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Rb25det vl wiring

Started by Dinodore · 26 Aug 2013 · 28 replies

Preserved from CalaisTurbo. Original authors and dates are shown; archived members are not current Holdcom accounts. View original archive ↗

DinodoreArchived member
Could anybody give me a rundown on what i need to wire up? Just so I can start it up.
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Ant_manArchived member
First thing i need to know is if its a series 1 or series 2 rb25 loom easiest way to tell is by the relays next to the ecu if has 2 its a series 1 if has a single relay its a series 2 loom If all you want to do is start it with a standard ecu its fairly easy at the body connector under the air cond box connect up these wires vl rb25 Green - standard fuel pump signal to Black purple strip - fuel pump signal Fat black red strip - Switch power Thin black white strip - Constant power Blue white strip - Switch power with these wired in at body plug and everything on the rb25 connected such as afm cas etc it will start and run but if you want to wire it in properly here is a short run down. Alternator, Starter, Etc.: The easiest way to wire the driver’s side loom is to graft the RB30 loom onto the 25. Undo all the wires off the RB25 alternator, starter and oil pressure sender. • Remove all the tape and conduit shielding from the loom and separate the knock sensor wiring from the rest. • The knock sensors are the two sensors at the top of the block under the intake plenum. • Remove the RB25 alternator and bolt on the RB30 one. • Unplug the RB30's driver’s side loom from the car (or RB30 if you kept it attached) and attach it to the RB25's knock sensor wiring. Plug in the alternator and starter motor. You can use the RB25 starter with the RB30 wiring no worries. • Remove the RB30 oil pressure sender unit from the RB30 block and screw it in place of the one on the RB25. Plug it into the RB30 loom now on the RB25. • Cover the loom with the conduit wrapping and electrical tape to neaten it up. • Grab the main earth wire off the RB30 block and put it in place of the one from the RB25. Fuel Pump The fuel pump in an R33 is earthed through the ECU. Series 1 loom in the foot well plug (long white one ON THE ENGINE LOOM NOT THE CARS DASH\BODY LOOM) thin white/black - constant 12v thickish red - ign 12v through a pair of 6A diodes (or one big one making sure the silver bands face the way u want the current to flow) to stop voltage flowing backwards to ground. If you don't use diodes the ignition won't turn off. Black/red - ign 12v yellow/blue - tacho, using the pull up circuit already detailed. Light blue/white - ign 12v, it’s for the vct and 02 sensor black/purple - fuel pump relay control Dark blue/black - temp gauge grey/red - 12v under cranking There are only two wires needed to make the Engine start now. One needs constant power and the other needs ignition power. • ECU plugs white wire with black trace. Tap the constant power in to it. • Thick black wire with red trace (BR). Tap ignition power into this wire. Now if your fuel pump primes and shuts off after a few seconds you've done it correctly. At this stage the engine should run if everything else is done. Tachometer • Find tacho signal wire from the dash plug. • Coming out of pin 7 on the ECU is a yellow wire with red trace (YR). This is the tacho signal to the ECU. You could splice a wire into this but I'd advice looking in the engine bay and finding a small rounded plug on the afm branch by the passenger strut tower. It has a single wire going into it and a rubber cap on the end. The wire is yellow with blue trace (YL). This is also RPM signal. Attach to tacho signal wire. • Now you'll need to go grab a 10k resistor. You'll need to splice a wire into wire 49 from the ECU, run it through your resistor, and finally splice it into the tacho signal wire.
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DinodoreArchived member
So the first colours are wires on the ecu plug? And you go straight from the colours you said to the black plugs udner the glovebox? It is a series 2 I believe as it has no igniter pack on the coil cover Also, where do I get the constant power and the switch power from?
