How to wire GM’s LS using Haltech’s Terminated Harness

How to wire GM’s LS using Haltech’s Terminated Harness

GM’s LSs are some of the most popular engines on the planet. They are super strong, reliable and relatively inexpensive to buy and service. Add to it an almost infinite supply of spares and aftermarket performance parts and you begin to see why LSs are finding their way into a growing number of performance builds.


Without a doubt, one of the most daunting tasks involved in an engine conversion is the wiring process. Luckily, if your project car is using an LS (or one of the engines supported by the Haltech Terminated Engine Harness range) this process is now relatively straight forward.

On the ECU side the Terminated Engine Harness includes Haltech ECU connectors and an optional CAN Wideband connector.


On the engine side you’ll find an array of fully terminated engine connectors including a pre-wired plug for the OEM 7 Pin coil harness connector and a group of unterminated in-cabin wires. All the wires are clearly labelled eliminating any guesswork.


The harness also includes a fuse box with five fuses and five relays.


We have also included a 2″ gromit to protect the harness as it passes through the firewall.


With a Haltech Terminated Harness your LS2 can be wired up and running in a few hours and, when installed in conjunction with a Haltech Elite 2500 ECU, it opens the door to virtually limitless performance modification and tuning options for your vehicle. Haltech Terminated Harnesses are available for most popular LS variants of engines.


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