right? Sounds easy enough to duplicate with an arduino... :dunno: :D
 
No. overrunning sprag vs torque converter lockup is very different - if you lock the TQ in 1/2 you will only make it stutter and wear the lockup faster, it's not designed to handle low end torque or being stopped when it's engaged. If it's in good shape it'll stall the engine on you.

I'd have to check the hydro diagrams again but I don't think 3rd has engine braking, either...

edit: Talyn, I can post up a wiring diagram for the setup I put together for lobsterdmb if you want, it basically has full auto, full manual w/ input from the RADesigns shifter, and a torque lockup that I set up to only work when the brake lights are off, it'd be trivial to make it also only work in 3/OD to avoid lurching+tq damage. Fairly simple to add a gear indicator if you wanted to, I would use a 74LS148 priority encoder or diode logic plus some buffer/drivers, a 74LS47 or 74LS48, and a seven segment display... or a PIC/AVR microcontroller, or a basic PLD or PAL/GAL series programmable logic chip if that's how you swing. Rather than indicating 5 for OD+TQlock, my suggestion would be to use one of the decimal points as the lock indicator.

I should note - I am not selling this. Wiring diagram is free, build it yourself, use it with whatever manual shifter you want to buy or build.
 
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Another option for control is to use the Range selector switch(NSS) it can be wired to give you manual control electrically when you move the floor shifter. I know of a guy who has done this. Not sure what years of NSS this is able to work with.
It would seem that Kastein, myself and you should be working instead of playing on the internet............... Actually, I took this morning off to be on Grandpa duty.
 
My home brew manual switch control is set up the following way:

* A toggle switch to select between normal and manual mode

* A 6 position rotary switch active in manual mode with the following selections :

Pos 1 = 1st gear
Pos 2 = 2nd gear
Pos 3 = 3rd gear
Pos 4 = 3 gear w/ TC lock
Pos 5 = OD
Pos 6 = OD w/ TC lock

I also have another toggle / rocker switch to lock the TC in 2nd gear only.

The rotary and rocker switch are mounted in the hump cover rear of the transfer case shift lever and left of the console.
It's a natural place for me to rest my hand.
The auto / manual toggle is hidden under the dash.

Works great and gives all the gear selections possible and ends the "hunting" too.
 
bpas328xi said:
As for tiptronic... I might look into doing that for my XJ once I figure out how I would ideally like to do it since I have a Grand Cherokee steering wheel that has stereo control buttons on the back that I could probably remove to make room for paddle shifters.
Click to expand...
That is what I was thinking. You have those two useless buttons on the back side of the wheel.
 
R.DesJardin said:
Another option for control is to use the Range selector switch(NSS) it can be wired to give you manual control electrically when you move the floor shifter. I know of a guy who has done this. Not sure what years of NSS this is able to work with.
It would seem that Kastein, myself and you should be working instead of playing on the internet............... Actually, I took this morning off to be on Grandpa duty.
Click to expand...
Haha. My excuse is that I'm in college. LMAO. Driving home in a bit to wrench on the XJ. :worship:
Talyn said:
That is what I was thinking. You have those two useless buttons on the back side of the wheel.
Click to expand...
Yes. And I also have two extra wires on the clockspring (swapped in the GC clockspring too)... So.. I could do paddle shifters for me. :D
 
Finished working on this controller today. After some minor wiring issues, all is working great.
No CEL's, no extra switches used or needed to turn on-off. No manual TC control.
Made a 'patch cable' to tap and intercept and wires needed on one and went right into the TCU and made all the wiring connections needed on another one.

Have 2 versions.

1-uses the RAD shifter where in 4th gear position, the trans works just as normal. Move the shifter to 1st, 2nd or 3rd position and it holds the trans in that gear and shifts as you move the RAD shift lever. No separate TC lockup switch- lets the TCU control TC lockup as usual. LED reads what gear you are in 1-4 and 5 when TC is locked. LED display only comes on when stock shift selector is in D/OD, 3, or 1-2. LED goes blank when in P, N, R.

2-uses the switches and LED in the vent area. Works exactally the same.

Pics and video to come.
 
