MShift and Toyota A34 Series Info?

[mikeymkll7mgte]

Just a random thought... Could I just send 5v out to the shift lever position switch and put resistors inline with the outputs of the gear positions and tie them all into input 1? And just configure it for variable voltage? That would make my life alot easier right now...

[Bernard Fife]

mikey,

Yes, the variable voltage (aka. "Ford style") lever should for you. There's more here: http://www.msgpio.com/manuals/mshift/V2 ... #voltlever

The VSS example datalog I posted is what you should be aiming for. Speed is a critical factor in the shifting/TCC, etc. so it really needs to be right (you probably wouldn't believe how much effort and experimentation/testing has gone into what appears to be a simple function! I know I wouldn't if I hadn't done it.).

BTW, if you are PWM'ing any output, have you pout a recirculation diode across that solenoid(s)? This really cuts down on noise. There is more here: http://www.msgpio.com/manuals/mshift/recirc.html (it doesn't hurt to put them on even On/Off devices, too).

Lance.

[mikeymkll7mgte]

Well... the "putting resistors inline" doesn't work. Can't get lower than 4.3v. Don't know how im going to get this shifter to work.

I don't have and pwd'd solenoids, and I did not install any diodes either, just what's on the board.

[Bernard Fife]

Mikey,

You need the resistors to go to ground. The signal comes from the non-grounded side of the resistor. The voltage supply needs a resistor in it too, so any pair of resistors forms a voltage divider (Google will turn up lots of examples).

in MShift, the shifter sets the highest gear (plus PNR) and your can MShift to any lower gear using they MShift buttons, some your don't necessarily need allow the manual lever gear positions to be 'sensed' (but P/N, R, and D are required as a minimum).

Lance (mobile).

[Bernard Fife]

For anyone who might find it useful, I have put a quick intro page on setting up the voltage based lever here: http://www.msgpio.com/manuals/mshift/voltlever.html

There is a calculator that can help in setting up the resistor values.

Lance.

[mikeymkll7mgte]

I seen the page you made about 4 hours too late. That would have helped a ton. I got it wired almost the same as your diagram though just thinking about how it would work.

I got the car back together, grounds all changed around for the Mshift (VSS ground to pin 17, the other 3 out to the main bock ground), and twisted the wires for the VSS. I did some testing in the garage and it seemed to be working good. Took it out on the road and it did alright. I will attach a datalog that i took and my current msq. The settings I have in it are what have worked the best so far. Still pretty jumpy and it pegged the speedo out a couple times. Low speed doesnt do very well, but once it gets moving it seems to do ok. I still have the 100k resistor in R59 and the 100k in R45. Input masking is at 40, min speed is 1, reset filter is 1. Changing between rising edge and falling edge doesnt seem to make a difference, and i dont have a scope to be able to see which way is better either. I will be experimenting more tomorrow with different resistors in R59 and R45 to see if i can make it better. Which would be the best to start with? it doesnt seem to want to pick up low speeds very well until the car gets moving more than about 10-15mph. I hope to have this thing nailed down soon. Is anyone else having this much of a noise problem with the VSS or is it just my luck?

[Bernard Fife]

Mikey,

Are you using PWM for line pressure control? If so, it should have a diode across the solenoid, like this:

.

In addition to trying to resistors, one thing you might try is putting a Zener diode in the line from the VSS to Ampseal. The higher the Zener voltage, the more filtering, but also the less of the signal that gets through. The lowest commonly available rating is 2.4 V (such as BZX79-C2V4,143 NXP Semiconductor, 568-5800-1-ND from Digi-Key), and that's what I would try.

Some people do have trouble with the speedo, but it's not consistent, and seems to have more to do with the particular installation than the trans or vehicle.

Lance.

[Bernard Fife]

Actually, thinking about this a little more (and waking up a lot more!), you might try one or two conventional diodes in series with the signal to the VSS pin. The banded end would go towards the controller. Each diode you add in series will cut any signal below 0.7 Volts by that additional amount. So one diode will cut all signal below 0.7 Volts. Two in series will cut all signals below 1.4 Volts, and so on...

If you happen to have an oscilloscope, and could get a trace of the VSS signal, that would be the best way to decide what to do next, of course. We would then know if the signal is high or low amplitude, if it coincided with anything the controller is doing, etc.

Lance.

[mikeymkll7mgte]

The pressure control is cable controlled. I will try the diode inline with the vss tonight and see how it does.

I dont have an oscilloscope, been wanting to get one though. I might see if anyone I know has one I can borrow and see what the signal looks like.

[mikeymkll7mgte]

Didnt get to drive it last night as I was making a much less obnoxious exhaust for the car (neighbors dont like the straight pipe off the downpipe).

I did however put a 120k resistor in R59 and a 82k in R45 and sitting in the shop it seemed very steady. Still doesnt pick up speed below about 12mph though. What should I try to get it to pick up low speeds without being so erratic? I know when i dropped R45 to 47k, it wouldnt pick it up at all below 25-30. How high of a resistor can I go on R59? I was going to try installing a diode tonight after I test drive it.