Comparison

Battery monitoring that works when you're not there

A €30 Bluetooth monitor shows voltage when you stand next to the car. QZ reports over 4G wherever the car parks — and warns you before the car won't start.

See QZ pricing →

The QZ device — a 12V car battery guard

Where a Bluetooth monitor stops

For the money, a Bluetooth monitor is a decent tool: at the car, it shows you the voltage. Its limit is structural — roughly 10 metres of range, and you have to open the app yourself. Batteries tend to die exactly when you're away.

How QZ works

1
Connect it at the batteryTwo leads: red to positive, black to a chassis ground. No CAN bus, no OBD, no wiring into the car — warranty-safe. Installation takes about 10 minutes.
2
It reports over 4GSIM and connectivity are included in the price. QZ sends data from anywhere with even weak mobile signal — underground garage, another city, winter storage. In Storage mode it draws about 5.3 mA, roughly 1.5% of a 60 Ah AGM battery per week.
3
You get a plain-language verdictThe app speaks in conclusions, not raw numbers — for example, "battery needs charging before the weekend". A push notification arrives before the car won't start.

A real case from our fleet

A Maserati in our fleet: QZ flagged the weakening battery days ahead as the voltage slid to 11.98 V. The owner replaced it calmly, before being stranded. That is one real story, not a guarantee — but when a battery weakens gradually, QZ can warn days in advance — as in this case.

Common questions

Why pay €199 when a Bluetooth monitor costs €30?
If the car sleeps in your own garage and you check it weekly, the €30 device is fine — we say that plainly. QZ is for what that device structurally cannot do: watching the battery when you are not there. 4G reporting, the SIM and the first year of service are included from €199.

If your car sits next to a power socket, a quality maintenance charger is a legitimate choice — on our own test bench we use the CTEK MXS 5.0. We have no ties to the manufacturer; we recommend what we use ourselves. And with QZ installed, it can confirm the charger is actually charging.

I'm not comfortable installing electronics in my car.
It's two leads at the battery — the same operation as connecting a charger. No cut wires, no CAN bus, no OBD. About 10 minutes.

My garage is underground — will there be signal?
QZ needs only ordinary mobile signal, not Wi-Fi or Bluetooth. If your phone gets any signal in the garage — even weak — the device connects. Underground garages are exactly where a Bluetooth link with roughly 10 m of range cannot help at all.

Will it void my car's warranty?
No. QZ connects only at the battery — it never touches the CAN bus, the OBD port or the vehicle wiring. From the car's point of view, it is the same connection as a maintenance charger.

See QZ pricing →

From €199 one-time, including the first year of service. Details in the pricing section.

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