how do you diagnose an automatic transmission problem

Diagnosing faults in automatic transmission

• Reliability. The main reason for this greater relibility is the fact that the gears are engaged smoothly by the operation of internal clutches and brake bands under automatic control, so ...
• Simple checks. ...
• Fluid transmission level and condition. ...
• Adjust the parking cable. ...
• Reset downshift cable. ...
• Test automatic inhibitor switch. ...
• Adjust control linkage. ...

Full Answer

How to tell if your automatic transmission is bad?

How to know if the transmission is bad?

• The transmission doesn't switch gears. If you noticed that your transmission is not able to switch gears, this is a clear indication of a bad transmission.
• Strange burning smell. ...
• Hearing noises when neutral. ...
• Gear slipping. ...
• Transmission fluid leak. ...
• Check engine light is illuminating. ...
• Hearing a strange sound like humming. ...

What is so bad about an automatic transmission?

Other common problems have included owners reporting a sudden loss of acceleration and transmission overheating. Drivers complain of jerking, slipping, and shuddering as the belts can suffer excessive stretching and wear or complete failure.

How long does it take to diagnose a transmission problem?

The actual diagnosis itself may only take a couple of hours to perform. Perhaps as little as one hour. Even though the diagnosis may be that fast, it's also possible that the mechanic will ask you to come back within half a day, or even a full 24 hours later.

Why is automatic transmission so hard to repair?

What causes automatic transmission shifting hard?

• Transmission Fluid: You have to check the transmission fluid. ...
• Vacuum Problems: Automatic transmission hard shifting might be due to problems with the vacuum lines. ...
• Sensor Problems: These days, vehicles are equipped with a wide assortment of sensors that include those which control when and how the transmission of the car shifts.

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What should be the first step in diagnosing an automatic transmission problem?

The first step in determining your transmission problems consists of the technician connecting the diagnostic equipment to your vehicle's on-board computer. This will produce a code stating where the problem lies.

What is the most common cause of automatic transmission failure?

At the top of all auto repair experts lists for causes of problematic transmissions is low transmission fluid. Usually caused by a leak somewhere in the system, low or contaminated fluid makes it nearly impossible for the transmission to automatically shift gears and run smoothly.

What are the top 5 signs of transmission problems?

Top 5 Signs of Transmission TroubleGrinding Noises. One of the more common symptoms of transmission trouble is a grinding noise that occurs during shifting. ... Burning Odor. Transmission fluid often smells tart or slightly sweet. ... Transmission Warning Light. ... Delayed Shifting. ... Transmission Fluid Leak.

How do you troubleshoot an automatic transmission?

Step 1: Try to find your problem first. ... Step 2: Check your transmission fluid. ... Step 3: Check your on-board diagnostic codes. ... Step 4: Read a repair manual or website. ... Step 5: Bring it in to a professional mechanic.

Can a blown fuse cause transmission problems?

But a blown fuse No. 38 becomes a likely candidate causing a loss of power to the transmission solenoids.

How much is it to fix a transmission?

Average transmission repair costs range from $300 to $1,400. For example, if your manual transmission needs a new clutch, you can reasonably expect to pay around $800 to $1,500. On the other hand, transmission replacement is one of the most expensive repairs you can get. Replacements can range from $1,800 to $3,400.

Will my check engine light come on if my transmission is bad?

Yes, transmission problems can cause your check engine light to come on. Your automobile's main computer, the engine control module (ECM), talks with system sensors to make sure everything is okay. If the transmission sensors report a problem, the ECM will turn on the check engine light.

What happens when your automatic transmission goes out?

Automatic transmissions usually begin to buzz, whine or hum when they are failing, while a manual transmission will sound (and feel) like the gears are grinding. Smells and leaks. Cars leak a variety of fluids, which is why you need to be able to recognize the different types of automotive fluids.

Can you drive with transmission problems?

Is driving with a faulty transmission okay? Short answer: no! The only thing you should do if you think you have a faulty transmission is go for a quick jaunt to your local mechanic. If you have a bad transmission it's only a matter of time before your vehicle literally won't be able to drive anywhere.

Can you fix a transmission without replacing it?

So, yes, there are some car repairs that can be done without replacing the part in question, like electrical components of your transmission, or the external components like bushings and shifter cables. Some bad news for you: everything with your car's transmission cannot be fixed from the outside.

Can you test an automatic transmission out of the car?

You can test the transmission by putting it through the gears while turning the input shaft and examining the output shaft for proper rotation. You cannot test the clutch while off the car.

What causes an automatic transmission to not go into gear?

