FC3Sdrift

iTrader: (5)

I'm making this up as a referance on how to do this, It's not a direct guide on how to do this.I highly reccomend having both S4 and S5 ECU pinouts printed out for quick referance when your under the dash...I still haven't got my totally finished but it is running.....i will add more add i finish mine off...i did have to switch the p/s pressure sensor and splice on the S5 end for the water thermosensor

first off You need a S5 and S4 engine harness,
S4 Harness
unwrap the S4 harness completely measur how far the 2 FEM plugs are from the ecu connection.... the one FEM plug has only 2 wires actually connected to the harness a ground and some solenoid the rest are a direct connection to the wiper motor and cruise control...snip the 2 wires , mark which one is the ground so you can tie it back into the S5 harness ....the Second harness you will see there is 3 wires goin to the "3b" pin Starter switch, "3D" fuel pump resistor relay, "3J" battery. Cut those closer to the plug that connects to the ecu because you have to connect those to the chassis harness plug for the S5 ecu.
The rest just go through the wiring diagrams to find out which are grounds and whats not needed...alot of it isn't needed on the S5 harness

S5 Harness
I used the Jdm RHD harness that came with my engine its the same length as the S4 harness just wrapped differently. but i unwrapped it about 3/4 of the way starting at the ecu plugs,start tracing the wires off the S5 FEM plug, mark them as you cut them you'll notice that the colour combination is similiar,once you have the S5 FEM plug seperated from the find out where your S4 FEM plugs will sit. Start off with the one with the wiper blade plugs find a ground to splice into then wrap some tape around it to hold it in place then start splicing in the needed wires for the second plug....you will have to run a wire off one of the black with white stripe wires and put it with the three wires that from the S4 #3 plug....You will have to cut the wires for the crank position sensor leaves enough to easily work with
i bought some of the plastic wire cover and some good high heat resistant electrical tape....rewrapped the harness all nice and pretty. as for the ruber grommet where it passed through firewall I had to cut it but i just wrapped it with tape ...it works it was the best i could come up with....if you have enough patience to feed the wires through it would be better. In the end you should have a complete harness with the 4 wires for the battery,main relay, fuelpump relay,and starter swtich hanging out and the 3 for the crank positon sensor

I ran it along the engine how it was originally layed out ...i had to extend the wires for the primary injectors because the harness was siting alittle farther back and it was alittle tight under the UIM...then i ran the engine harness along the firewall into the hole in the firewall

Under The Dash
For the chassis harness plug that goes into the ecu:
Start with the S4 plug thats in your car find the 4 wires for the crank position sensor and put the red and blue wire together and connect it to them 3H pin green to the 3G pin white to 3E pin on the S5 plug
Get your S5 #1 plug and start splicing...don't cut a wire off the S4 Plug till your totally sure its the right one
heres the pins i switched

S5-->S4

1A-3J
1B-3I
1C-3B
1D-1D
1E-1A
1F-1B
1G-1X
1H-1V
1I-1J
1J-1U
1K-3D
1L-1F
1M-1C
1N-1R
1O-1E
1P-1W
1Q-1L
1R-1G
1T-1I
1V-1M

Get a S5 TII N370 boost sensor and a S5 AFM, S5 rad or Remote filler neck and your good to go

I'll add more as i go ....but for now heres some basic guidelines to get your car up and goin ...you still have to do some stuff for yourself but....once you get goin its actually pretty easy just alittle bit of splicing make sure you solder all your connections and i like to get that shrink wrap and put them on all my connections so you know you won't have any problems, also as you go keep and eye out for any pinched wires or possible shorts to save you problems in the future


Post up how you guys make out with your projects doin it like this
hope it helps.....i was just doin this on my own with alittle help from a select few

HAILERS

Does the series five JDM EM harness have but one plug that interfaces b/t the Front and EM harness???? Like the series four has the two plugs FEM-01 and FEM-02 up there near the firewall. The JDM have but one there?????????? instead of the two? Just curious.

NZConvertible

Your extensive work pretty much shows why this shouldn't be done. There's very little advantage to using an S5 ECU and harness in an S4, and there's no advantage at all to using a RHD harness in a LHD car. IMO both just create a lot of extra, unnecessary work.

phoenix7

plug-and-Play FTW! post your work in better detail and maybe this will be archived for anyone else who might wanna add time to their swaps.

RotaryResurrection

iTrader: (8)

Your work is largely irrelevant, as you used a JSPEC engine harness for the swap which is missing several wires and one entire large plug versus the north american harnesses we work with.

FC3Sdrift

iTrader: (5)

theres about 3 hours worth of work switching this ....the advantage is you don't have to tear apart the front cover and risk screwing up the bearing

There are no essential wires missing if you splice the S4 FEM 01, FEM02 plugs to the s5 harness
It wouldn't matter if you had the RHD or LHD harness....i had the RHD harness so thats what i used
i'll add some more to this on the weekend

FC3Sdrift

iTrader: (5)

my JDM harness only had one FEM plug but the S4 had 2

FC3Sdrift

iTrader: (5)

would that be the 7 wires i had sticking out at the ecu side of the engine harness that i ran in into the #1 chassis harness ecu plug ......for the battery,main relay,ignition switch,fuel pump resistor relay and the 3 Crank Postion Sensor wires

AR Rotary

iTrader: (3)

Thanks for the writeup. Its helped me. I know everyone has their opinion about this subject but N370 harnesses are nearly impossible to find locally and getting very scarce on the board. You make do with what you have sometimes.

