1999 UK Explorer - beeping !

Hi there,
I have just acquired a 1999 UK model Explorer and I have an annoying problem. On start-up (and at apparently random times whilst driving) it
emits 5 bursts of 5 beeps (the same beep as when you open the door with the key in the ignition).
At first I thought it was a frost warning as it seemed to go off when the temp dropped to 3C (about 40F), but it does it lots of other times too.
Does anyone have any ideas ?
Thanks db
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Check to see that all of the warning indicators prove out at key on... particularly the supplemental restraints light and the ABS light. If either of these warning indicators cannot illuminate, the GEM will sound a chime to indicate that there is a problem.

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Does it continue to beep if you and your front seat passenenger have your seatbelts buckled? Sounds a lot like the belt minder system in operation.
You can download a US Spec Owners Guide From https://www.fleet.ford.com/maintenance/owners_manuals/default.asp .
Ed
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