Back to all

On Board Diagnostics for Joliet Motorists

October 7, 2018

Some Joliet vehicle owners wonder why Tuffy Joliet (South Plainfield) and other Joliet auto repair shops charge a fee for vehicle diagnostics.

Receiving a diagnostic charge at Tuffy Joliet (South Plainfield) for a tricky automotive problem shouldn't be a surprise. In the Joliet area, automotive diagnostics can cover quite a range. If you hear a noise in your vehicle brakes when you slow down in rush-hour traffic on a busy Illinois road, you pull off at the next off-ramp and take a quick visual check. That is usually enough to know what needs to be done. If you're having an intermittent problem with your vehicle engine, however, a Tuffy Joliet (South Plainfield) diagnosis may be much more involved.

Much of the Joliet driver's confusion comes when the problem involves the Check Engine light. The Check Engine light comes on when the engine management computer has sensed a problem.

There's a common misconception among Illinois drivers that the trouble code tells the Tuffy Joliet (South Plainfield) technician exactly what's wrong. They wonder why there is a diagnostic charge because the scanner quickly gave the diagnosis.

In reality, it is not that easy and straightforward. The computer monitors many sensors throughout the vehicle. When one of these sensors has a reading that's out of parameters, the computer will record a trouble code and turn on the Check Engine light.

The vehicle computer's trouble code just tells the Tuffy Joliet (South Plainfield) technician what engine parameter is out of range, not what's causing it. The technician needs to determine the underlying problem that's causing the malfunction.

There are many problems that could cause a troublesome sensor reading for Tuffy Joliet (South Plainfield) customers. The service advisor makes a list of the most likely causes and begins tracking down the source of the problem. This takes time.

Joliet service centers subscribe to databases that document possible causes for all the possible trouble codes. The databases outline procedures for confirming a diagnosis and provide the documented repair. These  databases are specific to each vehicle and engine combination.

Some diagnoses are quick and easy. Others are more involved, time-consuming and difficult. Of course Tuffy Joliet (South Plainfield) wants to figure out what's wrong with your vehicle and get you back on the road as quickly as possible.

Tuffy Joliet (South Plainfield)
2031 SR 59
Joliet, Illinois 60586
815-436-1829

More articles from Tuffy Joliet

You Are the Fluid Detective! (Leaking Fluids)

October 12, 2025

When you see some liquid sitting underneath your vehicle, your mind starts churning. Is that normal? Is that something serious, or did I just spill my drink? Heres a quick list of what those fluids look, smell and feel like, as well as what they might be. No, we dont recommend you taste them to ... More

Reaching the Braking Point (Brake hose replacement)

October 5, 2025

If you notice your brakes arent working like they used to, thats the kind of thing thats important to have checked out soon. Thats because your brakes are extraordinarily important to the safe operation of your vehicle. Sometimes you feel like your brake pedal is feeling a little soft or its lo... More

Smooth Operator (Shocks and Struts)

September 28, 2025

Few of us ever drive somewhere without encountering some pretty rough roads, and it's amazing how well our vehicles are able to smooth out the ride. Thank your shocks and struts. The two parts are similar. Some cars have shocks in the rear, and struts in the front. Others have struts all around... More