Diagnostic Aids
WARNING: This page is about a different car, the 2000 Isuzu Hombre. However, it is still accessible from the selected car via links, so may be relevant.
An intermittent DTC P0530 set along with DTC P0405 indicates a possible short to ground in 5-volt reference circuit. This condition will cause scan tool to display incorrect EGR ACTUAL POSITION value. Check for loose or corroded connections, Inspect wiring and connectors for damage.