Man THa wiring doe slook insane i thougth that all teh ecu was hooked up to was teh injectors and all teh ideling shit adn the distributor well it seems the ca18det dosent have 1 but i wanted to do a swap . I dont knwo where to get teh motor adn i would liek to see how the harness looks. Wat wires did u have to cut adn reconnect
ive got my ET sitting on the garage floor next to the S12 and the DET sitting next to that..... this weekend the engine should be bolted in and hopefuly she should be up and running within the next month
I will be buying an S12 in the next few weeks and be using it for a daily driver while my s13 is off the road.
After my s13 is back on the road I will have a spare ca18det on the shed floor and will need something to put it in.......
Does anyone have the wiring details for the conversion? From what was said in this thread everything else is just "bolt in"
Nu-Delhey man
just slotted my CA18DET in today but the wireing is confusing the hell out of me even after looking at a S12 wireing diagrame nissan gave me it still makes no sence
which wires on the S12 join to which on the S13 loom cause ive found all the wires on the S13 loom you say to mark but i cant work out which wired on the S12 to join them to
thanks heaps in advance
i'm currently sorting this out my car also. since i'm building an all-out drifter/racer, there isn't a lot of wiring left anyway. i've just kept the important stuff like lights, starting sytem, charging system, and a small amount of the body elect. basically, you really need to adapt the CA18DET EFI harness to where the s12 one hooks up. and of course there's a few extra wires to hook for the speedo etc.
My speedometer worked when I didn't touch any wirings regarding the speedometer and the mechanical cable
The tach, water temp, oil pressure on the other hand didn't work or doesn't work properly
What year s12 are you guys working on?
If I remember correctly the wirings for pre 4/86 and after 5/86 are different
the wirings are also different between the N/A and Turbo motors
I have a 1986 service manual (September 1985 Edition) and can scan some pages for you guys if needed
I have a 1/86 200sx and this is what i did
I just grounded my fuel pump on to the chassis instead of hooking it up to the relay wire
I hooked up my ecu powers to an always hot source
hooked up ignition power to the ignition switch on
grounded a wire from the alternator to chassis because the connector to it doesn't ground it (blew a crap load of fusible links wondering where the short was)
connected quite a few more wires but can't remember off the top of my head...
Ask what you need wired and maybe I can remember...
I don't know about you guys but my harness doesn't reach the interior of the car so my ecu is in my engine bay
I had cut up all the tape and it didn't get any longer so I wasted half a roll of electrical tape and a hour taping it all together and making it neat again...
i think the US cars have different wiring again. as far as the w/shop manual i had was concerned (got it from a nissan dealer), it doesn't mention anything about the US cars (there's nothing on VG-powered cars either).
i'm doing a 1/85 car (MK1)
iquMy speedometer worked when I didn't touch any wirings regarding the speedometer and the mechanical cable
The tach, water temp, oil pressure on the other hand didn't work or doesn't work properly
Im about to put in a DET in my '88 with ET.
I have my S12 that is complete.
And i have a complete S13 '89 that i am going to take the engine from.
Why dont just use the whole harness from S13? Does the S13 ECU fits in my S12 harness? Cause my S13 has a stage 2 ECU.
not sure what stage 2 refers to...
it is actually easier to adapt the s13 ECU harness to the s12's main harness.
okay, im a little bit confused. maybe cause im ill and havent slept for two days (and yes, i work as a painter at daytime).
but is there anyone that can add me on msn, icq or aim? i would like to solve this harness thing. if there is anyone that has documents of making a ca18et/det-hybrid-harness thing and would like to share the info i would be very glad!
(sorry for my poor english, im reeeaaaally tired)
it's been a while but here's what i've come up with:
for a JDM s13 CA18DET going into an AUSDM s12 GL hatch i've began nutting out the wiring. i've started at the connectors where the EFI harness joins to the main harness on the left hand side of the engine bay.
Fuel Pump Relay: On the s12 harness, there is a Blue/Green wire that comes from the s12 ECU (6-pin plug), that goes to the relay. the S13 ECU no longer uses this wire, so you join it up to the Black/Red wire that goes to the relay from the 10A fuse in the fuse box. as for the two other wires that come out of the relay, one is earth (Black), the other (Red/Blue), goes to the s13 ECU. this wire joins to the Black/Pink wire in the s13 EFI harness. also, going off the S13 FSM, it appears that the 10A fuse will need to be swapped for a 20A, i will investigate this more further on.
