mike_stone wrote:Would that cause the immobiliser light to be on the dash and a beeping noise ?
Not likely.
The signalling you get is a key recognition failure.
And then my best guess is a failing transceiver coil fitted around the lock barrel.
They are prone to have a short service life.
They can be checked with an ohm meter, as obviously the coil should show some sensible ohmic resistance. They disrupt (hi ohmic) on failure.
6160.50 TRANSP.ANTENNA - TRANSPONDER UNTIL RPO No. 08609 (until 05june2000)
Over here my place the pricetag is some £18 exvat