HAILERS

Thank you for the reply.

It sounds like the plug called FEM-01 (or X-15) is probably the one missing in action. It does MOSTLY the wiper, cruise control, aux fan temp sensor, subzero, etc. Or I should say has the wiring for thosse on a USA.

Like in this jpg: https://www.rx7club.com/forum/attach...3&d=1187795982

I do think if I had a JDM engine with electric OMP(going into a series four), and the thing came with a series five ECU etc, I'd *rearrange* the wiring like you did so the S5 ECU and OMP would work. Rearrange and splice and solder etc.

pdtaylor18

This is what I was faced with when i brought my car. I took all the pain out by simply replacing the entire harness with a S5 one. Took maybe all day but the only way. By the way this was a S4 JDM Vert to a S5 UK spec vert. A lot of plug were different and more so all the internal electrical boxes etc. At least now i have a completely UK car in terms of electrics. Even the headlight wiring is different due to the FTP lenses and sidelights. fun but well worth it.

FC3Sdrift

iTrader: (5)

your in the UK though....you don't have the RHD to LHD problem

FC3Sdrift

iTrader: (5)

did any one get a chance to second my work?

AR Rotary

iTrader: (3)

Working on it right now.

dirteeboy808

iTrader: (3)

Is splicing same with the USDM wire harness?

FC3Sdrift

iTrader: (5)

I would think so. I used the U.S FSM as a referance when i did mine
its all about showing the ecu what it wants to see..if everything looks good to it , its happy

FC3Sdrift

iTrader: (5)

my stock boost gauge even works!!!!
i finallygot myboost sensor.....i let my car run for a bit today....runs good....needs a tune up to get it running mint

no smoke atleast...she starts nice and easy now...never had to bump start it...but i did have to get new plugs


heres a video of it running....needs some tweaking ...but atleast it runs
it has a open down pipe ...i need a fmic and exhaust...right now i have the piping routed straight to the intake.....i'm not driving it or building boost in the driveway so it'll be fine for now

let me know what you guys think http://www.youtube.com/watch?v=4mGlUB_yH7o

dirteeboy808

iTrader: (3)

just wondering how this setup was doing? May have to start mine after the new year.....=)

FC3Sdrift

iTrader: (5)

pretty good so far....havin a few troubles getting it to idle down...but its not a problem with the set up....just a normal rx7 gremlins

mine starts up first try in the mornings ....but i'm having problems....it won't stay running below 2k...2k and up revs fine....but i've found other people with the exact same problem...so its just a normal rx7 problem.....i think its shitty fuel and crap in the system.....i've been workin some seafoam through it each day it seams better ....so maybe its just that its needs to be ran to clean it out....i dunno though...i'll let you guys know when it get all the bugs worked out

FC3Sdrift

iTrader: (5)

so rather than splicing maybe a total of about 30 wires to get a series 5 engine to work in a seires 4 car with an ecu that its tuned correctly for the engine and will run the MOP if you knew what you were doin you could do it all in an hour or two ..its less work to completely strip off all the sensors...pull the front cover off, change to a mechanical MOP risk screwing up the front bearing or having problems with the oil seals....change to a S4 water pump and clutchfan,,,then switch all the fuel injectors and UIM and TB only to run a computer that isn't actually tuned for the engine so it will never run to its full potential....if i had a garage and i was charging by the hour i guess i would tell everyone running it with S4 electronics is better....but those of us who know how to work a soldering iron and down feel like stripping the whole engine just to get it running half assed right might do it my way

find me any SR20DET swap guides that doesn't show splicing the engine harnesses together as the accepted way

clived

this might help

Not sure why it wont work now, direct link is posted

clived

http://i461.photobucket.com/albums/q...DASHPINOUT.jpg

clived

"you will have to run a wire off one of the black with white stripe wires and put it with the three wires that from the S4 #3 plug....You will have to cut the wires for the crank position sensor leaves enough to easily work with"

Ok, I'm lost, aren't the "crank" position sensor wires in the s5 harness wiring, going right to were they need to go, the ecu? Why would you need to cut them out and rewire anything?
From what I see, the crank angle sensor is hooked into 3G, 3H and 3E, of the s5 harness.

FC3Sdrift

iTrader: (5)

when first wired it up i had tried using the S5 CAS wires and it wouldnt get fuel or spark i cant remember which one, if you want it to work you have to splice in the S4 CAS wires so it'll work

**note for any one doin this into a N/A chassis, you have to run the wire for the alt , i found out they are in the engine harness, but are on the chassis harness for the TII's

Mr.JTurboII

Bump From Hell, But in theory, this should work backwards right? s5 chassis harness into an s4 ecu