rusefi.com

Pretty simple automatic transmission - two shift solenoids and torque converter clutch solenoid, "line pressure is by mechanical cable" whatever it means.

Diagram
http://rusefi.com/wiki/index.php?title=Vehicle:Mazda_Miata_2001#Automatic_Transmission

https://github.com/rusefi/rusefi/wiki/HOWTO-TCU-A42DE-on-Proteus

I've got couple of units as connector donors and just got a pigtail today. First step would be making a harness extension so that I can analyze stock TCU behavior.

Looks like a 35 position connector? Will try getting part number from TE support people on Monday.

High-side solenoid control and VR speed sensors? Will measure solenoid resistance soon.

I've destroyed the connector pictured above while trying to solder wires to it Looks like a PCB is pretty much required, next step is measuring the pinout. TE Live Product Chat were not able to identify this part.

did you mean controlling auto trans via rusefi?

mattsabun wrote:did you mean controlling auto trans via rusefi?

Yes

great!!
i got kia carens with auto transmission very similar with lantis gearbox.
faulty maybe from ecu or wiring harness, I am not check it yet.

Finally I've decided to open my eyes and realize that it's a JAE connector. Wire side is MX7-A-35SC http://jae-connector.com/en/pdf/SJ028726.pdf

For board side we can use left part of attached larger header, I was not able to find a 35 header so far.

Actually page 4 of attached has the 35 header.

[video]https://www.youtube.com/watch?v=C-vD95qKoMo[/video]

Solenoids diagram added to http://rusefi.com/wiki/index.php?title=Vehicle:Mazda_Miata_2001#Gear_diagram

All three solenoids are 18 Ohm each. Looking at the diagram these seem to be high-side controlled? Could it be simple on/off? Should I solder a couple of toggle switches and try to drive it like that?!

[video]https://www.youtube.com/watch?v=rYto781SRiw[/video]

russian wrote:[...]All three solenoids are 18 Ohm each. Looking at the diagram these seem to be high-side controlled? Could it be simple on/off? Should I solder a couple of toggle switches and try to drive it like that?![...]

AFAIK the solenoids A/B are definitely just on/off. So is -presumably- TCC.

There could be a lot of overlap with this unit

Several years ago i was working with AW4/A340 transmissions for drag racing applications meaning that are only for manual paddle operation,
is basically a driver board with a 7 segment display for gear indication and a simple Arduino logic arrangement. Today im converting a Lexus with a 1JZ GTE VVTI to rusefi and im planing to use this board for shifting the transmission and controlling the trans pressure solenoid from a PWM output from the rusefi. If you are interested i can send you one so you dont have to use that crazy switch board.

YES! Just emailed you my address.

It's rudimentary but works,

Wiring is documented at https://github.com/rusefi/rusefi/wiki/HOWTO-TCU-A42DE-on-Proteus

Interesting project! My buddy got this 2003 Miata project we'll work on right after we finished installing the suspension from 4Wheelonline onto the trucks and clear the garage. I'll let him check he likes the transmission controller idea of yours.

Status update:

turbine shaft input seems to work, output shaft so far no good reading. turbine shaft is sometimes RPM sometimes output with gear ratio:

(a bit off Matt)

turbine INPUT is fixed ratio to the output when IN GEAR ONLY
in neutral it will be almost engine speed
it's on the output of the torque converter

aka locked to engine only when lockup clutch is closed

when in gear, it should exactly match transmission gear ratio for ISS / OSS
when TC locked, ISS = engine RPM
the TC has a clutch that turns it in to a fixed coupler instead of a slippy hydraulic thing
older boxes didn't have the clutch at all
it started showing up in the 90s

https://rusefi.com/online/view.php?msq=975
https://rusefi.com/online/view.php?log=768

good news zero ISS one I've turned off engine
bad news noisy value while ECU was idling

filter parameter 5 and 10 still too much variation in output

https://rusefi.com/online/view.php?log=770
https://rusefi.com/online/view.php?log=771

start, idle, stop

99 at 4 https://rusefi.com/online/view.php?log=772

16 at 8 https://rusefi.com/online/view.php?log=773

Some fresh data towards input shaft speed filtering