I searched this one but didn't find the exact same issue.
03 S40, 42K.
Lately when I start the car, the immobilizer light comes on and stays on.
The car starts fine and is driveable. I end up shutting the car off, and clicking the unlock mutiplele times. Eventually y afetr a few tries it starts with th light out.
Will I damage the car driving with the immobilizer light on?
What is an easy way to fix this. I keep meaning to try my other key and see if that helps.

 

Try your other key.