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On Board Diagnostics for Bloomington Motorists

July 13, 2022

Some Bloomington vehicle owners wonder why Tuffy Bloomington and other Bloomington auto repair shops charge a fee for vehicle diagnostics.

Receiving a diagnostic charge at Tuffy Bloomington for a tricky automotive problem shouldn't be a surprise. In the Bloomington 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 Bloomington diagnosis may be much more involved.

Much of the Bloomington 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 Bloomington 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 Bloomington 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 Bloomington customers. The service advisor makes a list of the most likely causes and begins tracking down the source of the problem. This takes time.

Bloomington 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 Bloomington wants to figure out what's wrong with your vehicle and get you back on the road as quickly as possible.

Tuffy Bloomington
1505 East Vernon Avenue
Bloomington, Illinois 61701
309.662.0537

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