2006 Vauxhall Vivaro jerking / airbag

hi when was it last serviced i would start with a full engine service oil and filter using correct oil grade air and fuel filters check all pipes for damage and leaks remove and clean egr valve and check pipes of egr valve for carbon build up then use a fuel system cleaner sdded to fuel forte is good then see if any improvement spanner symbol on could just be service overdue light get this re-set check seat belt pre- tensioner wire connectors for poor connections but make sure ignition off while doing this if ok you will have to have codes read to locate fault in air bag system