What was found
STAB OUT OF TRIM LIGHT CAME ON AT FL320. RAN QRC/QRH. AUTOPILOT NOT TRIMMING. ELECTRIC TRIM WORKED NORMALLY. ACFT GROUNDED. VERBAL FROM CREW AUTOPILOT B IN CMD, DFCS FFR SHOWS NO PREVIOUS FLIGHT FAULT FOR CH "A", CH "B" SHOWS MESSAGE 22-11830 FOR PREVIOUS FLIGHT. CURRENT STATUS TEST PASSED, HOWEVER, SPEED TRIM SYSTEM FAIL 14.32, MESSAGE 22-11163, COL SW MODULE M1201, FWD SW FOR FCC-B. RANG OUT M1201 F/O COLUMN SWITCHING MODULE, IAW WDM 22-13-11 AND SSM 22-13-11. S6 FWD COLUMN SWITCH VERIFIED HIGH RESISTANCE IN GROUND POSITION. CONFIRMED F/O MODULE BAD. REPLACED F/O COLUMN SW MODULE M1201. OPS NORMAL, IAW AMM 27-41-51 & FIM TASK 22-13 TASK 808. ACCOMPLISHED LAND VERIFY BITE GROUP 49 & HGS SYSTEMS TEST, IAW LWMP CHECKLIST AMM 22-00-01 AND SMM 34-36-00. ALL TEST PASS.