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    Sale!

    Holley EFI Benchtop Harness, ECU Testing & Dash Configuration | 558-127

    Vendor: Holley EFI
    Part Number: 558-127
    Save $32
    Sale Price $249.95 Regular Price $281.95

    Available to order. In-stock orders typically ship in 1 to 2 business days.

    Not sure it fits your vehicle?
    Email sales@berryperformancesales.com with your year, make, model and engine, and we'll help you check fitment before you order.
    Fast Fulfillment: In-stock orders typically ship within 1 to 2 business days.
    Free Shipping on Orders Over $99 | Excludes freight shipments
    International Shipping Available: email sales@berryperformancesales.com for a quote.
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    This benchtop harness is designed for testing and setup of Holley HP, Dominator, Terminator X, Terminator X Max, and Sniper ECUs, as well as 7" digital dashes, away from the vehicle. It's suited to ECU diagnostics, firmware updates, or pre-configuring dash layouts on a test bench.

    Specifications:

    • Terminated Connectors for CAN, Crank, Cam, TPS, Input #1, P1A, and Main Power
    • Includes Sniper EFI Connectors for a Sniper Main Harness
    • Built-In Power Switch for Quick Bench Setup
    • Color: Black
    • Part Number: 558-127

    Power and ground flying leads must be connected to a battery or power supply (not included).

    FAQ

    What ECUs does this harness support?

    It's designed for benchtop testing and setup of HP, Dominator, Terminator X, Terminator X Max, and Sniper ECUs, plus 7" dashes.

    What is it useful for?

    ECU diagnostics that don't require a running engine, firmware updates, and pre-configuring 7" dash layouts.

    Does it include a power supply?

    No. It includes a power switch, but power and ground flying leads must be connected to a battery or power supply separately.

    What sensor inputs are pre-terminated?

    CAN, Crank, Cam, TPS, Input #1, P1A, and Main Power, plus Sniper EFI connectors for a Sniper main harness.

    Shipping Policy
    • Free shipping on orders over $99 (excludes freight shipments).
    • In-stock orders typically ship within 1 to 2 business days. Weekend and holiday orders are processed the next business day.
    • Orders ship from Defiance, Ohio and a nationwide network of warehouses and manufacturers.
    • Items showing an ETA are not in stock yet. ETAs come from the manufacturer and can change.
    • No P.O. Boxes. International orders need a shipping quote, so email us first.

    Read the full Shipping Policy

    Return Policy
    • 30-day return window from the ship date. Returns must be approved first; email sales@berryperformancesales.com with your order number.
    • Items must be unused, complete and in the original packaging.
    • A 20% restocking fee applies, and return shipping is paid by the buyer.
    • Not returnable: installed or modified parts, opened or used programmers and tuners, custom orders, Open Box, and Clearance or Final Sale items.
    • Damaged, defective or incorrect items must be reported within 48 hours of delivery with photos.

    Read the full Return Policy

    Disclaimer

    All products are sold for off-road use only unless otherwise specified. Buyer assumes all responsibility for installation and operation. Seller is not liable for any incidental, indirect, or consequential damages — including engine failure, labor costs, or vehicle downtime — resulting from the use of any product sold.

    By making a purchase from Berry Performance Sales, you acknowledge and agree to abide by the terms and conditions of these Policies.

    For any questions or concerns, please contact us — we’re always happy to help.

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