Bench Harness Battery Jumper for ECM & TCM

Reliable power is essential for accurate bench-testing of ECMs and TCMs during heavy-duty engine or transmission conversions—connecting directly to a 12V battery source prevents unstable voltage issues that could damage modules or skew diagnostics. Kustom Truck Parts' bench harness battery jumper connects your base bench harness to the battery, delivering a consistent, reliable power supply. 

This jumper is built tough for repeated use in shop environments and pairs seamlessly with our base bench harness. Available in variants like Alligator Clips, Ring Terminals, or an 18V Milwaukee Battery adapter, it's ideal for Caterpillar (ADEM), Cummins (CM), Detroit Diesel (DDEC), or Allison TCM testing in repower projects.

Browse below for battery jumper options that fit your bench setup. Pair with our ECM/TCM jumper harnesses for complete OEM-specific diagnostics. Need help choosing a battery jumper? Contact our team—we're here to support your conversion build.