CobraMarty said:
Finished working on this controller today. After some minor wiring issues, all is working great.
No CEL's, no extra switches used or needed to turn on-off. No manual TC control.
Made a 'patch cable' to tap and intercept and wires needed on one and went right into the TCU and made all the wiring connections needed on another one.

Have 2 versions.

1-uses the RAD shifter where in 4th gear position, the trans works just as normal. Move the shifter to 1st, 2nd or 3rd position and it holds the trans in that gear and shifts as you move the RAD shift lever. No separate TC lockup switch- lets the TCU control TC lockup as usual. LED reads what gear you are in 1-4 and 5 when TC is locked. LED display only comes on when stock shift selector is in D/OD, 3, or 1-2. LED goes blank when in P, N, R.

2-uses the switches and LED in the vent area. Works exactally the same.

Pics and video to come.
Click to expand...
So... When are you going to start selling the first one? :)
 
Came up with version 3. It was eluded to above by Rory and I thought about it more.

Using the stock shifter lever and one switch labeled 'manual-auto', and the controller is wired inside the TCU box with just 1 wire coming out going to the 'manual-auto' switch. The 'manual-auto' switch (it looks similar to the switches in the vent pod just labeled different) can be mounted on the flat just to the right of the shifter.

In this V3, switch in 'auto' and everything works as stock. When switch in 'manual' moving the gear lever selects the gear. 1-2 position is 1st, 3 position is 2nd, OD position is 3rd gear, with the lever in OD position move switch to 'auto' and goes back to stock. I had a label/bezel/plaque made that goes right next to the stock lever indicators, in vertical letters, 'MANUAL 3 2 1'. It's not 'speedshifting' with the stock shift lever.

Now engine braking will occur as the shift lever will be in 1-2 position and trans locked in 1st gear only and will not shift into 2nd.

This is as simple as I can make it. No LED for gear indicator, no external shifting device or switches like the RAD shifter or those vent mounted switches, just 1 switch to turn 'ON-Manual' 'OFF-Auto'.

No CEL's and yes it uses the NSS switch for input.
More to follow with pictures.
 
Nice work on the controllers. I have a few questions about basic AW4 control. Do the shift solenoids run on full 12VDC? How many amps? Are you guys using relays and microswitches , or just microswitches for solenoid control?
I am running a '96 XJ- AW-4 body with a 3.0L Non turbo Mercedes diesel. I just started road testing a few days ago, and I am having shifter issues. I am on the fence about making a stand alone trans controller, because at present I have partial success operating in "D", and I would prefer if possible to have a option for fully automatic shifting.
At present, I have the old jeep Throttle body hooked up to its 3 sensors, and the throttle body is just hanging not hooked up to anything else. The jeep throttle cable is hooked up to the MB injector pump and that works well. I have not hooked up the cable that goes to the trans ( NSS?),. So the TPS is hooked up but not moving, the trans cable/NSS is doing nothing.
When the trans is not connected to the TCU, I get manual shifting I think position 1-2 = 1st gear, position 3=3rd, and D=4th with no lockup. When I hook up the trans to the TCU, I only get 1st gear in any position, when I flip the switch for the E-fan (manually jumpered on the bottom of the electric distribution box on the bottom of the E-fan relay, then the trans will shift in D, and I get 1,2,3,4. I have not gone fast enough to see if I get a TC lock up ( death wobble), and the shift points are not at the best speeds. All this is happening and I lost my speedo indication somewhere along the way.
I am hoping to get the trans cable/NSS hooked up but as it moves opposite the throttle, I will have to make a long bracket that will work opposite the throttle. The Throttle position sensor has more travel/rotation than the MB injector pump by quite a few degrees of rotation, so if I want that to work I will have to make some sort of bell crank travel extension for it, which is going to be a PIA, I can do it but it will be a pain.
So far my best success has been with the trans hooked up to the TCU, but I lost the speedo. A manual controller might be nice as the little benz needs to hold on to 2nd and 3rd longer than it currently is, OR that problem may fix itself if I get the TPS and the NSS working as intended. I still need to figure out the speedo.
Any thoughts on why I lost the speedo. all the sensors are hooked up except one O2 sensor in the exhaust.

Any help would be appreciated
 
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