OMFG PWNED by Harness :(

[Five_5Zigen_4]

Okay..i've researched..i've read the write ups..i've downloaded the Service manuals for both a 95 240 and an 89 240.

Heres my issue:

I'm doing a motor swap from a 95 240 (KA24DE, obviously) into my older 89 240sx. I've got the harness, and i've read that you have to splice your old connector (the small white one) onto the new harness (replacing the larger white one...not to be confused with the actual ECU connector). Here is where my issue lies...My colors aren't matching up. For the most part, i've found the same colors, but there are others that i cannot find. I've been searching through the service manuals and i've found most of the wires and what they are for. but others, i just simply cannot find them on there, so i have no idea as to where they go, being as how certain colors aren't on the 95's harness. So if anyone here has been through this (and i know its been done many times over), i would love to hear any input or suggestions or w/e about what to do. I'm trying despeartely to get this baby running..I haven't driven it since i bought the car 2 months ago If anyone can help, i would be much appreciative. You can also email me if you like: [email protected].

Here are the colors and info that i have. These are the ones on the smaller plug that connects up above the ECU in the dash.

Blue/Green: ?
Orange: ?
Green: ?
Red/Yellow: to ecu
Red: Check Engine/to ecu
Grey/Blue

Green/Red: ?
Red/Green: ?
Green/White: ?
Yellow/Green: Speedo
Blue/Black: Fuel Inj #4?
Yellow/Red: Instr. Cluster (Tach)
Black: Ground
Light Green: EGR Solenoid
Grey: SCV Solenoid
Purple: Press. Reg. Solenoid

Basically, i'm to the point where im not sure if im even doing this correctly. Its my first time, and i just want to get it right. This will be quite the learning experience! So like i said..any help would be GREATLY appreciated.

Thanks a Billion and a half

~Jason

[NIK90s13]

Ok, without pulling my harness and going over the color code, this is what you do, and trust me I just did the sohc to dohc swap 3or4 weeks ago. All you need to do is match colors from one harness to the other. there are wires that do not match to each on ether side of the harness. Just tape them off and forget them! Be sure to match every wire that will match.I think it's like 7ea wires that match.
I would use heat shrink and soulder the wires for best voltage. Also, if you have the time and can get the harness end, I made a ''pigtail'' between the 2 ends without cutting either harness, but that is not nessary, it was cleaner to me I just didnt like cutting the end off of either harness, but that is just me.
I know it seems wierd, but match the colors, and you are fine.

[Five_5Zigen_4]

okay....fwew....i was thinking that you would need to used ALL the wires off the old connector. Thats a sigh of relief lol. So does everything work for you then?? (ie: SPeedo, tach, etc)

[NIK90s13]

Yea works like it should, no problems. BUT if you don't know, your old tach will not work with the new motor, you will need the tach out of a dohc car/ or change the cluster to the dohc cluster, I switched tachs to keep the 115mph speedo in the sohc cluster. The dohc cluster is 110mph, Either will work.
The wireing seem wierd and I was just as leary of it but if you just match colors and disregard the others,get the tach, you will be running.
How far are you along in the swap? What have you done so far?

[Five_5Zigen_4]

Well, today im heading over to drop the motor in. I have a nice and clean DOHC awaiting its new home. I've removed the old motor, removed all the AC lines, emissions b/s, etc...cleaned up and painted the engine by, all in preperation for the install. I got a EGR Block off plate for the motor, and i've ran the harness through the firewall. Now, another question i have, is I've heard of an upper and lower harness...lower being for the tranny, etc...Any clues as to if i'm going to need another harness or gerry rig something up? Also, as far as the lights, etc...should that all plug and play? Or will i have to fabricate something there?

Oh, lol, and one more thing. I noticed that the connection for the exhaust manifold onto the exhaust is different...so i'm assuming i will have to replace the header as well?? (or w/e you wanna call it). I'm such a newb. haha

I've also yanked out my stereo from my tahoe to be sold, so im taking the power wire and ground cable for my amps and using that to relocate my batter (I have a stinger dry-cell) into the trunk (I have a coupe ). I'm hoping and praying that i can get her to at least run this weekend...i'm also kind of concerned about the tranny/clutch...the original owner was saying something about the clutch missing parts, but when we pulled the old motor, it seemed to look fine. But the clutch pedal would push to the floor, and stay there. I'm just hoping it was a bleeding issue and will be solved easily. Im really crossing my fingers here...

