MikiD

Can anyone help? My X5 will start first time from cold even after over night frost or left for two weeks with no problems. If I drive 20 miles or 120 miles and then stop for 2 minutes or 20 minutes the car turns over with plenty of battery but will not start. Of course after trying to start the car six/seven times, battery starts to run down so have to stop trying. If however, after driving 20/120 miles I leave the car for over an hour it seems to start OK. It can be started with booster cables although the battery does not seem to be the problem, I have checked for battery leakage and had the alternator checked, all OK. I don't know if the following is connected but I have intermittent faults with parking sensors and computer/sat nav screen not coming on. Car has done 80,000 miles. Have you any suggestions as to what the fault is and how it can be rectified.