On 17 January 2023, an ATR 72-200 in the final stages of a CAT 2 ILS night approach to East Midlands experienced a significant electrical malfunction which disabled one set of primary flight instruments and triggered multiple system status indication failures. These included false system warnings and radio communications problems. The approach was discontinued, a MAYDAY declared and a successful manually-flown diversion to Birmingham was then made. The cause of the electrical malfunction was found to be a wiring defect which was considered to have probably been caused by the incorrect use of mechanical wire stripping tools during third party maintenance.