TTMA 7-way plug, the trailer shall be equipped with the following 12-way military intervehicle
a. Military 12-Contact Plug MS75020-1.
b. Military Intervehicular Cable MIL-C-13486 and MIL-C-13486/12.
The military plug and cable assembly shall be the same length as the TTMA plug and cable
assembly and both shall be labeled with identification plates for 24-volts and 12 volts
respectively, negative ground. The military 24-volt intervehicular cable shall be routed into a
weatherproof stud and nut type junction box, equipped with SAE J553 circuit breakers,
protecting live circuits B, E, and J of the military service lamp portion. As required for the
TTMA plug and cable, see VMRS 34-003-036, the military plug and cable assembly wire ends
shall terminate in spade type connectors of TMC-ATA RP-112. The assembly shall be
permanetly fastened to the trailer by strain relief clamp and the terminal connectors to prevent
detachment and loss of the plug and cable. All unused leads of the cable shall be insulated and
sealed watertight. The military 24-volt circuits shall be connected through replaceable solid state
devices or resistors, for live circuits, and to the trailer frame, for ground circuits, in accordance
with table IV. The resistors shall be exposed to ambient air for cooling and shall be protected
from damage, road debris, and accidental burning of operational personnel.
TABLE IV. Military-Commercial Connections.
Ser. Left Turn & Stop
Ser. Tail & Marker
& Connect to
Ser. Right Turn & Stop
Aux. Power (Hot)
Ground to Frame
With the military system installed, the TTMA marker circuits, color coded BLK (2) and
BRN (6), shall be electrically insolated from each other, thus preventing 12-volt current
cross-over when operated by commercial trucks through the 12-volt TTMA plug. Replaceable
diodes may be used, having a minimum amperage of 150 percent of the current demand of the
running lamps served. Military circuits letter coded B and J on the tactical trucks are passenger