You've plugged into mains power but nothing on 240V is working — no air con, no power points, no microwave, no charger. Most of the time it comes down to one of three things: no incoming shore power, a tripped RCD (safety switch), or a tripped breaker. This guide walks you through the safe checks you can do yourself before lodging a support ticket.

Switchboard location and layout vary by model and year — most Mars vans have the 240V panel near the foot of the bed or in a service cupboard.

Safety First — 240V Can Kill

• Do not remove covers from 240V outlets, switchboards or appliances.
• Do not attempt to repair or modify any 240V wiring yourself.
• If you smell burning, see smoke, see melted plastic, hear buzzing, or feel heat at a plug or outlet — turn the power off at the mains, disconnect the lead and contact a licensed electrician.
• If you are unsure at any point, stop and lodge a ticket with photos.

Before You Start

Common symptoms of a 240V issue:

• No power from any internal 240V outlets
• Air conditioner won't turn on (when normally it would on shore power)
• Microwave won't power up
• Battery charger isn't charging while plugged into 240V

Helpful clue: If your 12V system still works (lights, water pump, fridge in 12V mode) but 240V doesn't, the fault is in the incoming power, lead, RCD or 240V switchboard — not the battery.

Step 1 — Confirm the Power Source Is Live

• Caravan park: Is the pedestal switch ON? Some sites have multiple switches. Ask park staff to confirm the outlet is working if you can.
• At home: Test the outlet with a known-good appliance (a lamp or charger). Check the house RCD hasn't tripped.
• Generator: Make sure it's running cleanly and supplying stable power. If unsure, test the van on shore power first to rule out generator issues.

If there is no power at the source, the issue is with the park, the house, or the generator — not the caravan.

Step 2 — Check the Power Lead

• Use a proper heavy-duty 15A caravan lead. Avoid cheap indoor extension leads.
• Inspect for cuts, crushed sections, damaged pins, burnt or melted plug ends.
• Check both ends are firmly seated — one in the pedestal/house outlet, the other in the caravan 240V inlet.
• Feel the plug carefully. If it's hot, switch off and disconnect immediately.
• If the lead is damaged, do not use it. Replace it or have a qualified person check it.

Step 3 — Find Your Internal 240V Switchboard

Your Mars caravan has a small switchboard with a Safety Switch (RCD) and one or more circuit breakers. It's typically located near the foot of the bed or in a service cupboard. Exact position varies by model.

Step 4 — Reset the RCD (Safety Switch)

• If the RCD is in the OFF position or sitting halfway, it has tripped.
• To reset: push it fully OFF, then back to ON.
• If it trips again immediately, move to Step 6.

Step 5 — Reset Tripped Circuit Breakers

• Look for any breakers in the OFF or halfway position.
• Reset the same way: fully OFF, then ON.
• If a breaker won't stay on, stop and book a service call.

Step 6 — If It Keeps Tripping, Isolate the Cause

1. Unplug every 240V appliance inside the van — kettle, toaster, microwave, chargers, phone bricks, the lot.
2. Reset the RCD and breakers.
3. If they hold, plug appliances back in one at a time until you find the one causing the trip.
4. If they still trip with everything unplugged, the fault is in the van wiring or a hard-wired appliance circuit — book a service call.

Step 7 — "Only One Thing Isn't Working" Scenarios

• Only one outlet dead: It may be on a different circuit, or a local outlet fault. Try a known-good appliance to rule out the appliance itself.
• Only the air con isn't working: Check the aircon's dedicated breaker (if separate) and confirm you're actually on shore power, not battery/inverter.
• Only the charger isn't running: Locate the charger (often under a seat or bed). Check for indicator lights showing it has 240V input. If everything else has power but the charger has none, book service.

Quick Diagnosis Cheat Sheet

• No 240V anywhere → check pedestal/outlet, lead, then RCD and breakers
• RCD trips instantly → usually an appliance fault or moisture issue; unplug everything and retry
• Breaker (not RCD) trips → commonly an overload on that circuit; reduce load and retry
• Works at home but not at the park → pedestal or site wiring issue; try another outlet or site
• Works at the park but not at home → home outlet, circuit or lead compatibility issue

Common Causes

• Faulty or overloaded appliance (kettle, heater, coffee machine)
• Water or moisture in an external outlet or appliance, especially after rain or washing
• Damaged power lead or loose connection
• Multiple high-draw appliances on a single circuit
• Switchboard trip due to a genuine safety fault

When to Stop and Lodge a Support Ticket

Stop troubleshooting and contact Mars support or a licensed electrician if:

• The RCD or breakers won't stay on even with everything unplugged
• You see heat, scorch marks, melting, or smell burning
• Power is intermittent — works, then drops out, repeatedly
• The issue is new and you can't identify an appliance causing it
• You don't feel safe or confident performing the checks above

What to Include in Your Support Ticket

So we can help you fast, please include:

• Your Mars model + year (and VIN if available)
• Where you are plugged in: caravan park, home, or generator
• Whether other vans or appliances on the same outlet are working
• Photo of the 240V switchboard with breaker positions visible
• Photo of the power lead plugs at both ends
• If it's tripping, a short video showing the reset and trip
• List of appliances that were being used when the issue started
• A short description of what you've already checked

Important: Do not open electrical panels or carry out any internal 240V work yourself. All internal mains work must be done by a licensed electrician or authorised Mars service technician.

Related articles: Power 101 — Understanding 12V vs 240V· Charging Explained: Vehicle, 240V & Solar· 12V System Basics / No Lights, No Pump