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TCUs compatible with Phase I 4EAT trannies?

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Hi,

I'm in the midst of trying to narrow down what's going wrong with my Phase I 4EAT. It seems right now the problem is still electrical/electronic in nature so I'm going to do what I can on my end to solve the issue without resorting to expensive mechanical work.

 

Anyway, my questions:

1) What TCUs are compatible with the tranny on my 96 OBW?

2) I want to check to make sure the electrical/electronic system on my car is properly grounded. In particular, I want to insure the electronics on the tranny are properly grounded. How can I check to insure that component is properly grounded?

 

 

Thanks in advance for your help and advice.

 

--Damien

it would be helpful to know if you're experienced with Subaru's such that you've already ruled all the common 4EAT issues. Or describe the issues you're having so we can see if any typical issues are the cause of your problems before chasing weird electrical issues that rarely/if ever cause issue.

 

if it was electrical/grounding in nature i'd want to know if the car has ever been wrecked, flooded, any body work, etc?

 

not that is matters, but i don't think you have a Phase I 4EAT. you have a Phase I EJ25 engine possibly, but the 4EAT was out well before the EJ25 motor.

The Phase-2 4EAT wasn't available until MY 99, so a '96 should have a Phase-1.
WOW, so a 1996 OBW has the same transmission as a 1988 XT6? weirdo. what phase is mine....a negative 1? a zero? maybe they started counting over again with the EJ series? how confusing.
it would be helpful to know if you're experienced with Subaru's such that you've already ruled all the common 4EAT issues. Or describe the issues you're having so we can see if any typical issues are the cause of your problems before chasing weird electrical issues that rarely/if ever cause issue.
I believe it relates to this: http://www.ultimatesubaru.org/forum/showthread.php?t=64167

i think all the information you need is in that thread. it is highly unlikely you have electrical issues. i think you'd be spending lots of time looking for something that isn't there.

 

if you want to thoroughly trouble shoot this thing electrically then your best bet is probably to go through the trouble shootin schematics of the FSM. they are quite thorough and detail everything. i think those are available online but i don't know where.

WOW, so a 1996 OBW has the same transmission as a 1988 XT6? weirdo. what phase is mine....a negative 1? a zero? maybe they started counting over again with the EJ series? how confusing.
It seems that significant differences triggered the "Phase-2" label. The last page of the following has some pics for IDing:

http://www.endwrench.com/pdf/drivetrain/02Winter4EATTransOp.pdf

  • Author

I've spent enough time troubleshooting the problems with my 4EAT to be reasonably certain that electrical/electronic problems may very well be the matter. I'm going to go that route first before I consider an expensive shop repair.

 

Can anyone tell me where the TCU is actually located? I know it's under the steering wheel somewhere...a picture or two of what it actually looks like would be helpful.

 

Thanks!

 

--Damien

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