AN/VIC 3: Power Cable Sparks Problems

Although the AN/VIC-3, vehicle intercom system (VIS), has been in the field a long time, there’s an ongoing issue with the power cable. If not fixed, it may cause injury and equipment damage.

The problem is the power cable can short against various items when not connected to the master control station (MCS) part of the VIS.

The MCS is powered from the MT-6352A mounting base, via the output connector on the far right.

If power is connected to the mount, the cable has 24 VDC on its female connectors.

The two pins themselves protrude from the cable end.

If placed on a flat, conducting surface, this connector sparks and melts the female connectors, rendering the VIS unusable.

Another problem happens when connecting the power cable to the MCS while the power source is turned on. Once the protruding pins on the power cable get close enough to the power connector of the MCS, it will spark again, possibly damaging the cable or the pins of the power connector on the MCS.

It’s good practice to always leave the power connector to the MCS connected. However, if replacing a faulty MCS, the main power to the vehicle should be turned off prior to removing the MCS power cable.

In HMMWV variants, the MT-6352A gets its power directly from the battery. So the best thing to do is remove the input power cable from the MT-6352 prior to removing or attaching the power cable for the MCS.