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SKU:
NLT1C00291
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12-Way LS Swap Fuse Block and Relay Harness Kit with OBD-II
$89.99
In Stock
$89.99
Sale price
$89.99
Regular price
This universal LS-swap electrical kit includes a 12-way fuse block, six fuses, two relays, an OBD-II diagnostic port, and harness tape for compatible 1993-2015 GM V8 harness rework.
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Compatible Models
We do our best to list all compatible models. Although this may be the part you need, your exact model may not appear below.
Compatible equipment / model
- 1993-2015 GM V8 drive-by-cable harness conversions
- 1993-2015 GM V8 drive-by-wire harness conversions
- Compatible LT1, LS1, LS2, LS6, LR4, LM7, LQ4, LQ9, and related 4.8L-7.0L swaps
Product Overview
A stripped factory harness can run an LS engine reliably, but the conversion still needs clean fused power, an ignition relay, a fuel-pump relay, and a diagnostic connector. This kit gathers those circuits into one labeled block for builders modifying a matching drive-by-cable or drive-by-wire loom.
It is not a complete standalone engine harness and does not remove vehicle anti-theft, tune the ECU, or identify every pin. Successful use requires the correct factory diagrams, ECU programming, grounding, wire sizing, fuse values, and relay logic for the exact engine and controller.
Key Features & Performance
- 12-way fuse block with labeled cover
- Six fuses and two relays included
- Separate relay circuits for ignition power and fuel pump
- OBD-II diagnostic connector supports compatible ECU communication
- Made for custom rework of compatible GM V8 harnesses
Common Uses
- Building a clean fused power center for an LS swap
- Adding fuel-pump and ignition relays to a modified factory loom
- Retaining an accessible OBD-II diagnostic connection
Technical Specifications
- Product Type: Engine-swap fuse and relay block kit
- Fuse Block: 12 way
- Included Fuses: 6
- Included Relays: 2
- Diagnostic Port: OBD-II / DLC
- Fitment: Universal custom wiring
Installation & Fitment
- Use factory ECU pinouts for the exact service number
- Provide clean engine, chassis, and battery grounds
- Size wires and fuses for the actual circuit loads
- Have the harness inspected if you are not experienced with automotive wiring
Compatibility Notice
Northline Parts does its best to list all known compatible models. The correct part may fit an application that is not shown above. Model year, production date, serial number, engine or equipment specification, installed options, and previous repairs can change fitment. Match the original part, reference number, dimensions, connectors, mounting points, and product photos before purchase.
Frequently Asked Questions
Q: Is this a complete plug-and-play LS harness? A: No. It is a fuse-block, relay, and diagnostic kit for reworking a compatible factory harness.
Q: Will it disable VATS or program the ECU? A: No. Controller programming is a separate service.
Q: What do the two relays typically control? A: The kit is arranged for ignition power and fuel-pump control in compatible builds.
Q: Is this an original-equipment part? A: No. This is a new aftermarket product. Brand names and part numbers are used only to identify compatible applications.
Part Summary
keywords: LS swap fuse block kit, 12 way GM engine harness fuse box, LS fuel pump ignition relay kit, OBD2 LS harness rewire, 4.8 5.3 5.7 6.0 swap wiring
Brand names, model numbers, and reference part numbers are used for identification and compatibility purposes only. Verify the original component, specifications, and application before purchase.