As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WITH APU BLEED SW ON, ONLY SHOWING 10 PSI. APU BLEED VALVE MANUALLY CLOSED, BREAKERS Q22 & P11 OPEN. CHECKED OPERATION OF BLEED VLV PER MM. OPERATION GOOD NEVER HUNG UP RE-INSTALLED CONN D3576. HOOKED TESTER UP FOUND SV TM VOLT OUT OF TOL. REPLACED SURGE VALVE PER MM.