Spanner on dash wont start please help

[alshel]

Hi all i have a annoying problem, sometimes when i go to start my car it wont start an on the display there is a spanner in the past when this as happened after 5mins or so it starts,the last 2 times its bin longer this morning car started i stopped at shop when i got back in it wouldnt start n the annoying spanner was there i went back after 2 hours and still the spanner.i went back after work at 7 and after about 20 trys it just started it can go roughly a month or so then it does it again.please can any 1 help or had the same problem thankyou.

[Big Dave]

Sounds like an immobiliser related fault.

Have you got a spare key you can try?

Ultimately though, you need the fault code(s) read out to establish what's wrong.