In this blog post we go over iDCCD control methods and which one is best for your Subaru project.
One of the advantages of the iWire iDCCD Controller is that you aren’t locked into one way of controlling your DCCD. Depending on your Subaru build, you may want the factory-style experience of an OEM DCCD switch, the flexibility of the iWire app, or a simplified custom switch setup. So which one should you use?
The best choice usually comes down to how you use the car, what interior you have, and how much control you want at your fingertips.
The Three Ways to Control iDCCD
With an iDCCD setup, there are three main control approaches:
- OEM Subaru DCCD controls for a factory-style installation (OEM Roller Switch, Auto/Manual Button, or SI-Drive Panel).
- The iWire app for tuning and control from your phone.
- Custom switches for swaps, race cars, or simplified interiors.
All three share the same goal: giving you control over how the center differential behaves. The difference is how you interact with it.
Option 1: OEM DCCD Switch
Best For: Street cars, OEM+ builds, and Subaru interiors where you want everything to look factory.
If your goal is to make the car feel like Subaru installed the DCCD system from the factory, an OEM switch setup is usually the best fit. In older cars, you can use the coin slots in the center console for the switch and button, or do a full center console swap with the SI-Drive Panel in newer cars.
Why Choose the OEM Switch?
The biggest advantage is simplicity. Once everything is configured, you can operate the DCCD without pulling out your phone. The controls are familiar, easy to reach, and blend into the interior. For a street-driven WRX, STI swap, or clean restoration-style build, this is often the most natural setup.
Option 2: Control iDCCD With the App
Best For: Drivers who want access to live data readouts or don't want to spend the time or money on OEM switches.
The iWire app gives you a much deeper look at what the controller is doing. Rather than simply changing DCCD output, the app lets you configure how the system responds and choose settings based on how you drive the car.
You can set up the car for different situations such as:
Street
A balanced setup for normal driving.
Track
Settings focused on performance driving and quicker vehicle response.
Off-Road
Useful for loose surfaces or builds where maximum traction is the priority.
You can also fine-tune the handling response within those profiles with the slider on the home page.
Why Choose the App?
The biggest benefit is flexibility. You aren't limited by the switches installed in the car. If you change the vehicle or want to experiment with a different DCCD setup, you can adjust the controller without rewiring the car. The app is also the easiest way to access more advanced iDCCD settings.
Once you've configured the car the way you like, you don't necessarily need to keep your phone open every time you drive.
Option 3: Custom DCCD Switches
Best For: Race cars, custom dashboards, older Subarus, and cars without an OEM DCCD interior.
Sometimes an OEM Subaru switch just doesn't make sense. Maybe you're putting an STI six-speed into an older Impreza. Maybe the car has an aftermarket dash. Maybe you've removed most of the factory interior. Or maybe you simply want a large, easy-to-reach switch for track use. That's where custom switch inputs become useful.
iDCCD can work with external switch inputs, allowing builders to create a control layout that fits the car rather than trying to make the car fit an OEM switch.
Keep in mind that custom switches would need to be wired in with inputs similar to the SI-Drive Panel.
Auto/Manual - Treat the Auto/Manual switch as a ground-triggered command. Each valid switch activation should toggle the controller between:
Auto → Manual → Auto
The switch does not need to directly carry or provide a mode voltage. The controller maintains the current operating mode internally and changes modes when it detects the input being pulled to ground.
DCCD Plus (+) - The Plus (+) switch is a ground-triggered momentary input. When the Plus input is pulled to ground, the controller should increase the commanded DCCD setting by one step. Example: 50% to 60%
A press-and-release should normally equal one adjustment; holding it will continue moving the input while you hold.
DCCD Minus (-) - The Minus (–) switch operates the same way. When the Minus input is pulled to ground, the controller should decrease the commanded DCCD setting by one step. Example: 60% to 50%
Note – we are working on CANbus integration for the switches, so in the near future we’ll be able to offer CAN inputs to change the iDCCD.
Why Choose Custom Controls?
Freedom. You can position the switches wherever they make the most sense for the driver. For a dedicated track car, that might mean putting the controls next to the shifter. For a GC or older Subaru swap, it might mean using a simple switch instead of retrofitting newer Subaru center-console components.
Custom switches are also useful when integrating iDCCD into a larger custom electrical or motorsport control system. Please keep in mind that custom switches require custom wiring to the iDCCD Controller.
Which Setup Is Best for Me?
Street Car
For most street-driven builds, we prefer either OEM controls or a combination of OEM controls and the app. The OEM switch gives you quick access while driving, while the app handles the deeper configuration.
That combination gives you the factory-style driving experience without giving up the flexibility of a modern controller. It's particularly useful for OEM+ Subaru builds where you want the DCCD system to feel like it belongs in the car.
Track Car
Track builds depend heavily on the rest of the interior. If the factory interior is still intact, the OEM switch can work extremely well. If the vehicle has a custom dash, switch panel, or stripped interior, custom controls may make more sense.
You can then use the app during setup to configure DCCD behavior before going on track. That means the driver can have simple physical controls while driving without needing to navigate through a phone.
What If I Want to Upgrade the Car Later?
This is another reason we generally recommend thinking beyond just the switch. The switch is only the interface. The iDCCD controller is the system actually managing the center differential.
As your build changes, the way you interact with it can change too. You might start with app control while finishing a swap, then add OEM controls later. Or you might begin with an OEM-style street car and eventually convert it into a track car with a dedicated switch panel.
iDCCD is designed to be updated, so if you change your control type, all you have to do is tell the controller, and you’re good to go!
