A customer came to HomeTowne Auto Repair & Tire, because their vehicle’s check engine light had turned on.

They stated that they weren’t having any problems when driving the car, but the light had turned on a couple days earlier. 

The check engine light coming on is one problem that can be addressed through diagnostic testing.

You may have heard of this process if you’ve had something going on with your car. 

Diagnostics might sound unnecessary, but it’s a very helpful and important part of getting your vehicle back on the road.

The importance of performing diagnostics

Diagnostic testing goes beyond reading a code or looking over a vehicle.

Anybody can take a car to have a code read, or check it out themselves with a flashlight. Diagnostic testing enables technicians to dig deeper into the problem.

Codes are like zip codes — they tell us where in the neighborhood you’re supposed to be. However, further investigation is necessary, because they can mask other issues.

For example, there could be a code for a catalytic converter and we could say, “OK. We read the code. Replace it.” But the code could really be caused by oxygen sensors that aren’t reading correctly.

Through diagnostic testing, technicians are able to determine the actual reason for a failure or problem, which can help you save money in the long run.

Diagnostic testing process

The diagnostic testing process begins by gathering relevant information from our customers. 

This includes any sounds, a problem (or problems) they are experiencing, when they are noticing an issue, and any incidents that may be connected with it.

Providing as much information you can helps us narrow down the investigation and come up with a solution more quickly.

Once all of the details have been collected, our Woodbridge mechanics will conduct a courtesy inspection, where they ensure that nothing seems amiss on the vehicle.

Then, the technicians try to encourage the problem to reoccur. This includes performing a test drive, which helps them determine if there are any odd noises or the car isn’t running correctly. As the procedure continues, we hope to zone in on a certain part of the vehicle and, eventually, the cause itself.

While diagnosing a noise or behavior, we also do our own research using Technical Service Bulletins (TSBs) – in case it’s a common problem with this type of vehicle. Additionally, our employees utilize diagnostic equipment with built in diagnostic capabilities and other resources that are tailored to auto repair shops.

It can sometimes be difficult to pinpoint the problem, especially if what the driver is experiencing isn’t occurring all the time. 

For example, the A/C on a Chevy Colorado we’re working on next week will randomly stop blowing air. That could be caused by a few different problems – it may have a bad blower motor or the wiring may need to be replaced.

So, performing diagnostics can take time. You may even need to pick up the vehicle and bring it back when the problem starts happening more frequently.

HomeTowne Auto Repair & Tire is an authorized Michelin and BFGoodrich tire dealer located in Woodbridge, Virginia. Automotive repair services are performed on all makes and models, including oil changes, brakes, alignments, inspections, and computer engine diagnostics.