Replacing an M3 BIOS battery

1 Introduction

1.1 Problem description

If the BIOS battery of the M3 becomes fully drained, this can cause issues with the display and the system’s internal clock, and settings of the trolley's mainboard are lost. Whenever the trolley is shut down and disconnected from any power source, the BIOS chip is powered by a 3V CMOS battery to keep its settings stored. If this battery is empty or disconnected, settings will be lost and the trolley cannot boot correctly. This often happens when the M3 has not been used for a long time as the BIOS is constantly drained in this scenario. It can be fixed by replacing the old BIOS battery and then bringing the BIOS settings back to their original state.

1.2 Pre-requisites

To replace the BIOS battery you will need:

• Extract the files attached to this article and place them one by one on an empty USB stick. 

• a 2.5mm allen key

• USB-hub with three ports 

• Cable-tied mouse (connected to the USB-hub).

• Cable-tied keyboard (connected to the USB-hub).

• a new 3V CMOS battery (CR2032) with two-pin connector:

2 Troubleshooting procedure

2.1 Battery Removal

Warning: Remove the electrical connector from the mains supply. 

1. To gain access to the interior of the device, remove the screws securing the cover to the body of the M3.

2. Remove three screws indicated and remove the frame around the mainboard.

   Note: Be careful not to bend or break any of the connectors.

     

3. The battery is visible underneath the frame, as show here:

   

4. Disconnect the the two electrical pins from the battery.

5. Remove the old battery by pulling it from the device, it’s held in place with a little adhesive.

6. Insert the battery into place, and connect the two electrical pins.

7. Use a little hot glue or double sided tape to hold it in place.

2.2 Reflashing the BIOS

2.2.2 Connect the USB ports

1. To return the trolley to its NavVis-specific BIOS settings, download the zip file attached to this article, extract the files and place them one by one, without the folder, on to an empty USB stick:

   • q87t.CAP

   • afterinstallation.CMO

2. Get the following tools and connect them to the USB-port below the M3's display:

   • a USB-hub with three ports (connected to the M3).

   • a cable-tied mouse (connected to the USB-hub).

   • a cable-tied keyboard (connected to the USB-hub).

   • the USB-stick with the two installation files.

2.2.3 Enter the BIOS menu

1. Switch on the NavVis M3 and before the device fully initializes press F7 on the keyboard to enter the BIOS menu 

2. A dialog box displays Enter Advance Mode? Click Ok.

   

3. In the Advanced mode click Tool. The tools menu is displayed.

4. Click ASUS EZ Flash 2 Utility.

   

5. In the ASUS EZ Flash 2 Utility tool, select the installation file Q87T.CAP and press Enter to confirm.

   

6. The BIOS version will be installed on the M3. After the installation, the BIOS system will return to the Advanced Mode main page.

2.2.4 Update the BIOS settings

1. In the Advanced Mode page under Tool, select the option ASUS Overclocking Profile.

   

2. In the new overview select Load/Save Profile from/to USB Drive. Select the file afterinstallation.CMO from your USB-stick and confirm the choice by pressing Enter on the keyboard.

   

3. After the setup click Exit and select Save Changes and Reset in the window displayed.

   

4. Once the BIOS settings have saved and the system has left the BIOS menu, remove the USB stick as soon as the screen turns black. Otherwise the USB stick might be selected automatically to become the new primary disk of the system, which leads to another issue.

2.3 Verify the new setup

Switch on the M3, it should be able to scan as usual. To test that every step has been completed correctly perform the following:

1. Switch on the M3 and remove the M3 battery.

2. Switch on the M3 and the new BIOS battey should take over as the power source, initializing as usual.

Note: M3 Support and Services have been discontinued by NavVis in December 2021. All tests and troubleshooting actions described here are done at your own risk. Repairs of hardware components and technical Support for any Software related to M3s can no longer be provided or purchased.