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help installing weird FCD

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Old 08-09-04, 10:41 AM
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help installing weird FCD

Ok so I bought this FCD and I didn't know it didnt have a plug on it so its just got wires coming out. The wires are labeled: 12v, ground, V-REF, in, and out. I know what to do with the 12v and the ground, but where do I attach the V-REF, in, and out wires?

TIA

Tom
Old 08-09-04, 10:48 AM
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i have just got one that has 4 wires and a hand written wiring diagram

the only thing mine says is

1 - 12volts +
2 - 12volts -
3 - green/yellow loom side
4 - green/yellow plug side

now i know this isnt gonna help - but from what it sounds like is that you cut one wire on the boost sensor and wire one of the FCD wires to each end

what are the colours off all the wires and i will have a look to see if it matches mine

thanks

stu
Old 08-09-04, 10:54 AM
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ive got red, black, green, red with black stripe, and green with black stripe
Old 08-09-04, 12:41 PM
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Let me get this straight.... It didn't have a subharness that came with it so that you plug one side into the pressure sensor and one into the stock connector???????

You just got five wires sticking out of the thing right and a really BIG box and if you open the box there is a radioshack bug board with a lot of jumpers running around right??)

if so... this is what you got, if the guy built it right, it will work (for a while)

http://www.teamfc3s.org/info/articles/fcd/diy_fcd.htm

Now then... You will need to create yourself a harness... get 4 male and 4 female spade termanals

the In gets a female spade the OUT gets a male spade.

the 12v V-ref and Ground need to be "run Through" What you do is get a femal spade terminal and twist a jumper wire a few inches long onto the 12V, then crimp the terminal on (you've just made a terminal and added the throughput wire on at the same time. The end of the new wire gets a male terminal. Do this for V-Ref and Ground

THe male terminals go into the wiring harness connector and the females go into the boost sensor.

Here is the order Under side of boost sensor, clip notch to the top
Upper left = 12v Upper right = Ground
lower left = In Lower Right = v-ref

Wiring Harness connector Clip up

Upper Left = Ground Upper Right = 12v
Lower left = V-ref Lower Right = OUT

Whats going on here is that the FCD is taking in 12v, Ground and V-Ref and using them for its circuitry. By creating the Pass through wire, you are allowing the signals to go to the ecu unmolested. The In takes the output of the FCD, runs it through the processor chip, and then pukes it out to the out as a modified signal that goes to the ECU so that you don't see boost cut.

Last edited by YearsOfDecay; 08-09-04 at 12:46 PM.
Old 08-09-04, 12:50 PM
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****if so... this is what you got, if the guy built it right, it will work (for a while)****

Mine's been working over two years. The BIGBOX is located on the right fender to counter my weight on the left side of the car. humor, pleas.

My RacingBeat FCD resides in my other car. IT needed adjustment. It was set too low. Much lower than I like. Like 3.29 volts approx.
Old 08-09-04, 12:59 PM
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Originally Posted by HAILERS
****if so... this is what you got, if the guy built it right, it will work (for a while)****

Mine's been working over two years. The BIGBOX is located on the right fender to counter my weight on the left side of the car. humor, pleas.

My RacingBeat FCD resides in my other car. IT needed adjustment. It was set too low. Much lower than I like. Like 3.29 volts approx.
As long as the bug boards don't get wet or beat around, they will last quite a while, but the damn radioshack boards will corrode if they are exposed to too much humidity and fingerprints will kill em. I said the hell with it and started making PCB's for 'em, that way, the box can be about 1X1 and the board will last a long time.

I used to set the ones i make at 3.67 volts, and I had a couple of people get boost cut even after they were tested on my car. I set 'em at 3.64 on a PWM power supply and i've not had a problem since!!
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