The Type R didn’t have remote central locking, and I felt like doing a bit of tinkering. And so a plan was born.

I did some reading, and while you can find the central locking control unit (H7110AS011), putting together the entire system: control unit, actuators, remotes, and wiring harness seems impossible, or at least impossible without access to a complete donor car. So I settled on something readily available: Modemix central locking kit. The unit is reasonably well put together: a fuse on the power supply, a split wire for the indicators, not that bad.

The only things I changed were securing the PCB inside the housing a little better, as it was rattling around slightly, and taping the case shut. Somehow, I didn’t quite trust the clips to hold.

There are quite a few kits to choose from. I went with Modemix because the fob supplied with it looks the most like something from the 1990s or 2000s. All the others tried to look more modern and, frankly, seemed rather tacky.

The device offers various options for controlling the actuators. I need the +/- one. This means soldering the orange to the orange-and-black wire, and the yellow to the yellow-and-black wire. I also removed the green and blue wires (for closing the windows and opening the boot).

The instruction manual included in the package has been photocopied a billion times and looks like an artefact discovered by archaeologists at an excavation site, so I took the liberty of redrawing it myself.

This is the plug after the modifications.

I bought the actuators separately. There are several versions available, depending on their pulling force: 4 or 8 kg, and their function: master or slave. A master actuator can send a signal to the other actuators (the slaves) when the key is turned. My control unit doesn’t support master/slave signals, and since I was set on using this particular fob, I ended up with two 4 kg slave actuators.

Armed with the prepared control unit and a pair of actuators, I got started with the installation. I tapped into the radio wiring harness for power and used a multimeter to identify the indicator wires at the hazards switch.

All that remained was to run an additional wiring harness to the doors and install the actuators.

Here’s everything installed. The little cube with three screws is the connector joining the actuator rod to the original door lock linkage; the actuator itself sits directly underneath it. When connecting the wires from the control unit, you need to make sure the polarity is correct so that the lock and unlock buttons on the fob work as intended.

And here’s a little surprise: it turns out the Type R did actually have central locking at some point. On the passenger side (the European passenger side, which would originally have been the driver’s side in Japan), someone had fitted an aftermarket actuator almost identical to the one I’d just bought. On the driver’s side (the Japanese passenger side), I found a factory-fitted actuator.

Unfortunately, the blue arm is broken. I can hear the motor running, but the arm doesn’t turn. I’m planning to strip this car down at some point, so perhaps I’ll rework the central locking then to make use of the original wiring harness.

I mounted the keyless entry module to the dashboard support beam bracket, behind the radio.

And now for the most important question: does it actually work?

It sure does.

• Impreza
• Gc8
• Type-R