TC reported ATP Safety System Fault illuminated after a lightning strike. TC later reported BCU faul t indication at rear DT. TC reported train undershoot at CCKNB and BGB NB. TC ATPM to Headwall.TC shut down opened up ERS-15 ~~~~~ L3 3566 Tacho 3 wire 3038 & 8039 shorted to GND. Refer to SIG L for investigation.  Chan SW/Hanafi. 13/04/2020. Event recorder fault at 3566. L3 3566 event recorder swopped to 3565 but fault still remained at 3566  Chan GF. 13/04/20. L3 3566 checked earth brushes & cables - OK.  Chan SW/Hanafi. 14/04/2020. L3 3566 TIMS unit swopped to 3565, fault remained. Swopped CIF2 card to 3565 & fault transferred. Replaced CIF2 card at 3565 - Done. Function test - OK. Event recorder fault cleared. 3565 CIF2 Card S/N : OLD : CY51844PZ. NEW : DS43635PZ.  Chan GF/Alcus. 14/04/2020. L3 565/566 ER D/L & found FC 322/323. Checked wheel slip/slide detected from event log. Found 3566 all brake shoes badly worn - replaced with new. Found 3566 A4/B4 wheels having wheel flat (50mm x 60mm). MOC: Depot found 3566 BCU faulty causing stuck brake. BCU replaced & brake functional test ok. Checked & found Tacho 3 one wire shorted to GND. To have joint inspection with SIG L staff. 3566 BCU S/N : OLD : 1826102. NEW : 1809057.  Goh AT/Chan GF/Alan. 09/04/2020.