1990 Mercedes-Benz 420SEL General Diagnosis Cost

As a customer with an uncommon vehicle issue, you may find it is best not to speculate on the issue, and simply tell the technician "fix it". Any information you can provide the technician is helpful, and the technician will go into diagnosing an unknown issue, also known as general diagnostics.

When a vehicle comes in for repair, and there is an obvious fault, such as "the wheel bearing is grinding or the brakes squeal at stop lights", these problems are generally not diagnosed, as the technician already understands the problem after inspecting the vehicle. Problems such as, "I hear a thump sometimes" or "my car feels like I'm in an airplane", are more vague, and until the technician knows what system is at fault, or verifies the existence of a fault, the process used is general diagnostics. With general diagnostic procedures, the servicing will systematically move through the systems of a vehicle until the fault is uncovered.

Like we noted in the last section, general diagnosis symptoms are the most vague of the bunch. There are several diagnostic spectrums, electrical diagnosis, drivability diagnostics, engine diagnostics, transmission diagnostics, and the list could continue for about 5 or 10 more spectrums of diagnostics. The most important take-away here, is that general diagnostics are diagnostics that have no other spectrum in which they fit, or the problem is unknown. This means that any vehicle left outside of a repair facility with the keys and an authorization to perform diagnosis will be diagnosed under the general diagnosis spectrum.

As far as general diagnostics go, the answer is maybe. If it is uncertain if a vehicle is safe to drive, take the safe route and have it towed. If the issue is just a random noise, or the check engine light pops up, driving the vehicle is normally not an issue. However, if the vehicle is unsafe to drive, difficult to keep under control, or responds poorly to driver input, the vehicle should be sent to a professional technician.