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Holley EFI CAN Input/Output Module - Without Harness

Part # 554-166

Adds Up To (8) Inputs and Outputs

Holley EFI CAN Input/Output Module - Without Harness

Estimated Ship Date: 08/11/2025
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$399.95
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5

Emissions

This part is legal for sale or use on Emissions Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations.

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The Holley EFI CAN Input/Output Module can be added to Holley EFI HP, Dominator, Terminator X and Terminator X Max EFI installations. This CAN module will add (8) inputs and (8) outputs to the system which can be used to control additional accessories or provide critical sensor inputs. This module is perfect for anyone wanting to enhance the capabilities of their current ECU and have already tapped out their ECU's Input/Output channels. Please refer to 554-165 for full kit.

Features:

  • Perfect for anyone wanting their Holley EFI ECU to control more functions or monitor more data channels
  • HP and Terminator X EFI installations with only (4) inputs and (4) outputs can now add more functionality to their EFI system
  • Expand Dominator ECU’s Input / Output control with (8) additional inputs and outputs
  • Inputs can be used for things such as:
  • -Switch 12V Toggle Switches - can be configured for external mechanical relays or setup as digital switches via a Holley EFI dash
  • -Ground input for brake pedal switch
  • -5v analog inputs for sensors like fuel pressure, oil pressure, or nitrous bottle pressure
  • -Thermistor inputs for Coolant temperature sensors
  • Outputs can be used for things such as:
  • -Switch Low (Ground) - for relay control or activation
  • -Switch Low PWM (Ground) - PWM Fan Control – PWM Fuel Pump Control - or other PWM- controlled devices

About Holley EFI

Find standalone EFI for LS, Coyote, Hemi and more at Holley.com. From engine swapping to managing up to 4000 horsepower, we have a solution for every project!

Brand Holley EFI
CategoryEngine
Connector GenderFemale
Emission Code5
Grade TypePerformance
Mounting Hardware IncludedNo
Mounting Hole Quantity4
Part TypeEngine Control Module (ECM)
Product TypeCAN Input Output Module
Sub CategoryControl Modules
Terminal GenderFemale
UPC090127104118
Part Number554-166
5

This part is legal for sale or use on Emissions Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations.
Dominator and HP requires V6 software version Build 200 and higher. Terminator X requires V2 software Build 51 and higher.

*Free Shipping and Handling only offered to the contiguous US on orders over $149, excludes clearance parts and oversized packages.

Some parts are not legal for use in California or other states with similar regulations.