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Ant_manArchived member
On the rb25 loom about 20cm from the ecu is a 10cm long white body plug in that is the coloured wires i described that need connecting to the vl body loom under the a/c there is several green wires one is for the fuel pump trigger , pink wires that are switch power and for constant power i ran a new wire To find the correct green wire on the blue plug under a/c, the green wire next to the orange with no strip is fuel pump signal
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DinodoreArchived member
Correct green wire on the *black plug? ya confusing me haha. Can you format it like this: Plug-Wire to Plug-Wire For a durry like me :P
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Ant_manArchived member
http://rb30det.info/wp-content/uploa.../02/plugs2.jpg (http://rb30det.info/wp-content/uploads/2009/02/plugs2.jpg) http://www.google.com.au/imgres?imgurl=http%3A%2F%2Frb30det.info%2Fwp-content%2Fuploads%2F2009%2F02%2Fplugs2.jpg&imgrefu rl=http%3A%2F%2Fwww.calaisturbo.com.au%2Farchive%2 Findex.php%2Ft-256466.html&docid=757lFtHeIyn5fM&tbnid=qXHmB-bJu6sTFM%3A&w=676&h=999&ei=0V8bUoyMNYe6kQWkv4DADw& ved=0CAIQxiAwAA&iact=c#imgdii=_ (http://www.google.com.au/imgres?imgurl=http%3A%2F%2Frb30det.info%2Fwp-content%2Fuploads%2F2009%2F02%2Fplugs2.jpg&imgrefurl=http%3A%2F%2Fwww.calaisturbo.com.au%2Farchive%2Findex.php%2Ft-256466.html&docid=757lFtHeIyn5fM&tbnid=qXHmB-bJu6sTFM%3A&w=676&h=999&ei=0V8bUoyMNYe6kQWkv4DADw&ved=0CAIQxiAwAA&iact=c#imgdii=_)
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DinodoreArchived member
Nice! cheers for that image of the plugs, the rb30det.info link doesnt work for me tho for some reason. Only thing I'm having trouble with now is the alternator wiring I can swap the plugs over easy enough, but im using the rb30 drivers side loom with the rb25 alternator so I was wondering if the leads that go to the bacxk of the alternator will bolt on? ---------- Post added 27-08-13 at 14:55 ---------- Actually yea I can't see the writing on the image because its too small, and the link gives an internal error :/ Some original photos have not been recovered yet.
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Ant_manArchived member
I made my own alt loom i used the rb25 loom as it has the iac, ficd, cold start, knock sensors etc with a new power wire to the alternator i also used the 25 alt as its 90 amp You will need to run a separate earth from the alternator to block. The brown plug has 2 wires, Red/White (top connection), goes to dash for voltmeter & charge light. The other wire Green (bottom connection), goes to the battery +, this is the charge regulator. ---------- Post added 27-08-13 at 18:58 ---------- The blue plug Top green is fuel pump signal connect to the black purple strip on white rb25 body connector Bottom right green is a/c signal thats all i used on this plug The black plug Top left brown is alt light signal which i ran from the alt red/white wire through with the engine loom to body connector and connected to the brown Top row green is temp gauge connect to dark blue black strip on the white rb25 body connector Top row blue is oil pressure i used the rb30 sensor and also ran the wire through the engine loom to the body connector Top row right brown/red is tacho connect to the yellow red strip with a pull up resistor Pink wire i used as switch power for the fat black red strip in rb25 body connect 2nd Pink wire i used as switcd power for the light blue white strip in rb25 body connect this is for vct , o2 sensor, afm power I ran a new constant power to the thin black white strip which runs to the ecu relay The solid black are all earths which i put on an eye let then screwed to clean matal somewhere near ecu.
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DinodoreArchived member
Legend! ---------- Post added 27-08-13 at 22:13 ---------- U just made my job so much easier
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Ant_manArchived member
http://wiki.r31skylineclub.com/index...r_near_ecu.gif (http://wiki.r31skylineclub.com/index.php/File:Rb25det_connector_near_ecu.gif) Here is a pic of the body connector with some of the wires marked ---------- Post added 27-08-13 at 19:47 ---------- Yep took me a bit of time to get all the info needed in order to wire it up my self so i was happy with the job done happy to try n help
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DinodoreArchived member
With the rb25det alternator, im using the rb30 wiring so the only thing I should have to change is the plug in the back of the alternator right?
