Computer diagnostics — what are they? how are they done, and what do they cost. Most cars have some form of a computer to operate the performance system. Computers have evolved in recent years, so there are any number of operating systems running from primitive to very high tech depending on the age of the car.
What are computer diagnostics? Computers generate signals called data streams. These streams of data flow through the operating system of the car at all times, constantly adjusting and re-adjusting the engine. Diagnostic computers that are interfaced with the car’s computer read the data streams flowing through the system. When a problem with a computer-controlled car crops up, it shows up either in the form of a drivability problem or a lit check-engine light on the dashboard. The problem could be in the form of a bad sensor, malfunctioning electrical or mechanical component, or damaged wiring and plugs. The system is designed to generate a trouble code when it “sees” a problem in the system. This code is supposed to lodge in the onboard computer’s memory for retrieval at a later date, aiding in diagnostics. The shop must have access to information either in book form or online to decipher what the codes mean and how to go about diagnosing the particular problem area. Sounds simple right? Hook the car up to “Da Machine” and it will tell you what’s wrong — hold on, not so fast, it’s not that easy! What happens when there is no evidence of a trouble code stored in the car’s computer and no check-engine light is lit, but a drivability problem still exists? This is where the men are separated from the boys in the world of onboard computer