In 1997, Cadillac made the DeVille, Eldorado and Seville. These vehicles used the on-board diagnostic II (OBD II) system, which is the system found on all vehicles made from 1996 to the present. Unlike OBD I systems, OBD II systems are standardized, meaning that diagnostic trouble codes (DTCs) are the same across vehicle types. To read your system's DTCs, you need a code reader. Many readers also provide DTC definitions, which you need to understand vehicle problems.
This code means that you have a failing powertrain component. The powertrain is the system that provides power to your vehicle, and generally consists of the transmission, engine and driveshaft. If you are having trouble with a powertrain component, your service engine soon light will come on. You receive this DTC when your OBD II detects a problem with your torque converter clutch circuit.
If you receive this code, then you probably are experiencing a small leak. This DTC means that there is something wrong your electrical system. But, generally, this DTC refers to a leak at the fuel filler neck, which is the connection between where you put in gas and your fuel tank. You should check here first before moving on to any other system. You receive this error when your OBD II system detects a leak in your evaporative emission system.
This is another powertrain problem, and you may receive a warning light with this problem. You receive the P0411 code when your OBD II system detects that air is not flowing correctly through your secondary air injection system. Depending on the vehicle, you may have a failed air hose, or may need to replace a thermostat. You should have both of these systems checked before doing any other repair work. When you read this error code, you may get "Unknown" or "Other" in the failing component category, but usually this is a powertrain issue.
This code indicates that you have a problem with your engine or engine cooling system. You receive this code when your OBD II finds that there is something wrong with the crankshaft position sensor. A circuit, and this sensor, monitors how fast the crankshaft is spinning. If you receive this error, you should get your vehicle serviced as soon as possible since you may have a problem with your engine or surrounding systems.