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SteveArchived member
Don't forget to run a start signal wire to the ecu, which connects to the purple wire for your starter motor signal Grey wire with red stripe as mentioned here http://wiki.r31skylineclub.com/index...ET_into_an_R31 (http://wiki.r31skylineclub.com/index.php/Wiring_an_RB25DET_into_an_R31)
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DinodoreArchived member
Quote: Originally Posted by Steve [View Post] Don't forget to run a start signal wire to the ecu, which connects to the purple wire for your starter motor signal Grey wire with red stripe as mentioned here http://wiki.r31skylineclub.com/index...ET_into_an_R31 (http://wiki.r31skylineclub.com/index.php/Wiring_an_RB25DET_into_an_R31) Thats just for helping it start right? Giving it more fuel ---------- Post added 28-08-13 at 18:47 ---------- Where do I find said purple wire? ---------- Post added 28-08-13 at 18:48 ---------- Or can i use a wire off the white body plug as said here? "The 12v source can be taken from the body loom plug. The plug is the bigger of the two and the wire you need is black with a yellow stripe. "
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SteveArchived member
It will start without it, but is a bitch when cold. The purple wire that is in the factory vl loom that runs to your starter motor. Which is the same one used for the factory auto neutral start relays, which you bridge when you do a manual conversion. The link I posted is to the r31skyline site, so naturally the wiring colours won't be the same as a VL's wiring...
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DinodoreArchived member
Oh woops haha cheers for that. Thanks to u guys I should be able to get it running this weekend. But then it will have no wof till I get certification the engine... fml..
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DinodoreArchived member
Where does the blue white strip wire on the blue plug go? ---------- Post added 31-08-13 at 13:24 ---------- Also, the fat orange in the same plug, what is it for?
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PSI086Archived member
I presume you mean on either the blue or purple underdash plug in the VL? The blue with white stripe is the starter signal wire that goes from the 2 pin plug on the starter to the ecu and the fat orange one is just constant 12v. If you are using a skyline starter the wire will most likely be a different colour Don't forget to swap the single pin coolant temp sender to a VL one so the dash will read correctly
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DinodoreArchived member
The blue white strip goes to a plug next to the starter motor not actually in the starter motor so im confused about that. Im guessing I dont need the orange ones for the rb25? ---------- Post added 31-08-13 at 15:01 ---------- Quote: Originally Posted by Ant_man [View Post] I made my own alt loom i used the rb25 loom as it has the iac, ficd, cold start, knock sensors etc with a new power wire to the alternator i also used the 25 alt as its 90 amp You will need to run a separate earth from the alternator to block. The brown plug has 2 wires, Red/White (top connection), goes to dash for voltmeter & charge light. The other wire Green (bottom connection), goes to the battery +, this is the charge regulator. ---------- Post added 27-08-13 at 18:58 ---------- The blue plug Top green is fuel pump signal connect to the black purple strip on white rb25 body connector Bottom right green is a/c signal thats all i used on this plug The black plug Top left brown is alt light signal which i ran from the alt red/white wire through with the engine loom to body connector and connected to the brown Top row green is temp gauge connect to dark blue black strip on the white rb25 body connector Top row blue is oil pressure i used the rb30 sensor and also ran the wire through the engine loom to the body connector Top row right brown/red is tacho connect to the yellow red strip with a pull up resistor Pink wire i used as switch power for the fat black red strip in rb25 body connect 2nd Pink wire i used as switcd power for the light blue white strip in rb25 body connect this is for vct , o2 sensor, afm power I ran a new constant power to the thin black white strip which runs to the ecu relay The solid black are all earths which i put on an eye let then screwed to clean matal somewhere near ecu. "I ran a new constant power to the thin black white strip which runs to the ecu relay" How do I tell which one of the white/black wires to connect into? They all look the same in the back of the blue ecu relay
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SteveArchived member
The link I posted tells you pretty much everything you need. Go to the smaller white plug and use the black/white wire there
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DinodoreArchived member
There is no black/white wire in the small white plug. ---------- Post added 31-08-13 at 16:28 ---------- I got told to tap constant power into the black white strip wire in the relay. The website says the white wire black strip on the long white plug You said the black/white wire in the smaller white plug. Which one is ittttttt
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