The 3rd generation Subaru Imprea was released in 2007. It addressed most of the security vulnerabilities of the previous generation car, in that all models come with a factory immobiliser, plus the pillar-less windows are gone. There is also a basic alarm on some models.
It’s worth noting that Subaru did not offer an immobiliser on any model until March 2003 and even then this only applied to models sold in New Zealand. More details of which can be found here…
The CAN-BUS system on the Impreza is interesting as locking and unlocking it with the switch on the drivers door generates the same data as a remote lock/unlock. This is a problem for most aftermarket CAN-BUS alarms as they can be tricked into arming/disarming which is also an issue with most Nissan’s and some Mazda’s as explained here…
The good news is that the Cobra AK4615 has this covered so has a switch inhibit built in to the alarm to prevent the vulnerability. Nearly every other brand of alarm I’ve looked at is compromised by this so be warned!
The Cobra AK4615 in action on the Impreza:
Some photos of the details:
I recommend a ADR card for models with the smart key and push to start to protect against key cloning.
Changing the Remote Battery on the Smart Key
Remove the key blade section of the remote, then use a small flat blade screw driver and prize open as shown in the photo below.
Inside you’ll find a CR1632 battery.
Gen 2 Impreza Security
If you have a Gen 2 Impreza made after March 2003 then a Cobra AK4615 can be made to work in PLIP configuration from the factory remote. If it is a Jap import or an older model including the Gen 1 then I’d suggest an insurance standard immobiliser as a minimum level of protection. If getting an alarm then think about getting one with Ultrasonic Sensors. If its a WRX then I highly recommend the Cobra AK4138.