Can I get diagnostic codes without a scanner tool?

Ron's Question: "Can I obtain diagnostic codes for my 2003 Chevy Silverado without the use of a scanner tool? I recall that earlier year vehicles could somehow get the engine light on the instrument panel to flash the codes."

No. In the eighties, when diagnostic trouble codes were first being used by a large number of manufacturers, each had it’s own code system, and they were usually short 1 or 2 digit fault codes which could easily be “flashed out” on the instrument panel. Since the introduction of OBDII, mandated by the federal government for all vehicles sold in the U.S. as of 1996 model year, these codes have become much more complex, usually five digits beginning with a letter followed by 4 numbers. The good news is that the new codes are mostly universal; for example, a code “P0302” will mean a cylinder #2 misfire on most vehicles. The bad news for do-it-yourselfers is that you can no longer get the codes to flash out on the dashboard, and even if you could, the code does not diagnose the cause of the problem, it simply tells the trained technician where to begin looking. While it is possible to purchase a generic code reader, we recommend a AAA Approved Auto Repair shop to properly diagnose the cause of the fault codes and recommend repair options. Don’t be fooled by a parts store offering “free diagnosis” of OBDII fault codes… you get what you pay for.