Pixel 6 / 6A / 6 Pro IMEI 0 Fix: CPID & NV Restoration Guide

The first-generation Google Tensor (Tensor G1) smartphone family—comprising the Google Pixel 6 (oriole), Pixel 6A (bluejay), and Pixel 6 Pro (raven)—uses a Samsung Shannon 5123 modem. An interrupted firmware operation, damaged provisioning data, or a hardware fault can present as “IMEI 0”, “Null IMEI”, or “Baseband Unknown”. The symptom alone does not establish which component failed.

This guide documents a third-party workflow using the Google Pixel Technicians Toolkit V3. GSM6 has not retained a device/build/update test matrix that proves which variants it repairs or whether a result survives a later OTA. Treat the procedure as experimental, preserve the device’s original identity data, and use Google or an authorized repair provider when the fault may be hardware-related.

Technical Architecture: Tensor G1 and Shannon Modem Baseband Partitioning

Unlike legacy Qualcomm-powered Pixel devices (Pixel 1 through Pixel 5) that stored radio calibration in standard EFS partitions accessible via Qualcomm diagnostic (DIAG) ports, Tensor G1 devices handle radio provisioning through specialized Shannon baseband blocks:

1. Shannon Modem Structure: The Samsung Shannon 5123 modem communicates directly with the Tensor SoC over dedicated PCIe and shared memory channels.
2. CPID and Radio Calibration Blocks: The Chipset Persistent ID (CPID) and cellular radio parameters are written to hardware-protected Non-Volatile (NV) partition blocks.
3. Diagnosis remains device-specific: A null IMEI or unreadable baseband can have more than one cause. This article does not prove that a particular handset has a CPID/NV desynchronization or that the third-party tool can repair it.

The toolkit vendor describes its operation as an NV/CPID restoration. That implementation and its persistence have not been independently verified here. Do not infer success from an on-screen status alone: verify the original factory-assigned identity, baseband status, calls, data, and emergency-service behavior after the procedure.

Hardware Codename and Model Reference

Verify your specific Pixel 6 hardware revision before beginning firmware preparation:

Ensure that any factory image archive downloaded matches your exact hardware codename. Flashing mismatched firmware partitions across models will prevent the device from booting.

Prerequisites and Setup Requirements

• Official Factory Image: Download the official stock factory image matching your device codename directly from the Google Developers repository.
• Google Pixel Technicians Toolkit V3: Download and install the toolkit from our Toolkit V3 Download Guide.
• USB Driver Suite: Verify that the Android USB Drivers are properly installed so Windows recognizes Fastboot and ADB interfaces.
• Data Backup Warning: Unlocking and relocking the bootloader triggers a complete hardware factory reset. Back up critical local files before beginning.

Step-by-Step Procedure to Repair Pixel 6 IMEI 0

The following stages describe the tool vendor’s workflow. It requires bootloader unlocking, destructive resets, and temporary root. Removing a patched image later does not prove that every security or integrity check returns to its previous state.

1. Download Stock Factory Firmware and Technicians Toolkit

1. Download the full factory image .zip for your specific Pixel 6 model (oriole, bluejay, or raven).
2. Install the Google Pixel Technicians Toolkit V3 on a 64-bit Windows PC.
3. Launch the toolkit with Administrator privileges and complete activation using the daily token.

2. Extract and Patch Pixel 6 Boot Partition in Magisk

Pixel 6 series smartphones running Android 12 launched with the initial ramdisk inside boot.img:

1. Unzip the main factory firmware package, open the internal image-[codename]-[build].zip archive, and extract boot.img.
2. Transfer boot.img to your Pixel’s internal storage.
3. Install the official Magisk application on the device.
4. In Magisk, tap Install > Select and Patch a File, select boot.img, and tap LET’S GO.
5. Transfer the generated magisk_patched.img from the phone’s Download/ directory back to your PC.

3. Flash Factory Firmware and Grant Temporary Root Access

1. Power off the phone, hold Volume Down + Power to enter Fastboot Mode, and connect via USB.
2. In the Technicians Toolkit, navigate to the Flash tab.
3. Select your extracted stock firmware folder and click Flash Factory Firmware to establish a clean partition baseline.
4. Once flashed, return to Fastboot Mode. In the toolkit, select Custom Partition > Boot, select magisk_patched.img, and flash the image.
5. Reboot into Android with fastboot reboot. Open Magisk and confirm that temporary superuser access is active.

4. Execute Tensor CPID and NV Data Restoration

1. With the phone connected to your PC via USB and USB Debugging authorized, open the Tensor CPID tab in the toolkit.
2. Click Fix CPID. The toolkit communicates with the running Android kernel to establish a direct diagnostic session with the Shannon 5123 modem.
3. When the IMEI dialog prompt appears:
   • If your original factory IMEI is already detected in the modem query, click SKIP to lock the existing parameter directly into NV storage.
   • If the parameter reports null or zeroes, enter the authentic 15-digit IMEI assigned to the device (found on the original packaging or SIM tray) and click Apply.
4. Allow the toolkit to write the calibration payload and hardware lock flags. Wait until the status log reports complete success.

5. Restore Stock Boot Partition and Relock Bootloader

To return the boot partition to an official image before considering a relock:

1. Reboot the device back into Fastboot Mode:

   adb reboot bootloader

2. Reflash the original, unpatched stock boot.img extracted in Step 2 to remove temporary Magisk root binaries:

   fastboot flash boot boot.img

3. Relock only after confirming that every flashed partition is the exact, unmodified image for the installed build. Locking with modified or mismatched partitions can make the device unbootable.
4. On the phone display, use the Volume keys to select Lock the bootloader and press the Power button to confirm.
5. The device will perform a final factory reset and reboot into production Android.
6. Complete setup, open the phone dialer, and input *#06# to check the original factory-assigned IMEI. Also test baseband status, calls, SMS, data, and emergency calling where lawful and safe; a displayed number alone is incomplete evidence.

Verification and OTA Limitations

No retained test evidence establishes permanence or future-OTA compatibility. If you choose to apply an update after confirming the device works:

• Navigate to Settings > System > System update.
• Download and apply the latest available monthly Android security update.
• Allow the device to reboot and finalize installation.
• Recheck the original IMEI, baseband version, calls, SMS, and mobile data. Record the exact before/after build identifiers. One successful update transition does not prove compatibility with later releases.

Video Tutorial: Pixel 6 Series IMEI 0 Repair Workflow

For a visual demonstration of the toolkit interface, boot image flashing, and CPID execution, watch the walkthrough below:

▶Play video: Step-by-step video guide

Summary

This workflow may help diagnose or restore the original device identity on some Pixel 6-series configurations, but GSM6 has not independently verified the toolkit payload, supported-build range, security-state recovery, or OTA persistence. Keep exact build records and treat any result as specific to the tested handset.