Common problem so
open bonnet go to near side inner guard rhd models
follow the joint where outer wing attaches to inner guard close to top just above battery
you will see several bunches of cables rising into a detachable plastic frame holding fuses and relays
check cable plugs were they click /attach to the relays and fuses 9 out of 10 times you will find when you hit potholes etc the shock is enough to dislodge one or more of the plugs from this block which causes tail lights side marker lights and dash lights to go off
l k phillips
April 2022