Battery Empty or Missing

What does E4-8 mean?

The system's battery is either empty or entirely missing. This warning indicates that non-volatile data, such as configuration parameters, retained variables, or real-time clock settings, may be lost during power cycles if the issue is not resolved. This can lead to system re-configuration needs on every restart.

• Depleted lithium battery (e.g., CR2032 or specific module battery pack) reaching its end-of-life cycle (typically 5-10 years).
• Battery compartment terminals corroded or bent, preventing proper electrical contact with the installed battery.
• Battery physically removed from the module and not replaced, often during maintenance or troubleshooting.
• Internal charging circuit failure (for rechargeable batteries) preventing the battery from holding a charge.
• High ambient temperature (e.g., above 60°C) accelerating battery discharge and degradation.

Click steps to track your progress.

1. 1

   1. Locate the battery compartment on the module (e.g., under a front cover, on the main board).

2. 2

   2. Measure the voltage of the installed battery using a multimeter (e.g., expect ~3V for a new CR2032). If below 2.5V, it is depleted.

3. 3

   3. Carefully remove the old battery, inspect the battery holder for corrosion or bent contacts, and clean them with a contact cleaner or small brush.

4. 4

   4. Install a new, manufacturer-specified battery (e.g., CR2032 lithium primary cell, specifying voltage and capacity) with correct polarity.

5. 5

   5. After battery replacement, power cycle the module and re-enter any non-volatile parameters (e.g., Real-Time Clock, specific retain values) that might have been lost.