Chevrolet/GMC Duramax BD X-Tuner Installation

Pre-Installation
The BD X-Tuner for the GMC/Chevrolet Duramax (LBZ Engine) is a very simple instrument to operate. All operations take place inside the cab with the downloader hooked up to the OBD II diagnostic port. Operating this downloader does not require a mechanical background. While operating this downloader we encourage you to simply follow the instructions provided on the screen of the X-Tuner; the instructions on the screen are easy to read and comprehensive.
The X-Tuner is meant for the 6.6L Duramax LBZ Engine (2006+), and cannot be used for any vehicle other than this specific application.
This instruction booklet will provide you with a detailed description on how to perform downloader operations and is split up into easy-to-read sections labeled with headings. Once you have downloaded a power program into your vehicle, remember to always keep the downloader with you, if possible as you may want to change the power program that is loaded, or to check and erase Diagnostic Trouble Codes (DTC’s) on the road.
Installation
Make sure that your vehicle is in the key off/engine off position, with all electronics (such as the radio) turned off before you plug in the X-Tuner. Locate the fuse box inside the engine compartment, on the driver’s side. Remove the fuses marked in the picture above. There are two fuses that have to be removed in total...

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