These instructions apply to the Mazda 3 Mk3 (BM/BN) 2013-2018.
For other models, please choose your vehicle here.
A flat 12 volt battery is the most common reason a Mazda 3 (BM/BN) won’t start. If the dashboard is dim, the starter only clicks, or nothing happens at all, a jump-start from a healthy 12 V vehicle or a jump pack will usually get you going. Work through the steps below in order — the sequence matters for safety.
Before You Start
- Use a 12 volt source only. Never use a 24 V supply (two batteries in series) — it will damage the starter, ignition and electronics.
- Both cars must be switched off, not touching, with the parking brake set.
- Don’t jump-start a battery that is frozen or visibly leaking.
- The 12 V battery is in the engine bay, on the right-hand side; lift off the cover to reach the terminals.
How to Jump-Start the Mazda 3
- Remove the battery cover on the flat car to expose the positive (+) and negative (−) terminals.
- Connect one end of the red lead to the positive (+) terminal of the flat battery.
- Connect the other end of the red lead to the positive (+) terminal of the donor battery.
- Connect one end of the black lead to the negative (−) terminal of the donor battery.
- Connect the other end of the black lead to a bare metal ground point on the flat car — a bracket or engine lug well away from the battery, not the negative terminal. This keeps any spark away from battery gases.
- Start the donor car and let it run for a few minutes.
- Start the Mazda 3. Once it runs, remove the leads in the exact reverse order (ground first, then donor negative, then both positives).
- Refit the battery cover.
On cars with the i-ELOOP system, the i-ELOOP indicator may flash after starting. Let the engine run until it goes out before driving; the steering can feel heavier while it flashes, which is normal.
After a Jump-Start
Drive for at least 20–30 minutes, or put the battery on a charger, to restore charge. If the battery goes flat again within a day or two it is worn out or there is a drain — have it tested.
Never try to bump- or tow-start the car. Once running, you may need to re-initialise the power windows and reset the tyre-pressure monitor after the battery was low.
Frequently Asked Questions
Where do I connect the negative lead on a Mazda 3?
Not to the flat battery’s negative terminal — connect it to a bare metal ground point on the engine or body, away from the battery, so any spark is clear of battery gases.
Can I jump-start a Mazda 3 with a jump pack?
Yes. A 12 V lithium or lead-acid jump pack works well; follow the same order (positive first, then the pack’s negative to a ground point).
Why won’t my Mazda 3 start even after a jump?
If it still won’t crank, the battery connections may be corroded, the battery may be completely dead, or the fault is elsewhere (starter or immobiliser). The car may store a fault code you can look up on autodtcs.com.
For the correct disconnect-and-reconnect sequence when replacing the battery, see our Mazda 3 battery disconnect guide, and decode any warning light on autodtcs.com.
Independent guide — not affiliated with Mazda. Always follow your official service manual and safety precautions. Read our full disclaimer.