Automatic Transmission Computer Diagnostic Problems

Automatic transmission diagnostic problems surface in many different forms, including dashboard indicator lights, slipping or harsh shifts, poor performance, and strange noises. Because many transmission problems can be easily corrected, an accurate diagnosis is very important. Nobody would want to pay hundreds of dollars on service that doesn’t fix the problem or thousands of dollars on a rebuilt or replacement transmission that could’ve been inexpensively repaired. If your transmission is slipping or has other problems and you are looking for high quality information with which to educate yourself, and you have come to the right place. If you plan on taking your car truck to a mechanic, here’s some important information about choosing a transmission service and repair shop. It is common knowledge that code scanning tools are essential when diagnosing automotive engine and transmission problems. However, there are many other diagnostic tools available for effectively troubleshooting electronic and computer control issues. All transmission service facilities should have these specialized tools, unfortunately, most do not. An fully-equipped shop for diagnostic repair service of automatic transmissions in Maryland is located in Laurel.

A Transmission Code Scanner Does Not Perform an Accurate Diagnosis.

Scanning transmission codes is an essential first step when performing a diagnosis. The information provided aides in determining the cause of the problem. Transmission problems can be divided into two categories: electrical circuit and all other, which include hydraulic and mechanical issues. All problems can produce error codes, but using the literal meaning of a code definition will usually result in a misdiagnosis. The only error definitions that describe the nature of a malfunction with any level of reliability are electrical circuit code definitions, other definitions should never be taken at face value.

Diagnosing Sensor Codes and Adaptive Shift Strategies

95% of the vehicles on the road today have transmissions that are computer controlled. Data is collected from various sensors on the engine and transmission, and calculations are made to control shift timing and firmness. Transmissions no longer use vacuum modulators, governors or kick down cables to control operational attributes. The functions of these elements are now handled by electronic speed sensors, throttle position sensors, and mass air flow sensors. Code scanners will usually pick up on electronic speed sensor malfunctions, but they do not reliably detect problems with mass air flow sensors or throttle position sensors. Most of this equipment is useless when solving complex computer controlled problems. Many of today’s error codes are the result of problems with adaptive shift learning, which standard code scanners cause someone to easily misdiagnose. There are a few specialized automatic transmission diagnostic test tools available that allow technicians to operate the transmission independently of the vehicles computer control module. These can also monitor all signals given by the computer to the transmission. These products allow the technician to more quickly diagnose complex problems between the computer, automatic transmission, and car or truck wiring harnesses.

Sporadic Transmission Diagnostic Problems

Transmission problems can occur intermittently and therefore some electrical problems might be difficult to diagnose. It is often beneficial to have a specialized electronic diagnostic interface attached to the transmission when the problem occurs. This means you would have to drop the vehicle off at a repair facility and have them drive it with the equipment installed. If the transmission problem only occurs after driving the car or truck for a couple hours, you should be prepared to pay for at least two hours of diagnostic time. Because some technicians may cheat you on the amount of time they spend on your vehicle, it would be a good idea to insist the vehicle be driven at least a set number of miles. The best scenario would be for you to arrange to ride in the car or truck with them so there is no misidentification of the problem if it occurs. Any shop that denies you this opportunity should probably raise a red flag