iWire Product FAQ
What is DCCD?
DCCD stands for Driver Controlled Center Differential. Explanations for this system are complex and tend to go about like this:
If we put aside the highly technical specifics (and semantics), the core concept is that a DCCD equipped transmission can adjust the distribution of power between front and rear wheels to allow the car to perform better in any situation. Without a DCCD controller, the differential doesn't have anything to tell it what to do, so it will default to a fixed setting that sends more power to the rear than front.
Why do I need a controller?
Longevity – A lack of electronic input can lead to reduced life for your transmission. The center differential was designed from the factory to utilize these inputs and without them the mechanical parts in the differential must work harder, leading to more wear and tear.
Performance – The DCCDPro will help you corner faster, get through snow/ice/mud easier, and of course, make donuts effortless. It does this by adjusting the center differential to suit the conditions based on inputs like acceleration, braking, and how hard you are turning.
Dyno Tuning – Many dynamometers (dyno) require all 4 wheels to spin at the same rate. As mentioned above, without input, the center differential will default to a rear wheel bias which means the dyno can’t function properly and you will not be able to have your car tuned until the problem is fixed. Not only will you lose the time (many tuners are booked out months in advance) but potentially the cost for the setup time.
Upgrade Over Stock - Even if you already have a car that came from the factory with a DCCD equipped transmission and controller, an aftermarket controller can give you more features. The DCCDPro comes with options to tune the controller to your needs as well as an additional input to utilize Left Foot Braking.
How do I know if my transmission came equipped with DCCD?
Just having a transmission with 6 gears doesn't mean it came with DCCD. Conversely, just because the transmission has 5 gears doesn't preclude the transmission from having DCCD. Take a look at the plug on the top of the transmission and see which style of plug to the right it matches.
NON DCCD Equipped
Which DCCD Controller is right for me?
It all depends on your project so check out our options and get more information on our DCCDPro Products Page!
AVCS Wiring Information
What is AVCS?
AVCS stands for Active Valve Control System. Basically AVCS adjusts the valve position in the engine. By manipulating the valves you effect the air flow through the engine. Optimal air flow leads to more power, and isn't that what we all want?
Why would I install AVCS?
An AVCS Kit is a fantastic upgrade to an 02-05 USDM WRX is swapping in a 01-05 JDM WRX or STi because not only are they more powerful, but they are plug and play with the stock wiring harness. The only difference is that the JDM engines have extra wires to control the Active Valve Control System (AVCS) which is the key to the better performance found with these JDM engines. For this feature to be activated, the ECU needs to communicate with the engine. Choose one of our iWire AVCS kits that are simple to install and will help you get the best performance out of your new upgrade as possible!
Which AVCS Kit is right for me?
iWire Bulkhead AVCS Kit: This kit is designed for use with a complete JDM engine with wiring attached. This kit is also available with plug and play options.
iWire Bulkhead AVCS Kit with Pre Wired Engine Adapters: This kit is the same as our Bulkhead Kit but includes engine plugs that are pre pinned for you making this a nearly Plug and Play option!
iWire Full AVCS Kit: Recommended for those with just an AVCS equipped long block or heads and no matching intake manifold with wiring harness. It includes wiring for both the bulkhead harness and engine harness.
We accept returns on products purchased online for 30 Days after the order date. There is a restocking fee of 15% of the item being returned. Items must be in working condition with no damage to them. If you need to make a return please email us at to make proper arrangements. Buyer is responsible for the return of the item including shipping cost, unless otherwise noted. Once item is received and checked to make sure it is in original condition, iWire will give a refund of the item's purchase value by check.
We do not accept returns on our wiring harnesses. Since they are custom for each person we can not take them back. If for some reason you are having a technical issue please contact Brian at for troubleshooting support.
Issue Placing an Online Order
Thank you for wanting to purchase one of our products! We are so sorry you are having an issue placing your order. The two most common issues come during checkout. If neither of the solutions below applies to you, please email Whitney at for Online Order Support.
Do you ship to countries besides the United States?
Yes, we are happy to ship products anywhere in the world. Shipping times and cost will increase based on distance from the U.S. If you are having any trouble paying as an international customer please email Whitney at and she will assist with taking payment.
How can I enter a Billing Address that is different than my Shipping Address?
Make sure that the "My billing address is the same as my shipping address" box is NOT checked. Once you un-check the box, the billing address fields become available. (See Picture Below)
Having issues with your iWire harness or product?
iWire uses high quality products which is why we offer a Lifetime Warranty on our harnesses and products! Our “Lifetime Warranty” is against defects in materials or workmanship and is intended to cover components only when they are used in the manner for which they were originally designed.
This Lifetime Warranty is void on all products that show evidence of abuse, lack of proper maintenance, improper installation, misapplications, alteration in any way whatsoever from their original design or negligence in the use of iWire products.
Our warranty extends only to the original retail purchaser of the component. If you sell the car with the iWire harness or products still intact we are happy to help the new owner but there may be a fee depending on the service(s) needed.
In the event a problem occurs with an iWire component, please contact us at firstname.lastname@example.org. Please include your invoice or order number in your email. We will then work with you to troubleshoot the problem. If iWire finds the components to be defective, iWire will repair, replace or issue a credit to the customer. Please note that no replacement warranty parts can be shipped until original parts are returned to iWire for inspection