As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WITH #1 START SWITCH IN GROUND POSITION NO N2 ROTATION NOTED. GROUNDED - YES. CYCLED #1 START CONTROL VALVE. PERFORMED NORMAL START - OPS GOOD. REF B737-800 AMM 71-00-00. REMOVED AND REPLACED #1 ENGINE START VALVE PER AMM 80-11-03. OPS CHECK NORMAL. PERFORMED PNEUMATIC LEAK CHECK PER AMM 71-00-00 TEST 1. NO LEAKS DETECTED. GROUND VERIFICATION CHECK GOOD.