Transmission won't engage or stay in gear If when you put your vehicle into gear and it won't move, this may be a problem with low transmission fluid due to a leak, the shifter, shifter cable, or it could even be a problem in the valve body of your automatic transmission.

What causes an automatic transmission to not go into gear?

Transmission won't engage or stay in gear If when you put your vehicle into gear and it won't move, this may be a problem with low transmission fluid due to a leak, the shifter, shifter cable, or it could even be a problem in the valve body of your automatic transmission.

Do transmissions fail suddenly?

Luckily, transmission failure doesn't usually happen without warning. There are several warning signs that your transmission's going out.

What would cause automatic transmission not to shift?

Why the Transmission Won't Shift Gears. One reason why an automatic transmission isn't shifting into gear has to do with the fluid. If it's not at the right level or the incorrect type has been used, then it'll affect the gears. Another big reason has to do with the ECM possibly going bad.

What happens when your automatic transmission goes out?

Automatic transmissions usually begin to buzz, whine or hum when they are failing, while a manual transmission will sound (and feel) like the gears are grinding. Smells and leaks. Cars leak a variety of fluids, which is why you need to be able to recognize the different types of automotive fluids.

How to determine transmission problems?

The first step in determining your transmission problems consists of the technician connecting the diagnostic equipment to your vehicle’s on-board computer. This will produce a code stating where the problem lies. Following this, the vehicle should be taken for a test drive so that the technicians can monitor the transmission’s behaviour in real-time. While more comprehensive and hands-on evaluations might still be necessary, today’s technology is an integral tool in determining the best starting point for further investigations.

What technology can communicate with your car's computer systems to determine your specific transmission problems?

Today’s vehicles come equipped with complex computer systems. And modern diagnostic technology can communicate with your automobile’s computer systems to determine your specific transmission problems.

Why is diagnostics important?

Diagnostics is obviously a very important practice because without it, fixing any transmission problem would be complete guess work. You can have the most talented technicians in world trying to fix a problem, but if they don’t know what ...

Why is my transmission fluid leaking?

Sometimes it is simple enough to determine the problem. If you’re seeing transmission fluid underneath your vehicle after every time you park, you likely have a leak. But some problems, especially computer problems with computerized transmissions, can be especially tricky.

Is there a one size fits all transmission?

There is no one-size-fits-all solution to transmission problems, and anyone who says otherwise is either ignorant or a charlatan. To ensure your vehicle’s well-being –and yours– you should only trust certified experts to diagnose your transmission problems.

Why do automatic transmissions have faults?

Automatic transmission faults. Because of the large number of parts inside an automatic gearbox, some faults may be caused by more than one component. The first check should always be on the transmission fluid level and its condition — if it is all right, then you will need to check the other points shown here.

What causes transmission problems?

When problems do occur they are often caused by the external control linkages , or a low fluid level , and can often be dealt with without having to strip the transmission . Internal transmission faults generally call for specialist equipment and knowledge and are best left to a service engineer - after you have checked to make sure that the problem really is internal.

How to check transmission fluid level?

Try standing the car over some newspaper laid out on the ground . Start the engine and operate the transmission lever a couple of times. Any drips will show up on the paper and their position will give you a good idea where the fluid is coming from. If the level is all right, you should check the fluid condition. The condition of the transmission fluid can often provide a useful guide to transmission condition. Put a smear of fresh fluid on some white kitchen paper to give a comparison and then use the dipstick to obtain a sample of the fluid from the transmission, again smearing it on paper.

What does it mean when your transmission fluid is dark brown?

Dark brown discoloration shows that the fluid has been overheated, while the presence of black specks points to heavy wear of the internal clutches and brake bands and an internal investigation will probably be needed — especially if your other tests show the transmission is not working properly.

Why is my transmission causing a bumpy start?

Bumpy starts and gear shifts, for example, can be caused by a high engine idle speed .

How to keep engine revs up?

With the engine running and both the engine and transmission properly warmed up apply the footbrake firmly, select the lowest gear and fully depress the accelerator pedal so that the engine revs up - keep it going until the revs stop rising. Using an accurate rev counter, make a note of that engine speed (called the stall speed).

Why is my automatic gearbox not working?

If that seems to be all right, you need to do a test to discover whether the problem is in the gearbox, the torque convertor or the engine. A general lack of performance with poor acceleration and bad hill starting can be due ...

How to know if your automatic transmission is bad?

Try to find what the problem is firsthand before bringing it into the shop. Take look under your car for any leaks, or shift between gears to check for any issues or gear slipping. The chart above contains common automatic transmission problems and what causes them.

What to do if your transmission is not working?

