We repair transmissions for cars, trucks fleet and service vehicles

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.

More than half of our customers with transmission problems don't need a new transmission or a transmission rebuild. Components external to the transmission are often the fault. It can be a sensor, linkage, a cable, a vacuum hose, a vacuum control valve, a throttle control or one of many other possibilities. The failure of any of these components can cause a transmission to behave as if it has failed.

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 our technicians 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 our facility and have us drive it with the equipment installed. Our expert transmission technicians know how to locate and repair or replace external parts as well as any internal transmission issues you may have. When it comes to transmission repair, you can trust that our transmission experts aren't fooled by external components. Today's transmissions are very complex and without through training, a mechanic can only recomment a complete replacemenmt because they don't have the expertise to work on internal transmission parts.

Sadly, they recommend replacements that don't correct the issue because they didn't replace the actual offending external component. Unnecessarily, you pay the price in both time and money.
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Certified Transmission - Certi-Care Evaluation

Certified Transmission offers an Inspection of your transmission problem at all our San Diego County transmission shops.Let us explain what we are going to do when we perform our Certi-Care Evaluation:

First, we are going to scan your vehicle's computer to check for service codes.

Second, we are going to verify your concern and perform a road test as long as your vehicle is drivable.

Third, we will also do an under car check looking for any leaks or incorrect adjustments. When we are doing the under car evaluation we look for not only transmission leaks/transfer case/cooler lines etc., we will also advise you if their is something else we see or do not do see. We also check the differentials and power steering fluids. When looking for improper adjustments we want to make sure that something simple is not the causing the problem.

Over 66% of the vehicles we check out do not need a major repair.

The Certi-Care Evaluation Shield represents our commitment to your safety and is performed for our valuable customers. To request an automotive repair or service complete the form below. Once submitted, we will receive an email notification and will reply as quickly as possible - usually the same day. You can call us, mail us, or email us. Please fill out the following form to email us. If you provide us with your phone number, a professional transmission expert will be happy to call you.

Certified Transmission California has many conveniently located transmission Diagnostic and Installation Centers throughout San Diego county. We are transmission experts and have been providing full transmission service since 1978.

Whether you are considering a used, rebuilt, remanufactured, or factory transmission - we have a huge inventory of rebuilt transmissions and automatic transmission parts, we can ship out of inventory, repair or rebuild transmissions fast.

All of our centers offer an expert diagnosis. This saves our customers a lot of money. So often, people come to us thinking they have a transmission problem when they don't. Why risk a wrong diagnosis? Get it right from the experts.

We listen and respond to customer feedback. We appreciate comments, questions and feedback from our customers or customers-to-be.
Certified Transmission San Diego
229 South Coast Highway
Oceanside, CA 92054
888-319-2220 Toll Free