Holley 554-165 EFI CAN Input/Output Module Kit w/ Harness – For HP, Dominator & Terminator X/X Max
Holley’s 554-165 CAN I/O Module kit is the easy way to add more inputs and outputs to your Holley EFI system. Designed to plug into HP, Dominator, Terminator X, and Terminator X Max via CAN, it adds eight inputs and eight ground/PWM outputs so you can control more accessories (fans, pumps, nitrous, boost, lights, etc.) and log more sensor data without changing ECUs. Includes a pre-terminated CAN harness and flying leads to simplify wiring.
Brand: Holley EFI
Part Number: 554-165
Product Type: CAN Input/Output expansion module kit w/ harness
Compatibility: Holley HP, Dominator, Terminator X, Terminator X Max ECUs (via CAN bus)
Inputs: 8 multi-purpose inputs (12V switch, ground, 0–5V analog, thermistor) for items like fuel/oil/nitrous pressure, coolant temp, brake switch, toggle switches, etc.
Outputs: 8 ground / PWM outputs for fan control, fuel pump control, nitrous/boost-related devices, relays, and other PWM-controlled accessories
Broadcast Rate: Adjustable per channel from 0–100 Hz over CAN
Included Harness: Pre-terminated CAN harness plus flying leads to tie into your existing Holley EFI installation quickly
Use Case: Ideal when you’ve maxed out the native I/O on HP or Terminator X (4 in / 4 out) or want even more flexibility on Dominator and Terminator X Max systems
Software Requirements: HP/Dominator requires Holley EFI V6 Build 200+; Terminator X requires V2 Build 51+