If none of the other steps have helped you figure out what’s wrong with your automatic transmission, have an expert transmission specialist help troubleshoot your vehicle. For some issues it is just best to go to someone with more experience who has most likely seen the symptoms you have been trying to figure out. Even if you are able to troubleshoot your automatic transmission issues, it’s often best to bring your vehicle in to a professional in if the problem is too complicated to fix yourself. If you’re looking for the best transmssion mechanics near you, look no further than one of our AAMCO Utah Transmission and Total Car Care centers . Schedule an appointment online today!

What to do if transmission fluid is low?

If the fluid levels are low, you should add more transmission fluid of the correct type as specified in your vehicle’s owner’s manual. You may need a complete fluid and filter change if your transmission fluid is contaminated, black, or burnt. Check the handy reference chart below for the health of your transmission fluid.

Where to schedule transmission inspection in Utah?

Bring your vehicle in for a full automatic transmission inspection — schedule an appointment at your local AAMCO Utah location. We will take care of your car and get you back on the road safely in no time.

What to do if your car does not come up with a code?

If the car does not come up with any codes or there isn’t a solution for the code then you’ll want to check out a repair manual or website for your vehicle’s specific make and model. Repair manuals tend to how much more in-depth details about your vehicle and how to fix them, although you’ll need to pay for them to access that info. There are some auto repair websites online that offer free information or have an ask a mechanic forum.

Can you get your transmission fixed at Aamco?

If you know the symptoms of specific transmission issues, you can avoid wasting time and money getting the wrong things fixed. When it comes to automatic transmissions, you want to get them fixed as quickly as possible at the lowest cost of course. Here are a few steps that will help you diagnose your transmission problems, their causes and give you a solution for each problem. AAMCO Utah’s expert mechanics can give your vehicle a full automatic transmission inspection to accurately diagnose your transmission problems. Schedule an appointment online today at an AAMCO Utah location near you.

Can you fix an automatic transmission without tools?

You should follow these basic steps before you bring your car to your local repair shop so that you can most accurately and cost-effectively troubleshoot your automatic transmission. When it comes to transmissions, without the right tools, many problems will be too advanced to fix yourself, but diagnosing the exact cause can make repairs easier for you and save you money at the shop.

How to tell if transmission is bad?

The most common symptom of a bad transmission is shifting issues or no movement at all when you engage the Drive or Reverse gear. If you hear banging and clunking noises when changing the gear, it may also be a sign of a worn transmission.

What happens if your transmission isn't working?

When your transmission isn’t functioning the way it should, it’s not uncommon for it to revert to more basic functions or lose gears entirely. If that happens, performance is going to suffer as a result.

Why does my transmission make a noise when shifting?

As the gears shift, you hear lots of banging and clunking noises, which you know aren’t normal. You hear those signs because somethings moving around inside your transmission that shouldn’t be.

Why is my transmission slipping?

A slipping transmission is a very common cause of a bad transmission. If you notice that your transmission is slipping into the wrong gear before jumping back into the right one, that’s a sign of an underlying problem.

What is transmission in a car?

The transmission is your vehicle’s power delivery unit. While your engine produces the power, your vehicle won’t move an inch until your transmission delivers it to the wheels. There are tons of gears inside your transmission, and each one excels at different functions.

What does it mean when your transmission smells like it's burning?

When something smells like it’s burning inside your transmission, something is burning inside your transmission. You might be able to fix the problem with a transmission flush, but if the problem persists, you’re going to need a rebuild or a new transmission. 5.

What is the purpose of gears in a transmission?

There are tons of gears inside your transmission, and each one excels at different functions. These differing gears optimize power output for different functions, from low-speed driving to accelerating and optimizing fuel efficiency.

What is the best tool to diagnose transmission problems?

Scan tools offer the best bet for diagnosing automatic transmission problems. This screen displays the status of the various transmission shift solenoids.

What are the gears in an automatic transmission?

Modern automatic transmissions contain multiple planetary gear sets composed of sun, planet and ring gears. As you might imagine, the sun gear is ­located at the center with the planetary gears ­revolving around it. The ring gear provides the outer gear set.

How does a clogged catalytic converter affect transmission performance?

Transmission performance will be affected by ­engine performance . A clogged catalytic converter can, for example, affect MAF and/or Baro inputs to the ECM, which, in turn, affect the calculated ­engine load, which is a primary TCM input. The performance of a seemingly insignificant engine part, like a thermostat opening too early, can actually prevent torque ­converter lockup. As more gear ratios are added, engine-operating parameters become increasingly important for providing correct automatic transmission control. You should also be aware that a few high-end Euro ­imports might integrate transmission controls with the vehicle security ­system, which can interfere with parts availability for non-authorized repair shops.

