How do I test if my DC-DC charger is working?

With engine running, DC-DC charger should show ~14V output. If 0V, charger has failed or lost power

Troubleshooting

Why Is My Leisure Battery Not Charging While Driving?

Q: Why is my leisure battery not charging while driving?

Common causes include faulty DC-DC charger, alternator not charging main battery, dead leisure battery, or incorrect charger settings

Your leisure battery won't charge while driving? This troubleshooting guide covers why your DC-DC charger or leisure battery isn't charging, common causes (faulty charger, alternator issues, blown fuses), and step-by-step fixes to get charging working again.

Whether you have a Victron Orion, Renogy, or other DC-DC charger, a non-charging leisure battery is one of the most frustrating campervan electrical issues. This guide helps diagnose the problem quickly so you can get back on the road with a fully charged auxiliary battery.

The Most Common Causes

DC-DC Charger Not Working

The Orion or other DC-DC charger may have failed, tripped, or lost power. Check for blown fuses and proper battery connections.

Alternator Not Charging Main Battery

If your engine battery isn't charging, the DC-DC charger won't have power to charge your leisure battery.

Flat or Dead Leisure Battery

A completely dead lithium battery can sometimes fail to accept a charge. May need professional revival.

Wrong DC-DC Charger Settings

Some chargers need programming for lithium vs lead-acid. Incorrect settings prevent charging.

Troubleshooting Steps

1. Check the Fuse

Look for the fuse between your engine battery and DC-DC charger (usually 80-100A). A blown fuse will prevent any charging.

2. Verify Battery Voltage

Use a multimeter to check: Engine battery should show 13.5V+ while running. Leisure battery shows what it's at (e.g., 12.4V = 50% charge on lithium).

3. Test DC-DC Charger Output

With the engine running, the DC-DC charger should show ~14V output. If it shows 0V, the charger has failed or lost power.

4. Check Battery Protect Settings

If you have a Battery Protect device, it may be cutting off charging if your leisure battery is too low. Check the low-voltage disconnect setting.

Quick Fix Checklist

Is your engine battery actually charging? (Check while engine is running)

Is the fuse between main and leisure battery intact?

Are all battery connections tight and free of corrosion?

Is the DC-DC charger LED showing activity when engine is running?

For lithium: Is the battery below the cut-off voltage?

Are you using the correct DC-DC charger for lithium? (Not all work with lithium)

When to Call a Professional

If you've checked the fuse and connections but your leisure battery still won't charge, the DC-DC charger may have failed. Contact us for diagnostics and replacement.