BMW X3 Owners Manual: Have the diesel exhaust fluid replenished

The reducing agent is added by the service center within the context of regular maintenance.

It may be necessary to have the fluid replenished several times under particular circumstances, e.g., if the vehicle is driven in a particularly sporty style or if it is driven at high altitudes.

The reducing agent must be replenished as soon as the reserve display appears in the instrument cluster to avoid not being able to restart the engine.

Diesel exhaust fluid at low temperatures Due to its physical properties, it is possible that the reducing agent may also need to be replenished between regular maintenance appointments if it is exposed to temperatures under + 23 ºF/- 5 ºC. In this case, add reducing agent only immediately before driving off.

The need to replenish it is indicated by the Reserve display in the instrument cluster.

At temperatures below + 12 ºF/- 11 ºC, the filling level cannot be measured in some cases.

After adding reducing agent, the Reserve Display is displayed only until the fill level can be measured again.