As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
REF TC 78273000 ENGINE 1 SHOWS THE SHORT TERM FAULT. NUMBER 75-20421. HMU VBV CONT CURR OUT OR RANGE. GROUNDED - YES. CONFIRMED FAULT ACTIVE 6 OF 10 FLIGHT LEGS. PERFORMED B737-800 FIM 75-32 TASK 804. FOUND SLIGHT RESISTANCE FLUCTUATION WHEN CABLE MANIPULATED AT DP0606. AS PRECAUTION, REMOVED AND REPLACED J6 HARNESS ON #1 ENGINE. OP CHECK GOOD. ERASED EEC FAULT HISTORY FOR EASIER TRACKING OF 75-20421 IN THE FUTURE.