[NIK90s13]

No, the lights are a different harness. The lower harness will swap over from the tranny to the main harness. Mine did. Yes you will need the dohc exhaust manifold,or after market header, but it will bolt to the rest of the exhaust no problem.
You should get it turning over this weekend!!!! I blocked off the egr as will, it is alot easier to do with the motor out!!!! Please post your progress!!! Photos too if you can!!!
Dude I'm excided for you.

[Five_5Zigen_4]

HAHAHAH thanks man...i got some photo's but i gotta wait till my buddy gets home from work so i can get them from him. The motor is IN!!! Not without its complications, but hey, it happens! Now...the one problem (BIG problem) I'm having is electrical. Everything works as it should...lights, signals, etc etc. But i think i have a short some where. First reason is because everything works...WITHOUT the key being in the on-position. Also, the cluster lights (such as the open-door light, etc) stay on. And the big reason is i get CRAZY sparks when i connect the positive battery cable. VERY crazy..its practically welding on the battery terminal, its that bad. Eventually after trying to diagnose it, i blew one of the fuses in the engine bay (The 75A fuse on the fuse box on the passenger side of the engine bay). We also noticed that stuff stopped working, such as the starter "click", the pop up lights (lights would come on, just no motor) as well as the signals, etc. We tried jumpering the fuse location, and it sparked heavily and the wire got very hot. So, as i stated, i believe i have a short...SOMEWHERE...god only knows where....so yeah, if anyone can lend a hand or some advice, i would greatly appreciate it!!

btw, here's a vid i made when i first bought the car lol..it was before i decided to do the swap to DOHC (i didnt know about the guy sellin the motor). Basically, i was replacing the headgasket, and just about every other gasket on the motor.
http://videos.streetfire.net/player....8-6F86A8052C5F

BTW, Pics comming soon!! Gotta upload em

[NIK90s13]

Dont take this the wrong way, but at any time, was the battery hooked up backwards? Recheck the battery relocation setup.
My buddy trashed his 300z a wile back and decided to put his newer batt in my cay. Well the post were hooked up backwards and it sparked when he hooked it up. It poped that big 75 amp fuse(alt fuse) and a hand full of others. I had all kinds of electrical grimlins till I got the fuse thing sorted out. Oh and he bought me and optma batt too!!! Good friend!!!
I'd start at the battery, and check to see if any thing else is shorted out. Keep posring!!

[Five_5Zigen_4]

Okay..i think i've narrowed down the problem. I believe my friend decided to hook up the power line for the starter...to the alternator....that, and the two white wires that go to the alternator had been dyked off. I was going through the wiring diagrams in my chilton, and it showed a white and white/red wire going to the alternator. So my other friend said um..yeah...thats not right. LOL So we'll see..gonna check the FSM for more info.

[NIK90s13]

Cool, I guess you are still on the wireing then. Let me know when you get it going, or when you get to the next problem!! LOL!!!

[Five_5Zigen_4]

Okay...new update on the wiring issue. So i've figured out that the white and white/red wires go to the plug for the alternator, which, incidentally have been dyked off. I'm still getting crazy sparks when i go to jump the 75a fuse location (i blew the fuse), so im thinking im still getting too much power thorough there. But some neww issues have arrived..go figure..

First off, im getting no fuel and no spark. I've ohmed out the wires going from the fuel pump relay back to the fuel pump, and i am getting an open. I metered the fuel pump its self, and that is fine. So its between the stock s13 fuel pump connector at the fuel pump end and the relay. I isolated the circut by removing the relay and jumpering the contacts in an effort to close the circuit. I then metered it and still had an open. So i think i may have a cut wire somewhere along the line..not too sure. I'm thinking about splicing in some new wires to run back to that connector on teh fuel pump end and see what that gives me.

But...that also makes me quesiton the ECU, because im getting no spark, as well as no fuel. WHen i jumper the Alt fuse, i get my interior lights, wipers, etc to work. When its open, i get nothing on the inside. But my motor DOES turn over, so the starter is working fine. I checked the ECU pin numbers and found that pin 8 on a 95 DOHC ecu is for the fuel pump relay, 56 is for the ECCS relay, and pin 113 is the constant power to the ECU. I'm wondering if the ecu is NOT coming online, thus not providing power to the Fuel pump relay. So basically, im in a real pickle here. I have no other ECU to try out on the system, so im kind of lost as where i should start with this. Any info you guys can give would be GREATLY appreciated

Thanks again!