How does a transmission work?

Early mechanical/hydraulic transmission controls use inputs from the throttle linkage and a mechanical governor mounted on the transmission output shaft to automatically select gear ratios. To illustrate the basic concept, hydraulic pressure from the governor pushes the 1-2 shift valve from 1st gear to the 2nd gear ratio as vehicle speed increases. In contrast, opening the throttle will increase throttle valve (TV) oil pressure on the opposing side of the shift valve, which then forces the 1-2 shift valve back to the 1st gear ratio. The remaining shift valves work in a similar manner. Many early-model automatic transmissions also modified shift points by adding a vacuum modulator, which uses intake manifold ­vacuum to fine-tune throttle and governor pressures. As with modern transmissions, the manual control lever can be used to override the automatic shift controls to meet specific driving conditions.

What does blackened transmission fluid mean?

Blackened fluid usually indicates a slipping clutch or band.

What is the default shift on a transmission?

In default mode, the transmission will typically shift 1-2 and then remain in 2nd gear. In default, forward gear operation is normally controlled by a one-way roller clutch, which prevents transmission lockup by ­allowing the transmission to “free wheel” during deceleration.

How to detect voltage loss in ignition switch?

A voltage loss through the ignition switch can be detected by measuring the ­voltage drop ­between the underhood fuse box B+ terminal and any of the fuses activated by the ignition switch.

Is there a one size fits all transmission?

There is no “one-size-fits-all” solution to transmission problems , and anyone who suggests otherwise is misinformed, or they may be trying to take advantage of you. Most importantly, they may be compromising your safety. We Will Never Compromise Your Safety.

Is digitization of cars a high tech thing?

The digitization of your car goes far beyond wirelessly connecting your smartphone to a sound system. Diagnosing transmission problems in modern vehicles is a high-tech affair

What are the problems with a transmission?

The most common transmission problems are leaking seals, a worn-out clutch, or old transmission fluid. Faulty components inside the transmission like bad shift solenoids, bad transmission bands or a faulty torque converter are also very common.

What are the most common transmission problems?

The most common transmission problems are leaking seals , a worn-out clutch, or old transmission fluid. But while these are the most common problems, they aren’t the only ones you need to keep an eye out for. We’ll give you an in-depth dive into each issue below. 1. Leaking Seals.

Why can't I get my transmission out of gear?

When your transmission can’t get into or out of a specific gear, it can be a litany of problems. Start by hooking up an OBD II reader to your vehicle and seeing if the TCM generates any codes. If this is the case, your problem might be as simple as a faulty sensor or solenoid.

Why is my transmission overheating?

Overheating Transmission. While an overheating transmission is a sign of a deeper problem, it might be the only thing you notice. There are tons of reasons your transmission might overheat. From jammed gears to old transmission fluid, you’ll need to thoroughly troubleshoot your transmission to find out what’s going on.

What happens when transmission bands break?

But when these bands start to break, you’ll find that your transmission simply doesn’t have gears that it should.

How to tell if a transmission leak is coming from the bottom?

If it’s coming from the bottom, it’s likely the transmission pan, but it’s likely a front main if it’s coming from the front.

What happens when oil leaks in transmission?

Just like your engine, oil fills your transmission to keep everything running smoothly. That transmission fluid is held inside through gaskets and seals, and as your transmission ages, those gaskets and seals can wear out. If this happens you’ll get a leak, and you’ll need to make repairs.

Overview on Automatic Transmission Problems and Solutions

The automatic transmission is that system in your car that allows you to change gear at different speeds. Under normal driving conditions, it does not require any form of control from you in changing or shifting gears.

Solution: Replace the shift cable

The transmission fluid is essential for lubricating the parts of the transmission to ensure that it keeps running. When the fluid is low it can cause the transmission to slip or even overheat and build friction during use. To know when to top the transmission fluid, it is important that you check the level routinely.

What Causes Delayed Shifting Automatic Transmission Problem

Delayed shifting is when a shift does not happen when it is supposed to. Having to wait for the transmission to go into gear can be frustrating.

Why the Delayed Shifting When Accelerating

Whether you are speeding up or just moving, when the automatic transmission doesn’t shift when it is meant to then there is a problem. If you experience delayed shifting when accelerating then there is a problem with either the valve body, the ECU, or the solenoid.

Reason Why the Automatic Transmission is Making a Rattling Noise

Noise; that’s one sound no one wants to hear, especially when it’s coming from their car. They are however an indication that something is faulty and needs fixing. So is the rattling sound being made by the automatic transmission? It is not just there to annoy you but to alert you.