PEUGEOT 308 Handbook page 276

Checks
In the event of a fault with the the SCR emissions control system
A system that prevents engine starting
is activated automatically from
650 miles (1 100 km) after confirmation
of a fault with the SCR emissions
control system. Have the system
checked by a PEUGEOT dealer or a
qualified workshop as soon as possible.
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In the event of the detection of a fault
When switching on the ignition, the UREA,
SERVICE and diagnostic warning lamps comes
on, accompanied by an audible signal and the
display of a message "Emissions fault" to signal
a fault with the emissions control system.
If it is a temporary fault, the alert
disappears once the exhaust gas
emissions return to normal.
During an authorised driving phase (between
650 miles and 0 miles) (1 100 km and 0 km)
If a fault with the SCR system is confirmed
(after 30 miles (50 km) covered with the
permanent display of the message signalling
a fault), when switching on the ignition, the
SERVICE and engine diagnostic warning lamps
come on and the UREA warning lamp flashes,
accompanied by an audible signal and the
display of a message (e.g.: "Emissions fault:
Starting prevented in 150 miles") indicating the
remaining range express in miles or kilometres.
While driving, the message is displayed every
30 seconds while the fault with the SCR system
persists.
You should go to a PEUGEOT dealer or a
qualified workshop as soon as possible.
If you fail to do this, there is a risk that you will
not be able to start your engine.