A computer in your car monitors sensors that measure such things as engine temperature, exhaust gas mixture, and other metrics that would mean very little to you unless you're a serious automotive troubleshooter. What Is OBD? Since the mid-1990s vehicles have had a built-in troubleshooting system known as OBD.$115,929 Estimated Payment $1,131 / month Figure based on a stock vehicle with OH rates with $100/$300k Liability/UM/UIM limits. If your car supports OBD II or EOBD, then you can already use almost 5000 generic OBDII codes.These codes are from PowerTrain series (P0XXX, P2XXX, P34XX), Body Series (B0XXX), Chassis series (C0XXX), Network series (U0XXX, U2XXX, U3XXX). OBDII/EOBD diagnostics trouble codes definition.