When we recommend a ‘computer diagnosis’ it may sound critical. Everyone knows that critical vehicle issues can lead to large repair bills. However, AAA experts advise the public not to be too concerned as computer diagnosis is a regular practice for finding problems on today’s microprocessor-controlled automobiles.
“If we suggest that your car has a computer diagnostic, don’t be surprised. This is the best and most cost effective way for an auto technician to diagnose problems,” says John Nielsen, director, AAA Automotive Engineering and Repair. “Make sure you request that the auto repair garage explain what will be done to your car before you authorize them to do the work as ‘computer diagnosis’ is a generic term that covers a range of proceedures.”
To help car owners understand computer diagnosis, AAA Automotive Engineering provides the following info. Our engineering team’s goal is to help motorists understand the language of auto repair.
- Vehicle electronic control systems “know” and monitor the parameters of every one of your car’s component. When the Powertrain Control Module (PCM), the component that controls the powertrain recognizes feedback that is outside normal limits, or fails to see correct signals, it stores a Diagnostic Trouble Code (DTC).
- To access your automobile’s DTC, your auto mechanic connect a “scanning” device to a Diagnostic Link Connector typically located in the driver’s side of the instrument panel. The scanning tool shows the mechanic all stored codes. That is the beginning of the computer diagnosis.
- DTCs don’t tell a auto mechanic if a part is bad, they only report that the PCM has seen something that was outside normal parameters. The resulting problem may be a part. It could also be a problem with the circuit’s electrical wiring.
- Sometimes, DTCs record issues when there is nothing wrong in the electronic system. This could occur when a mechanical problem occurs. That could include an engine vacuum leak which cause system components to generate signals outside the normal range.
- To isolate the problem, the mechanic first identifies a problem using the DTC. He must them perform other tests to verify the issue. These tests can include mechanical checks, like engine compression, to in-depth electronic diagnosis. A procedure often uses a special diagnostic tool to read the electronic control system data network and watch real-time signals from electrical components.
The ability of the mechanic to select the proper additional tests needed and accurately interpret the test results and computer data comes from extensive training and experience. Today’s mechanics use computer diagnosis in the same way a surgeon uses medical tests. By using both test results with his expert knowledge, he is able to provide accurate diagnosis.
Please feel free to talk to Leon or anyone else at Diversified Automotive about any question you may have about the repair of your automobile.