Wiring an s5 turbo tranny into an s4 n/a
 

:wallbash: Hey I'm trying to wire an s5 turbo tranny into an s4 n/a. Has anybody done this or know of a write up? The faq just says "adapt the wiring" which obviously isnt much help. I guess I'll start finding some wiring diagrams if I have to...

I put a turbo tranny in my s4 gxl... wasn't a whole lot of wiring that needed to be done... The only wires would be the neutral switch and the reverse lights.

The same switches are present in the same locations on all FC gearboxes (clearly shown in the FSM Transmission and Wiring Diagrams chapters), so you're just plugging stuff back in where it came from. The only adapting that might be need is for different connector types.

that doesnt sound right. the switches that came off the na tranny had like 6 wires plugged into them and the turbo ones only had 4. I'm just trying to figure out what to do with the 2 extra wires. If anyone can save me from staring at wiring diagrams I'll owe you one...

Damn, I looked at the 5th gear switch/backup light and I realized it doesnt have any wiring at all, just the 2 prongs that wires should plug onto. Either way, I still have no idea where these wires should go. I tried checking out the diagram in the fsm but I was having trouble finding it.

Also, I pulled the 5thgear/backup light switch on the turbo and compared it to the na and the turbo one is like 3 inches longer.

All FC manual gearboxes have a neutral switch (two wires) on the right side and a combined 5th/reverse switch (four wires) on the left side. Picture in FSM Manual Transmission chapter (page 7A-4).

All FC's have the same wire colours for these switches (FSM Wiring Diagrams chapter):
The neutral switch wires are green/black and black (page 50-28)
The 5th switch wires are black/blue and black (page 50-28)
The reverse switch wires are black/yellow and red/green (page 50-60)

Those colours are on the harness side of the plugs. The wires on the actual switches might be different. The neutral switch should be a no-brainer. If the reverse lights don't work, swap the pairs over on the 5th/reverse switch. Somebody else mught have a better way to identify which wire pairs are which.

Wow, good stuff. Your the man NZ. I ended up having to lengthen the wires a bit and using some of the old connectors but everything looks good for a tranny install tommorow. Thanks. :bluesuit:

Okay heres an update. I did all the wiring and such and installed the tranny. Started it up and my gauge cluster doesnt work nor do my reverse lights. switched the plugs and still nothing for the reverse lights. Although on the first start my buddy saw them go on for a couple seconds even though it wasnt in gear. I'm using an n/a speedo cable, do I need to change it? And what would cause my gauge cluster to not work? I'm stumped here, I'm gonna recheck the wiring but everything looked good.


Also, is it possible to criss cross the 2 wires for the neutral switch? Cause if so I may have done that.

These are just switches, so reversing the wire pairs will make no difference. Use a DMM to determine which wires on the fth/reverse switch are which. The wires for the 5th gear switch will have continiuty with the gearbox in 5th, and the wires for the reverse switch will have continiuty with the gearbox in reverse.

Check the 7.5A METER fuse; it powers the gauges and the reverse lights. You probably blew it with a wrong wire connection.

Did what you said and the gauge cluster works now, but for some reason the reverse lights stay on. If I switch the wires the fuse just blows. I can live without revers lights, I'll just unplug them no biggie. Thanks again.