How to jump-start your car with jumper leads

Before you jump-start your car, double-check that the issue is a flat battery that can be safely jump-started:

• Turn your key in the ignition. If you hear a rapid clicking but no engine turnover, this likely indicates a flat battery that can be jump-started.
• Check your headlights. If they’re very dim or won’t turn on, this confirms a flat battery.
• Look at your dashboard. If no lights appear when turning the key, your battery is completely flat.

WARNING – do NOT attempt to jump-start your car and HOLLER FOR A MARSHALL if:

• Battery is visibly damaged, leaking, or has corrosion
• Engine turns over quickly but won’t start
• Dashboard lights work normally
• You’ve already attempted a jump start that failed
• Your car has a start/stop system or is a hybrid

If you’ve confirmed it’s a simple flat battery, follow the jump-start guide below. For anything else, call 1300 627 742 for roadside assistance from Marshall Batteries. Our technicians are available 24/7 with no membership fees required.

To jump start your car, you’ll need:

Essential equipment:

• Jumper cables/leads (good quality, 4-6 meters long)
• A working vehicle with a compatible 12V battery
• Safety gloves (to protect from acid and electrical shock)
• Safety glasses (to protect from sparks)

Safety gear if you’re on the roadside:

• Flashlight for low-light conditions
• Battery cleaning brush (if terminals are corroded)

Step-by-Step jump-start Instructions

1. Position vehicles correctly:

• Park the working car close but NOT touching your car
• Ensure bonnets are close enough for cables to reach both batteries
• Both cars must be completely OFF (including radio, lights, A/C)
• Put both cars in Park (automatic) or Neutral (manual)
• Engage handbrakes on both vehicles
• Remove keys from both cars

2. Prepare the jumper leads:

• Completely separate and untangle cables
• Keep red and black clamps from touching at all times
• Check cables for any damage or exposed wire

3. Connect the jumper leads IN THIS EXACT ORDER

• RED clip to the positive (+) terminal of your dead battery
• Other RED clip to positive (+) terminal of working battery
• BLACK clip to the negative (-) terminal of working battery
• Other BLACK clip to clean, unpainted metal under your bonnet

WARNING: Never connect the final black clip to your dead battery SAFETY CHECK: Ensure cables aren’t touching any engine parts

4. Start the jump:

• Start the working vehicle
• Wait 2-3 minutes to allow initial charge
• Try starting your car
• If it doesn’t start, wait another 2-3 minutes and try again

5. Disconnect in EXACT REVERSE ORDER:

• Remove BLACK from your car’s metal surface
• Remove BLACK from working battery
• Remove RED from working battery
• Remove RED from your battery
• Replace any protective terminal covers

6. After successfully jump-starting your car

• Keep your engine running for at least 20-30 minutes
• Drive if possible – this helps charge the battery better
• Don’t turn off the engine before the 20-minute mark

 7. Failed jump-start?

If the engine doesn’t start after following the correct jump-start procedure, you likely have a more serious electrical issue. Stop attempting further jump-starts to prevent potential damage. Call Marshall Batteries on 1300 627 742 or find your nearest store – our technicians will diagnose the problem and can either:

• Replace your battery on the spot
• Identify if there’s an alternator or starter motor issue
• Provide safe towing if needed

Remember: Repeated failed jump-starts can damage your vehicle’s electrical system. For your safety and to prevent costly repairs, let our experts handle it if the first attempt doesn’t work.

Quick FAQs about jump-starting your car