~Jason

[yokotas13]

take a power wire, from the battery with an inline fuse, to a switch on the inside, to the fuel pump power wire (the relay) Turn the damn switch on and you have fuel. That will tell you if your ECU is bad of fuel pump

[NIK90s13]

You do have the dohc ecu,Right? Yea, You do, I reread your last thread, Try yokota^ said, that will give you an indication.

[Five_5Zigen_4]

Yeah, i do...

So here's what i've got so far...

Your ignition sends out the signal and branches off into two contacts on the Fuel Pump Relay: 1 for the ecu which allows power to the relay, and the other that goes through the switch of the relay (which is flipped by applying power via ignition/ecu), out to the Fuel Pump, which then essentially has 3 grounds on it. I also found that there is the ECCS relay connector, which is a smaller blue connector on the inside by the ecu and dash harness...im guessing this is going to need to be plugged in to allow power to the ECU? If so, that is probably one of the main issues at hand, and i'm going to have to figure out where that is going to get wired to. That or i could just always wire up a bunch of switches LOL. ECU? Check...Fuel...Check...lol So yeah...thats about where i'm at now...im probably going to go out and look at it tomorrow and see what i can figure out. I've been digging all through the FSM's for the 95 240's and searching down all the different wires and connectors. If anybody has any input here, it would be, once again, very appreciated! I have approximately 2 weeks untill this thing needs to be in running order! Damn time constraints o_O

[NIK90s13]

I'll check for the ''blue'' connector by the ecu in the morning and see what I can find. It's to lste to think!!LOL

[Five_5Zigen_4]

Yeah, i found out its the ECU relay, which i went out and purchased one, but i'm still having the same issues

[Five_5Zigen_4]

So after a long time of not being able to work on the 240, im back in action...yet still with the same issues. Someone ended up sending me a bunch of notes that they had taken during their swap of a s14 DE into an s13 chassis....Now, according to that, i have to splice in the F8 and F9 connector from the old s13 harness into the new s14 wiring harness. The only bad thing is, albeit its laid out quite nicely, with a chart of all the wires and what they are on each side of the house (s13/s14), but i've found that some of the wires dont match up to what is written down. I'm really starting to wonder about this whole swap. I've had the car for over 6 months and have not been able to drive it yet, and i dont have a whole lot of time to actually sit down with the car, which is very unfortunate, cause i love my baby!! But anyway, i just wanted to bump this thread up a bit and see if anyone has any other suggestions or knows of anything else that i'll need to do in order to get her running.


Thanks guys

~Jason

[downshift_sideways]

Hey man, to be honest I was having the SAME exact problem.
I did an sohc-dohc swap.

Make sure all the vacuum lines are good, Check ALL the grounds, and make sure they are grounded properly. Check all the fuses in the Relay, and fuse box. Chec k all the fuses next to the clutch pedal. Make sure all your harness's on the engine is connected correctly. Did you get the dohc coil? make sure thats installed. get the dohc ecu.

Like thehy mentioned earlier, snip the sohc clip that goes into the daah, and snip the dohc clip and match up all the wires. There will be some left alone, just eletric tape them up.

Read your ecu Codes, too see if they can pinpoint out a certain location.
Use a voltemeter on your main eletrical. Starter,alternator battery, check your spark plugs and make sure they are good.check your dizzy cap.

check your relay clip, shoud be the blue clip located on the passenger side light, make sure thats good. You can also put a paper clip in the relay clip just to creat a circut, it will work temporarily or untill you get a new relay clip.

if you have any other questions just give me a holla

what motivated me, I had a afriend at a shop who has direct + and - tool, which feeds either + or _ battery. We connected the + to the starter and it cranked over, so it motivated me to keep on working.
Took me 5 months, but my apt manager wanted me to stop working on my car, or else she would tow it, so i had to get rid of it.

[Five_5Zigen_4]

We're you using an s13 or s14 engine/ecu/harness?

[NIK90s13]

hey ''5zigen'' still fighten it? Do you know what year motor you put in? You need the 91 to 93 ecu for s13 dohc motor, as for the s14 I'm not sure, I know you need to change the distrobuter and the lower intake from the s14 to the s13 dohc. Dude it sucks you are having this trouble, hope we can get you up and running!!!

[Five_5Zigen_4]

Yeah, im running a 95 DOHC motor. So i absolutely HAVE to run the lower intake and the external coil dizzy with this swap? Even though I have a 95 ECU/Harness and the 95 motor?