HP Tuners Instructions for 2017–2026 L5P Duramax Customers

Please follow these instructions carefully when using HP Tuners for your 2017–2026 L5P Duramax tuning.

Step 1: Download the Latest HP Tuners Beta Software

Before reading or flashing any files, make sure you are using the latest version of HP Tuners VCM Suite Beta.

This can be downloaded for free from the HP Tuners website.

You will need:

• VCM Editor Beta
  This is used to read your stock files and flash the modified tune files onto the vehicle.
• VCM Scanner Beta
  This is used for data logging, diagnosing issues, checking codes, and clearing codes.

Do not use an outdated version of HP Tuners. Using old software can cause reading, flashing, or compatibility issues.

Step 2: Make Sure You Have the Correct Credits

Before flashing any tune files, make sure your HP Tuners device has the correct credits already purchased and downloaded onto the device.

Credits must be purchased separately through the HP Tuners website.

You will need to register your HP Tuners device under your own email/account, then purchase the required credits for your vehicle.

Depending on what you are tuning, you may need credits for:

• Engine only
• Transmission only
• Engine and transmission

You are responsible for purchasing the correct credits needed for your vehicle before attempting to flash the tune.

Step 3: Pull Your Stock Readouts

Before we can build your custom tune files, you must pull and save your stock readout files using VCM Editor Beta.

You will need to pull two separate files:

1. Engine Tune Readout
2. Transmission Tune Readout

This means you must read the engine tune, save it, and send it to us. Then you must read the transmission tune separately, save it, and send that file to us as well.

These are two separate files. Do not send only one file unless you are only tuning one controller.

Once completed, email both files to us so we can begin modifying them.

Step 4: File Revision Process

After we receive your stock engine and/or transmission readout files, we will modify your first tune file and send you one revision.

You will need to load that revision onto the vehicle and confirm that everything is working properly.

Once you confirm the first modified file is working correctly, we will then send the second modified file you requested.

Step 5: Loading the Tune File

When loading the tune file with HP Tuners, you must use:

WRITE ENTIRE

Do not use:

Write Calibration Only ( unless instructed )

The file needs to be loaded as a full write to make sure the tune is properly installed.

Step 6: Flash the File Twice

After loading the tune file the first time, you need to load the same file again using Write Entire.

This means you will write the tune file at least two times.

Sometimes HP Tuners may not fully write the complete file the first time. Writing the file twice helps make sure the full calibration is properly installed.

Step 7: Clear Codes Twice

After the tune file is loaded, open VCM Scanner Beta and clear the codes twice.

You should clear codes with:

1. Engine off, key on

After clearing codes, cycle the ignition and verify there are no active codes before driving the vehicle.

Important Reminders

• Use the latest HP Tuners VCM Suite Beta only.
• Use VCM Editor Beta to read and flash tune files.
• Use VCM Scanner Beta to data log, diagnose, and clear codes.
• Make sure the correct HP Tuners credits are already purchased and downloaded onto your device.
• Credits are purchased separately through HP Tuners.
• Engine and transmission files must be read and sent separately.
• Always save your stock files before loading any modified files.
• Always use Write Entire when flashing.
• Do not use Write Calibration Only. Unless instructed to
• Flash the same file twice using Write Entire.
• Clear codes twice after flashing.
• Make sure the vehicle has good battery voltage during the flashing process.
• Do not unplug the MPVI device, disconnect the laptop, or turn the key off during the write process.

Failure to follow these steps can cause flashing issues, incomplete writes, communication problems, or delays with your tuning process.