The three leads to find first
On the Haltech Elite premium universal harnesses, power and ground come in through these flying leads:
| Lead color | Job | Details |
|---|---|---|
| Black | Battery ground | Black battery ground |
| Red/Green, Red, Red/White | Battery supply, 12V | Battery supply leads |
| Pink | Ignition switch, 12V | Ignition switch feed |
Each linked page goes through where that lead should connect. Wire all three before anything else. A lot of "ECU won't connect" and "engine won't start" problems trace back to one of these, and a poor ground in particular causes odd sensor readings that are hard to chase down later.
Our ECU grounding guide covers the ground side in more detail. Buying a harness? The Elite 1500 premium harness kit and Elite 2500 premium harness kit both use this layout.
