DCCD problem after transplant to WRX - Neetronics Controller.. Please help!!!
 

Hi All,

Really got an issue here.... Let me explain.

Got a Type R gearbox with DCCD and diff fitted to my 1995 WRX. I have wired in a neetronics dccd controller. When i picked the car up i had some cluncking from the rear diff which i belive to be normal but it soon became apparent that the center diff was compleatly locked as i getting some horible sounds moving round shap corners and such. I stopped and disconnected the power feed to the box and unplugged the Neetronics DCCD controller to try and open up the center diff but no diffrents!!

Guess what im asking is..

1) what could cause this?
2) Can anyone tell me what wire does what on the box its self.

Please correct me if im wrong but the only way i can see for this to happen is if the center diff is getting a voltage causing it to lock...? Is this correct?

If i am correct then i guess that the box/dccd controller has been wired up wrong??

Lots of questions and i hope u guys have lots of answers.

Cheers in advance.

Scooby Luke

Ask John Stevenson if he's got a spare minute to listen to your probs. He's fitted one quite recently. Even better, phone Andy at Neetronics.......

Is john on here doug? You think he would mind me pm'ing him?

Thanx for your quick reply. It was to dark to have a look at the wireing on the box. As i say i have disconnected the Neetronics Controler compleatly and i have also disconnected the 12v power supply that i left for the garage to wire up to the box. But no luck, the drivetrain is locked up.

Let me know how you get on as i am going to get a Neetronics unit soon...Alan

Will do...

John can be found on Projects section and I think he has now fixed the settings on the Neetronics which are numerous.
Graham

Thanx 911, i have just pmed John. Im currently at work so i cant have a look at the car till 6. I think ill start by unplugging everything from the box and see if it runs open then.

How have you wired the neetronics unit to the gearbox dccd wires (bottom 2 on the 6 way connector clipped to the top of the gearbox near the dipstick.

There should be a wire from a 12v ignition switched supply to one, and the purple wire back to the neetronics box connected to the other, make sure the purple wire isn't grounded!

I am presuming you didn't buy the unit from the UK distributor then?

Andrew...

AndrewC, Thanx for your input.... i got a feeling it is somthing to do with the power feed.

Yeah the neetronics controller from the uk. I did the neetronics wiring and left the purple wire and red power wire for the garage to wire in when they fitted the box.... i think this may be the issue.

You wouldnt have a picture of which pins i need to check to make sure the purple and the red wires are hooked up to the right pins have you?

That info is on the Product site isn't it?

The non dccd car has a 4 way box connector and the dccd box 6.
I suspect that is where the fault is too.
Graham.

The neetronics website is quite hard to navigate round... i have spent quite some time trying to find information on it but the only useful thing i can find is a copy of the instructions which say.......

Purple DCCD out
The purple wire is to be connected to your vehicle’s DCCD.
The DCCD requires two wires to be connected in order to
operate. The purple wire provides a switch to the ground side
of the DCCD.

4’ Red Wire +12V
The extra 4’ red wire included with this kit is meant to be
connected to the other side of the DCCD (opposite of the
purple wire) to supply power.

Doesnt say which wires on the box (connector) they need to be attached to.

Connectors vary slightly although my UK 98 plugged straight into my 6speed dccd box but with 2 pins missing on the car side of the connector

You can see here the neetronics wiring into the connector on my car
http://www.teamcarr.pwp.blueyonder.c...CCD-wiring.jpg

Thank you AndrewC... that is very helpful... Will report back and let you know what i find.

I know im going to sound stupid now but i want to get my head around what is happening within the diff.

Please correct me if im wrong...

As i understand it the dccd works by increasing voltage going to the diff which inturn increases the power of the magnets locking up the diff more?

So this means that if there is no voltage the diff should be compleatly open?

If this is the case how does that work when the box is getting a direct 12v feed? and how does the diff know how much lock to set from the purple wire.

From the Neetronics instructions "The purple wire is to be connected to your vehicle’s DCCD. The DCCD requires two wires to be connected in order to
operate. The purple wire provides a switch to the ground side
of the DCCD.."

Sorry for all the silly questions but i guess this stuff might be helpful for people other than my self.

