Many thanks for your reply Greydog Dave, as always it is much appreciated and proves someone cares. It is true that the soldered batteries appear in the Haynes Manual but they are not in my instrument cluster. My auto electrician friend wonders if the subsequent model didn't appear in any manual. The VIN number is WBAHC22010BK95873 The Haynes Manual we've used is BMW 3&5 Series 1981 to 1991 ( up to J registration ) page 12 *5 Look forward to your reply