As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON PUSHBACK, NR 1 ENGINE START VALVE OPENED UNCOMMANDED "START VALVE OPEN" LIGHT ILLUMINATED. GROUNDED-YES. PERFORMED B737-800 FIM 80-07 TASK 809, FOUND CONTINUITY FROM PIN (4) AND (5) OF START VALVE THIS INDICATES REPLACEMENT OF THE START VALVE. REMOVED AND REPLACED NR 1 ENGINE START VALVE, PER B737-800 AMM 80-11-03-401. LEAK TEST PERFORMED, PER AMM 71-00-00-700-809-F00. NO LEAKS NOTED.