X5 key won't start the car

My X5 (2004 3.0 Diesel) has been off the road for about a year and I have replaced the battery but the it won't start. The key will lock/unlock the doors but nothing when I try to start it. I have only one key and during the time it was off the road my son dropped the key and it fell apart, I have put it back together and like I said it locks/unlocks but nothing when I turn the ignition, no click from the starter motor, nada.

I have researched the forums and I wanted to ask about the 10 second thing re the immobiliser, if I lock the car and then unlock it and try to start it within 10 seconds should this work, so I can at least move the car. secondly do I need to order a new key or is there any other solution.

Many thanks in adavance.

The EWS system might be faulty in that key. Try opening it to check? Might need a new one, unfortunately.

When the key was dropped it could have broken a solder joint for the EWS transponder. That EEPROM must be able to communicate with the EWS control module & DME/ECU. And it also needs the charging coil to operate...and that may have been damaged as well. Looks like you need to do some surgery and go back in....or get another key.