Dropping Resistor: to hook the dropping resistor up, you need to join the Black/White wire on the s12 main harness (at the same 6-pin plug), to the red wire in the s13 EFI harness.
Start Signal Relay: to hook this up, bypass the boost switch/vacuum switch (it's the same thing) in the s12 setup, by joining the Yellow/Red to the Green/Red wire. this sends the start signal to the s13 ECU by joining the Green/Red(Yellow/Red wire) wire to the Orange wire in the s13 harness at the same 6-pin plug.
EFI Relay: At the same 6-pin plug as before, join the Light Green/Blue wire in the s12 harness to the Red/black wire in the s13 harness.
ECU 12V: At the same 6-pin plug, join the Black/Yellow wire from the s12 harness to the 2 Black/White wire in the s13 harness.
Note: you will find that there are a few of the same wires coming out the ecu harness, to help, i've included the s13 ECU pin layouts for these wires:
Fuel Pump Relay: 18
Ecu Relay: 16
Ecu 12V: 49 + 59
Start Signal: 43
looking at the front of the ECU plug (wires on the other side, with hump in middle of plug to the top), these wires are located as follows:
Top row: 101,102,103,104,105,106,107,108,1,2,3,4,5,6,7,8,9,10,21,22,23,24,25,26,27,28,29,
30,41,42,43,44,45,46,47,48,49,50.
Bottom row: 109,110,111,112,113,114,115,116,11,12,13,14,15,16,17,18,19,20,31,32,33,34,35,36,37,38,39,40,51,52,53,54,55,56,57,58,59,60.
PLEASE NOTE: this isn't all the wiring that's required to be done. also, THIS IS UNTESTED!!
if anyone thinks there should be ammendments made to this, please inform me asap.
a few adjustments:
Wires so far required from the s12:
Black/White, Ignition Power
Black/Yellow, Dropping resistor
Light Green/Black, EFI/ECCS relay
Light Green, Fuel pump relay
Red/Blue, Air Regulator
and from the s13:
Red/Black, ECCS Relay
Black/Yellow, Air Regulator
Black/Pink, Fuel pump relay
Black/White, ECU power source (12V ON)
Red, ECU back up power, Dropping resistor
Brown, Engine control (send voltage to O2 sensor, A.A.C. Valve, and pressure regulator solenoid).
Black/Red, Ignition power
if i've missed anything, please tell me.
also, start signal for ECU comes via orange wire at terminal 43, and sent to the Yellow/Red wire at start signal relay under dash on a-pillar.
found some more importatnt info on S12OC:
""Him" is me The DET swap is really easy, only the wiring was tricky. The S12's ECCS is totally different to the S13 so you need to make a lot of changes.
Firstly the S12 powers the fuel pump by running power to it and earthing the circuit via the ECU. This is to give variable pump speed. The S13 ECU powers a relay which supplies power to the pump which is then earthed...so in essence the circuit is the other way around. To wire this you need to install a relay and run the wires through the car to the pump. Just discard the original fuel pump wires in the car...it's easier to installnew ones.
Second, you need to install another relay to power the coils. This is reasonably straightforward and you can easily figure it out from the wiring diagram.
That third relay needed for the system is the EFI relay. The S12 already has one of these but the way it works is wrong for the S13 system. If you study both relevant wiring diagrams you will see what is needed to alter the circuit to use the existing relay. Without the info in front of me I can't remember the exact details but I remember moving one of the wires on the relay and joining it with another and then cutting a circuit on the bacl of the fuse box.
The knock sensor wiring and plug isn't present in the S13 engine harness...it's part of the car harness so you will have to add that in.
The rest of the wiring is no real problem. The only other thing I couldn't get working was the tacho. This is because the S12 has a single coil and the S13 has coil packs. There is a tach signal connection on the ECU but the signal doesn't seem strong enough to work the S12 tacho. The way round it is to take a wire off each coilpack with a diode in line and join the four together into one wire to run to the tacho. I've yet to do this on mine."
hope this helps, coz i know it'll help me!!