Chrysler 41te Trans Control

[cododgeneon]

Thanks Lance and Thad.

I would love to test it out. Last I heard is we need it to shift 4 soleniods instead of just 2.

My car is about 60% completed right now, as soon as I get my tubular manifold made ill be ready to rock and roll on the testing, 41te is already built, convertor is ready to be put in. Just waiting for the manifolds.

Thad if you dont get steve (im sure he would do it thou) let me know

[Bernard Fife]

Last I heard is we need it to shift 4 solenoids instead of just 2.

cododgeneon,

The current code has 3 user configurable outputs for shift solenoids (used for the SolA, SolB, and the 3/2Sol on the 4L60E). There is also a line pressure control solenoid output (user configurable) and a lock-up torque converter clutch solenoid (user configurable). In addition, there are two spare outputs that can be set by a user-specified combination of vehicle speed, engine rpm, load, or current gear (with user-set hysteresis to prevent rapidly cycling near the switch points). These can alternatively be used as 'clutch outputs' (i.e., active only during a specific shift).

So the question becomes, "is some combination of these seven outputs enough for the 41te, or do we need more (or possibly to add some flexibility to the spare outputs)?"

Someone is going to have to do the digging and figure that out. I will help as much as I can, but if anyone has a factory service manual for this transmission, it would probably answer most of the questions we would have (though likely implicitly!).

Lance.

[tjabo]

Thanks guys!

Lance, I have a factory service manual for my wife's minivan that has this trans in it, so I'll dig into it some this weekend. I'll also paste your post into an e-mail to Steve (Lockett), since I'm pretty sure he can answer that off the top of his head. He's like a Chrysler ATx savant!

Thad

[cododgeneon]

Thad, ive already contacted steve about this, he said he will test it for us.
He's going to read this post later tonight when he gets home

[tjabo]

Awesome! ! ! !

[Bernard Fife]

Guys,

Once we have the control strategy nailed down (how many inputs/outputs and how they are used) the next step would be to verify the electrical characteristics of the transmission components, and see how they line up with the capabilities of the GPIO board.

This includes things like the shifter outputs (digital or voltage based or ...), the solenoid resistances (and PWM frequencies where applicable), and the trans temperature sensor output curve (if it has a temp. sensor). Some of this will be in the service manual, some might require more digging. It's all very helpful, though, and knowing it 'up-front' will make the beta testing much easier.

So if anyone has reliable info they can add on any of this, that would be great!

Lance.

[racerstev]

Guys,

Once we have the control strategy nailed down (how many inputs/outputs and how they are used) the next step would be to verify the electrical characteristics of the transmission components, and see how they line up with the capabilities of the GPIO board.

This includes things like the shifter outputs (digital or voltage based or ...), the solenoid resistances (and PWM frequencies where applicable), and the trans temperature sensor output curve (if it has a temp. sensor). Some of this will be in the service manual, some might require more digging. It's all very helpful, though, and knowing it 'up-front' will make the beta testing much easier.

So if anyone has reliable info they can add on any of this, that would be great!

Lance.

I have most of this, I'll do some digging around for as much as I can find.

Are there any loggable pressure inputs? This trans has 6 pressure ports that have been a huge help setting up shift blending.

We also have 2 speed sensors, one on the output and one on the turbine, very handy to see if the clutch packs are slipping and
to check converter-lockup slippage.

Steve Lockett

[Bernard Fife]

racerstev,

There is one dedicated line pressure input, and more free ADC (voltage measuring) inputs that could be used simultaneously for more pressure sensors, depending on things like the shift lever signal (for example, if the shift lever is voltage based rather than digital, there are two more ADC voltage channels available in the current code). There is also an ADC channel freed up if using CAN (w/ MS-II) to get the load (MAP or TPS).

The default line pressure sensor is for digikey MSP6907-ND for $114. It's a 0.5-4.5 Volt output (accuracy ±5 psi), and has just a three wire hookup (5V, ground, and signal). It has a 1/8" NPT thread.

The input shaft speed sensor is also used on the 4L80E transmission from GM, among others. We plan to support its use, but this isn't in the code at the moment. Once implemented it could be used for the 41te trans as well. The input shaft speed variable is in the code, but it is currently calculated from the output shaft speed and gear ratios (and assumes no slippage in the gears), it allows the code to derive the converter slippage. Of course measuring the input shaft speed directly is better for the reasons you mention, and this should be straightforward.

Lance.

[tjabo]

I ordered the parts from Digikey, and I'm doing some reading of the build threads on the site and the assembly manual between now and when everything arrives so I can get crackin' on the build in a time frame that works for Steve's testing.

Lance, I don't know what kind of sensors Steve has been using for his datalogging, but assuming he still has them, might we be able to make some provisions for his to use them with this Mshift?

Thad

[cododgeneon]

Thanks Lance for helping with this.


Also thanks Thad for tackling this project, like steve said he will test it in Febuary which is only a couple weeks away.