What was found
ON PREFLIGHT, FO COURSE SELECTOR COURSE WILL NOT CHANGE WITH KNOB MOVEMENT, KNOB CLICKS WHEN TURNING. GROUNDED - YES. RMVD & RPLCD DFCS MODE CONT PNL PER B737-800 AMM 22-11-34, ORIGINAL PROB FIXED BUT LAND VERIFY TEST FAILS WITH "ELEV POS FAIL MSG 22-11126, REF B737-800 FIM 22-11 TASK 812, DFCS #30 TEST PASSED, PERFORMED SUCCESSFUL LAND VERIFY TEST & ALL REQUIRE TEST PASSED, AMM 22-11-00-700-801.