Luke you are not quite right but you are not far off. With no voltage applied the diff is open, with 12v applied it is locked. Every ratio in between uses pulse width modulation. i.e. if if you apply voltage for 1/100sec then no voltage for the same period repeating the pattern, you get 50% diff lock

Thank you john, i understand how it works... now i just need to get it to work on my car tomorrow.

Will keep you all updated.

Excellent.

I went for the stock controller for just this (and cost) reasons, but in hindsight a Neetronics would have been the best option.
Be good to see how you get on and John too on the hills.
Graham.

I meant to post some close up pictures last night but ended up taking my 3 year old son to casualty - nothing serious just one of those stupid 3 year year old boy things!

Before anyone (John) comments those wires are now sleeved, I just took the pictures during the installation and testing.

Anyway larger picture and closeup here:
http://www.teamcarr.pwp.blueyonder.c...CCD-wiring.jpg
http://www.teamcarr.pwp.blueyonder.c...-connector.jpg

Andrew...

Andrew, my installation is still just 'bodged' into the car so I'm not in a position to be a smart arse right now ;)

My installation is pretty near perfect - not a wire in sight:

http://www.teamcarr.pwp.blueyonder.c...neetronics.jpg

Well the story continues...

Rang john today who was very helpful. He suggested getting the car up on axel stands and running the car with the hand brake on... if the centre diff is open it should just run the front wheels and not stall... if the diff is locked then the car should stall.

I turned everything off on the neetronics controller and set the thumbwheel from 0% to 100% lock. On 0% the front wheels drive while the hand brakes on. When on 100% the car wants to stall which would suggest the dccd is working and wired up correctly.

So I took the car out for a drive to see if things had sorted them selves out but its doing the exact same thing... on tight turns it judders and skips. I went to a local carpark to test this out. When moving off from stand still with the steering on full lock to the right, the right hand front wheel will actually lock up completely and making all manner of clonking from the rear... AHHHHH!!.

I fear i have spent alot of money on a broken box :( Next thing i guess is get it back to the garage i got the box fitted at and see what they think.

Is there any chance that something like the wrong rear diff ratio would do this?

Any advice would be much appreciated.

For additional info call David at Welcome to the API website tomorrow morning.

I used the same method to check mine as John has told you, but the advice came from AndyF with one difference, I used the foot brake.

It seems to my novice mind there is something worse going on.

Call David, tell him '911' sent you. Try about 9.00am before the masses arrive. He might be closed for the holiday, and if so email him as he watches most times all the mails.

Graham.

Luke what kind of front and rear diff are in the car ?

---john---

Hi all,

911 - I have emailed Dave... couldnt get through on the phone.

John - I was told it was the standard rear diff that came on the Sti 5 Type R's. I had to fit new hubs to take the bigger drive shafts. Does that indicate a R180 Diff?

That would suggest an R180 yes, and a plate diff at that, which might explain the clunking at the rear. It the front of the car is off the ground and you rotate one wheel by hand, which direction does the other rotate ?

Right... just to update.

Spoke to the guy i got the box from, he says that the diff and the box came from the same car so cant be a ratio issue.

The mechanic that install the box and diff said that it could be something as simple as tread being low on one of the back wheels... which it is. Ill get the tyre done today and report back.

I really will kick my self if its as simple as that.

Doubt personally that it is that!

me ether but its worth a go. Will let you know how i get on.

How much do you guys recon it would be to buy a center diff to replace the one in my box?

Easy, but you need the right one as I recal reading on here there are some differences in the trans over the years and the centre sections.
He does all my gearbox work, so i would suggest a chat to David at Welcome to the API website.
He has stacks of transmissions there.
Graham

I had the same problem when converting- without a shadow of a doubt you have mis-matched ratios- speak to David at API and get it resolved before it costs you a gearbox- fortunately I had a spare....

the guy that sold me a 'rear diff and gearbox (from a 96 STiRA) with dccd setup all from the same car' was talking through his arse- to my considerable cost.

exactly the symptoms you have reported, culminating in a 140mph bang at Aintree. if I understand it properly (not massively technical) forced the retaining circlip off the shaft that transfers drive to the front wheels.

http://www.grandprixweekender.com/photos/gearbox1.jpg

http://www.grandprixweekender.com/photos/gearbox2.jpg

http://www.grandprixweekender.com/photos/gearbox3.jpg