As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AUTOTHROTTLE DISENGAGED DURING DESCENT. PERFORMED AUTOTHROTTLE TO TCQ INTERFACE TEST IAW AMM 22-31-00-710-801-A. TEST FAILED LEFT CHANNEL. REPLACED THE THRUST CONTROL QUADRANT IAW AMM 76-11-01-000-801-A. OPERATIONAL CHECKS GOOD. RETURNED TO SERVICE.