How do you wire the A/C system when running Holley Terminator X EFI on an LS swap?

Here is what the documentation says. Each point links to its source; details depend on your exact computer, harness and transmission.

• Holley Terminator X; GM LS: Holley Terminator X provides an A/C Kick input on ECU pin A12 (connector pin A, white/blue) and an A/C Shutdown output on ECU pin B10 (connector pin G, gray/black) that deactivates the clutch at a configured throttle position; the kick input is a ground-activated signal. (Holley (via CARiD mirror))
• Holley Terminator X; GM LS: Holley Terminator X has an IAC Kick feature that automatically adds IAC steps so the engine does not experience a momentary drop in idle when the A/C compressor kicks on. (Holley (via CARiD mirror))
• Holley Terminator X; GM LS: Holley Terminator X fan outputs are Fan 1 on ECU pin B12 (connector E, gray/yellow) and Fan 2 on ECU pin B11 (connector F, gray/red); these are ground outputs that trigger fan relays and must never be connected directly to the fan motor. (Holley (via CARiD mirror))
• Holley Terminator X; GM LS: Holley Terminator X provides a fuel pump relay output on J1A connector pin A2 that supplies +12 volts at up to 10 amps maximum. (Holley (via CARiD mirror))
• Sources differ: This +12V high-side output is Holley-specific; GM P01/0411 factory pinouts list the fuel pump relay control as a low-side (ground-switched) driver, so polarity must not be assumed across controllers.
• Holley Terminator X; GM LS: The Current Performance Holley Terminator A/C integration module operates the A/C compressor clutch, interfaces with the Holley ECU for A/C shutdown and IAC kick, and signals the ECU to request electric fan operation while the A/C runs; it includes binary pressure-switch leads, an A/C relay, and a 10-amp inline fuse. (Current Performance Wiring)
• Holley Terminator; GM LS: Holley Terminator systems provide outputs for up to two electric cooling fans plus an A/C shutdown output that deactivates the A/C at higher throttle settings. (MotorTrend)

Confirm against the instructions for your exact parts before wiring. More: Other wiring in our tuning guide.