Fuse MPX-B Parasitic Draw The fuse under the hood in slot # 34 is a MPX-B 10 amp fuse labelled "meters" in the manual. Is the MPX B identified as MPX Multiplex Communication System? Mine keeps blowing out after my battery was drained and the altenator 20amp fuseable link. MPX Multiplex Communication System MPX-B fuse - Ok guys (and girls) i've been having an amp draw problem in my 99' 4runner, it pulls. Total Drain is ~150mA through the DCC Fuse (and at the battery). When you disconnect the MPX B fuse you are effectively cutting some of the power to the body control module, which is responsible for the. General Tech Help - '99 4Runner MPX B fuse blows - Is the MPX B identified as MPX Multiplex Communication System? Mine keeps blowing.