VOLTAGE TEST   (1)  Remove four screws from RH door marker         light base. Do not let wires slip through hole  into cab structure.  If wires slip into cab structure, vehicle will need further disassembly to retrieve wires. NOTE CAUTION Remove rings, bracelets, watches, necklaces, and any other jewelry before working around vehicle.  Jewelry can catch on equipment and cause injury or short across electrical circuits and cause severe burns or electrical shock. WARNING Use care when testing electrical connectors. Do not damage connector pins or sockets with multimeter probes.  Failure to comply may result in damage to equipment.                             NOTE Inspect connector pins/sockets for damage, corrosion, and serviceability.  Check that connector pins are not pushed back and are capable of making good contact.   (2)  Remove nut, lockwasher, terminal lug TL131,         and lockwasher from RH door marker light         base.  Discard lockwashers.   (3)  Extend base and disconnect connector P131         from marker light connector.   (4)  Remove gasket from RH door marker light         base.  Discard gasket.   (5)  Set multimeter to volts DC.   (6)  Connect positive (+) probe of multimeter         to connector P131 socket.   (7)  Connect negative (-) probe of multimeter         to ground.   (8)  Position main light switch to SER DRIVE         (TM 9-2320-365-10) and note reading on         multimeter.   (9)  If 12 VDC is not present, repair wire 1947         from connector P131 socket to splice         E22 (para 2-40) or replace RH door and cab         marker lights cable assembly (para 7-57). (10)  Position main light switch to OFF         (TM 9-2320-365-10). Change 1          2-556.3 TM 9-2320-365-20-1