A 12 V battery that drains and leaves the Symbioz unable to unlock or start

Engine / equipment

Renault Symbioz E-Tech full hybrid

Period mentioned

2024–2026

Symptoms

After one or two nights standing, the car will not unlock with the card or start; in other cases, a breakdown that immobilises the car with several warning lights on.

Possible cause described

In Renault’s official E-Tech community, several Symbioz 145 owners report 12 V batteries going flat overnight on low-mileage cars: one had it replaced after the second breakdown and three weeks at the garage, another the day after delivery and another under warranty after insisting. Renault has not published the cause; short trips and leaving the car awake (phone connected, lights) make the drain worse. Another thread describes a Symbioz immobilised with several warning lights that the dealer could not diagnose.

Check for the garage

Ask for a load test of the 12 V battery and a check for software updates; if it keeps going flat, claim it under warranty.

Cost cited in the source

No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.

Sources from the original database