Before you start
Gather the appropriate supplies and review the specific equipment manual.
- Battery manual
- Installed battery monitor
- Flashlight
Step-by-step instructions
Identify battery chemistry
Verify whether each bank is lead-acid, AGM or lithium and locate the battery-management and charging documentation.
Read the monitor at rest
Note voltage, state of charge, current and temperature; interpret them using the correct battery chemistry and monitor calibration.
Look for obvious damage
Without disconnecting energized cables, inspect for heat discoloration, corrosion, unsupported wires or loose battery hold-downs.
Compare charging behavior
Check charger settings and peak voltages against the battery manufacturer specifications, especially for lithium systems.
Make a maintenance record
Write down readings, date and any alarm history so a developing issue is easier to recognize.
Safety note
Battery short circuits can cause fire and severe injury. Do not remove live terminals or open high-current equipment without proper isolation and expertise.
Key takeaway
A battery monitor trend is more meaningful than a single voltage reading.
Keep this job on your maintenance schedule
Save the topic as a maintenance task, choose a due date or engine-hour target, and record future service. Free and stored on your device.
Add to my maintenance plannerThis guide is for general education. Follow your equipment manufacturer’s instructions, current navigation guidance and applicable marine safety standards. When uncertain, use a qualified marine professional.