Probably main module in the back of the machine. 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 WF541 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
www.emwelec.co.uk, November 2013
