Mazda CX-5 2021 Owner's Manual page 121

About the SCR system
WARNING
Be careful not to allow the DEF to run out. If the DEF completely runs out, the SCR system will
not operate normally:
If the vehicle runs out of DEF, the vehicle speed is restricted in steps to prevent contaminants
from being exhausted. When the remaining distance-to-empty reaches 0 km (0 miles) in the
final stage, the engine is forced to idle. For replenishment of the DEF supply, consult an
Authorized Mazda Dealer.
CAUTION
Use a Mazda genuine product or a product conforming to ISO22241-1 for DEF. If
incompatible DEF is used, the SCR system may not operate normally. For the recommended
DEF, consult the nearest Authorized Mazda Dealer.
NOTE
When the remaining distance-to-empty is 640 km (400 miles) or shorter while the DEF

warning indication is displayed, the SCR warning light turns on and the vehicle speed is
restricted. In addition, if there is a problem with the SCR system/DEF and the remaining
distance-to-empty is 200 km (125 miles) or shorter, the SCR warning light flashes and the
vehicle speed is restricted.
DEF needs to be replenished periodically according to the scheduled maintenance

information. If a warning message is displayed in the multi-information display or the
SCR warning light flashes, consult an Authorized Mazda Dealer.
Normally, the vehicle can be driven about 12,000 km (7,500 miles) before the DEF needs

to be replenished.
▼ Engine Exhaust (Carbon monoxide)
WARNING
Do not drive your vehicle if you smell exhaust gas inside the vehicle:
Engine exhaust gas is dangerous. This gas contains carbon monoxide (CO), which is colorless,
odorless, and poisonous. When inhaled, it can cause loss of consciousness and death. If you
smell exhaust gas inside the vehicle, keep all windows fully open and contact an Authorized
Mazda Dealer immediately.
Before Driving
Fuel and Emission
3-31