L series auto to manual conversion

T'subaru · Post by **T'subaru** » Sat Nov 21, 2009 10:32 pm

I'm planning on swapping the engine and all drive train from my '89 rx to a 89 wagon. Both are awd ea82T. The wagon has an automatic trans, the rx 5 sp. The mechanical is no problem but the wiring is my concern. I have to swap instrument clusters and Im wondering how much of the wiring underdash has to be addresses. I dont think much has to be altered underhood either, but this is an area I have little knowledge or confidence in my abilities. Any guidance would be greatly appreciated.
Cheers, Mark

steptoe · Post by **steptoe** » Sun Nov 22, 2009 11:46 am

there is something in the ECU 3 plug diagram, so not yours, with regards to manual or auto, simply earthed or not earthed on one pin. Maybe check this with 4 plug ECU pin diagram? Do you have to swap cluster? Or just for vanity? I found that retaining my 3 spd 4WD auto box speedo cable and fitting it to the 5 speed d/r manual that the speedo then got a bit retarted and took time to catch up with real time/speed. That is what I should have swapped when i had the dash apart ....maybe do a test fit before you get stuck into it

T'subaru · Post by **T'subaru** » Mon Nov 23, 2009 2:09 am

steptoe wrote:there is something in the ECU 3 plug diagram, so not yours, with regards to manual or auto, simply earthed or not earthed on one pin. Maybe check this with 4 plug ECU pin diagram? Do you have to swap cluster? Or just for vanity? I found that retaining my 3 spd 4WD auto box speedo cable and fitting it to the 5 speed d/r manual that the speedo then got a bit retarted and took time to catch up with real time/speed. That is what I should have swapped when i had the dash apart ....maybe do a test fit before you get stuck into it

Honestly, the electrical is confusing until I have the time to jump into it. I have pin out diagrahms and I think I can power thru it, it's just very foreign to me at this time. I would like to retain the cluster in the rx if possible. The wagon has a trashed 4 speed auto and transferring the rx's drive train will give me a winter ride and allow me to tear down the rx for a full restoration.

steptoe · Post by **steptoe** » Mon Nov 23, 2009 11:42 am

4 sp auto, you most likely have the 4 plug ECU and a sep TCU for the auto. The 3 plug diagram has pin 31 , AT/MT discriminiation, a switch that connects a few things or not depending on its gender. Not found a description for which is which in the manuals. I don't use the ECU in mine 86 GLTA now manual as I use LPG Impco systems which really only need O2 sensor for the Impco commander box to do the rich lean stuff, so never went looking to see what connected to what.

wagonist · Post by **wagonist** » Tue Dec 01, 2009 3:46 pm

You're going from an auto to manual, that's certainly the easier way.

Don't be too worried about the wiring, and you should be able to do it without removing the dashboard, or even changing it.

For the wiring, really the only things you need to hook up are the reverse light wires & bypass the neutral safety switch.
Both of these are accessable around the gearstick.

For the neutral safety switch, there will be 2 thicker wires, one is black with white strip, the other is black with yellow stripe. Simply hook these together permanently.

For the reverse light wires, I think they are both green with stripes (can't remember what colour).
Using a multimeter or test light, find which wire has +12V when the ignition is on, this will be the power for the lights.
To find the wire to the reverse lights, get a piece of wire and then start bridging the power wire over until you find the one that turns on the reverse lights.

The easiest way is to then extend these wires through to the engine bay to the gearbox. I have seen it done where the wires went down through the fllor & wre then cable tied (within a shield) to the handbrake cable to keep them from getting caught up in the shifter mechanism & driveshafts.

Just hook each of these wires to each side of the reverse switch on the manual gearbox.

Apart from changing over the shifter & the centre console, the other thing that's needed is to bolt up the clutch pedal (not sure how hard that is to do on a LHD), and the best way to fit the smaller brake pedal is to remove the rubber pad off the manual version & simply cut down the auto one with a hacksaw, then fit the smaller pad over the top.

The rest is unbolt & rebolt.