TM 10-3930-675-20-1 0047 00-8 TOPHANDLER TWISTLOCKS AND FORKLIFT SENSOR TROUBLESHOOTING - CONTINUED 0047 00 Table 5. Error Code 246 - Tophandler Twistlock Unlocking Circuit Failure Troubleshooting Procedures. MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION Error    Code    246    -    Tophandler    Twistlock Unlocking Circuit Failure 1.  Check wires and cables from tophandler   control  valve  to boom for obvious damage. Repair or replace damaged wires (WP 0111 00). 2.  Disconnect electrical connector 6039 from tophandler twistlock unlocking    solenoid.    Place ignition switch to ON position and perform voltage check. If 20-25V is present at connector 6039, replace twistlock unlocking   solenoid   (WP   0169 00). 3.  Disconnect  connector  X189 from tophandler junction box at end of boom. Place ignition switch   to   ON  position   and perform voltage check between connector X189 pin J and pin K. a.  If 20-25V is present, check continuity    between    con- nector   X189   pin   J   and connector  6039  pin  1  and between   connector   X189 pin K and connector 6039 pin   2.   Check   continuity between    connector    6039 pin   1   and   pin   2   and   to chassis.   Check   continuity between   connector   X189 pin    K    and    ECU    (791) connector 2 pin 8. a. If  continuity  is  not  present, repair  or  replace  connectors (WP 0111 00). b. If    wiring    harness    requires replacement, notify DS Maintenance. b.  If  voltage  is  not  present, enter   “DIAG   ATTACH- MENT  6  (16)”  menu  and check voltage of UNLOCKED OUTPUT. Voltage  should  be  present with   joystick   lock/unlock and  override  switch  1005 activated (press switch twice for lock and unlock). a. If    voltage    is    not    present, replace ECU (791) (WP 0076 00). b. If  voltage  is  present,  notify SRA. DIAG TOP LIFT   6(16) TW-LOCK OUTPUT INPUT UNLOCKED 0.00V 0Ma LOCKED   0.00V 0mA