If the door lock is ok, then change the main module. We stock it at £59.88 + £6 postage (exchange). This is ready programmed for your model number. To order, go to our website at www.emwelec.co.uk and put WT640 in the search box or call us on 01159652118. You will still have the option of returning the module within 14 days for a refund (less our handling of £12) if it does not sort out the problem. Tony EMW Electronics
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