Auto a340e trans + Link G4+ + OEM ECU - which signals does the auto box need?

Hi guys,

Apologies if in wrong thread, I love to think my whale is a 4-door supra, but if the question is in wrong place, please move it / let me know.

I`m running a wire-in G4+ Xtreme Link ECU in an mk2 Aristo (1997, 2JZ-GTE VVTi, a340e auto box), with OEM ECU controlling the auto box. (HKS T04z kit, auto trans, LINK G4+ Xtreme ECU). Car is wired, mapped, everything works as it should as far as engine goes, but the box doesn't shift as it should. At the moment, there`s no manual mode (M just flashes, doesn't react to shift button on the wheel if I select manual mode) and the box upshifts at ¬2500 RPM no matter what, kick-down not present at all either.

Obviously, I can keep it in locked 1st or second using the shift lever, but that's about it.

All the engine signals are wired into the LINK ECU, what we don't know / can't figure out is what exact signals does the auto box / OEM ecu need for it to work? Is there anybody that can share some wisdom, please? Any help would be appreciated, I'm seriously looking forward to enjoying my car to it's fullest ASAP.

Any question / additional info needed please let me know and I`ll try to reply as accurate as possible.

Thank you all,

Vali

Assuming as you mention Aristo you are using the later tiptronc box with the buttons/paddles on the steering wheel?

Assuming as you mention Aristo you are using the later tiptronc box with the buttons/paddles on the steering wheel?

yes sir, that's correct

Did manual mode work before the Link ECU was added?

Did manual mode work before the Link ECU was added?

Yes of course, perfectly. Had the car for 2 years on stock ecu ECT/PWR or snow mode all worked fine, never had problem with shifting, or any kind of issue for that matter.

You should have left the stock ECU to control the gearbox, and the Link to control the engine functions

Assuming this 'fault' is self inflicted and not a failing old OE ECU, there are 12 wires between the transmission and ECU, you will find your Gremlin amongst them somewhere?

Check all these connections are sound, especially the two speed sensors, instead of being split between the 2 ECU's one of these may have been routed to the Link only?

You should have left the stock ECU to control the gearbox, and the Link to control the engine functions

That`s what we`re doing Swampy, there just must be something that we`re doing wrong

That`s what we`re doing Swampy, there just must be something that we`re doing wrong

Invisible ink strikes again?

Invisible ink strikes again?

Sorry David, not sure what you mean?

Assuming this 'fault' is self inflicted and not a failing old OE ECU, there are 12 wires between the transmission and ECU, you will find your Gremlin amongst them somewhere?

 

Check all these connections are sound, especially the two speed sensors, instead of being split between the 2 ECU's one of these may have been routed to the Link only?

?

?

Thanks David, but my question is: Do you or does anybody else know what the 12 wires are exactly? Which are the signals needed for the ECU?

You'll need a VVT-i wiring diagram for that which I don't have, but you are making a bigger job of it than it is.

It has 12 wires because it needs 12 wires and they are all colour coded, simply join up the dots.

The search button works a lot faster than mere squawking too.

Thank you!

For ease of reference, I have added the pin-out pic to the VVT-i information page in the Transmission Group.

http://www.mkivsupra.net/vbb/group.php?discussionid=250&do=discuss

One fine day after you have coughed up your subs, you will be able to access this remarkably useful Club resource.