I have an immobiliser related starting   problem on my 2005 legacy estate.

If you press the key button , the doors unlock as normal.

Get in, within 30 seconds, and turn the key, all the indicator lights come on, but the starter doesn't  energise.

Press the button on the key, after 30 seconds, still nothing.

If you unlock the car, spend 10 minutes loading up, then get in, turn
the key and press the button, it starts first time as it should.

There is nothing wrong with the starter, by the way.

A couple of times, I have opened the drivers door after not being
able to start the engine, then pressed the button, and the engine
started.

According to the operators handbook, which leaves a lot to be desired as it covers too many variants, there should be a keypad

inside the car to enter a code if the alarm system goes wrong.

I can't find a keypad on my car.

I wonder if it is possible to alter the system to allow the engine to
start anytime after entering the car. The 30 second rule is a waste of
time . can't see the point of it.

I realise that Subaru's have a different spec Stateside, but I hope that someone can help with this .

Thanks

OK, I am told all UK cars are fitted with an alarm Keypad, it's just that neither the Subaru operators manual nor the one for the alarm system tells you where it is.  Sneaky.

It is fitted inside the interior fuse box cover.

The keypad is no help with this problem however, as the system arms and disarms normally with the key.

I also now know that the 30 seconds allowed to start the car after entering, and disarming the system is part of the system and cast in stone.