With the Hyundai i10, P0404 is -

Detailed information on troubleshooting and repairing a p0404 automotive trouble code which refers to an EGR circuit range or performance issue

The glow plug light flashes all the time after around 3 mins after you start the van I took it to a garage and they read the fault code which was P0404 EGR

p0404 Explanation of what a P0404 Exhaust Gas Recirculation Circuit Range Performance engine

p0404 Had my EGR valve replaced 4 weeks ago on MY15 CC D2 and since then had a check engine light in 3 occasions, fault code P0404 EGR Control Circuit Performance