ShieldPer bend Buff and Purpure, a motor truck wheel Proper a motor truck wheel Proper (aluminum hub cap, black hub, and rim, yellow spokes, gray tire), within a bordure indented compony Or and Crimson.
CrestFrom a wreath Or and Gules (Crimson), a triangle Azure fimbriated Or charged in chief with an eight-rayed sun above two bolo knives saltirewise overall all of the last.
MottoFIRST IN MAINTENANCE.
ShieldPurple, buff and the wheel reflect the original organization, the 3rd Mortar Repair Battalion. The indented crimson and yellow border denotes the unit's descent from Ordnance. The indentations represent the speed with which missions are accomplished.
CrestThe crossed bolo knives represent campaign honors earned in Luzon and New Guinea by the predecessor Battalion during World War II. The golden sunburst on the blue triangle is adapted from the flag of the Philippines and denotes the award of the Philippine Presidential Unit Citation to the former unit.
The coat of arms was originally approved for the 189th Ordnance Heavy Maintenance Battalion on 18 February 1943. It was rescinded on 22 April 1977. The coat of arms was reinstated and redesignated for the 189th Support Battalion and amended to add a crest effective 16 September 1993.