Real-world reflashing: Cutting through the smoke and mirrors

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Real-world reflashing: Cutting through the smoke and mirrors

All vehicles reflashed by Craig Truglia and Adam Varney. Contributions made by Kevin Quinlan and Alex Portillo.

There are a lot of myths out there regarding reprogramming modules on today’s vehicles.

It’s easy! No it’s not.

J2534 reflashers can reprogram all manufacturers’ modules and easily work as the factory scan tool for Toyota, Volvo, BMW, etc. Not exactly.

It’s a low-risk, high-profit proposition. No.

30% of vehicles require a reflash! Not really....

Out of every 100 drivability problems we get in our shop, maybe one out of that 100 is fixed by a module reflash. In the real world, you probably are just like us. We rarely need a reflash for anything, but we do run into it.

So, we cannot avoid reflashing. This begs the question: what are you going to do about it? Send it to the dealer or mobile tech? Do it on your own?

Here we are going to cover three things so that you can take the best course of action for your business.

1. Making reflashing profitable.

2. Buying the right tools.

3. How to actually reflash, step-by-step.

Before you spend all the money on the tools and hours frustrating yourself, take a few moments to take in what we will cover here.

Making reflashing profitable. Most shops send the car to the dealer. They have it towed or have “the kid” drive it there. This is certainly a workable system. It requires no investment in tools and has no liability. Most dealers charge $50 to $100 to a shop. I know shops that get it for free, which makes me wonder what I’m doing wrong... no dealer bends over backwards to give me anything for free; but I digress.

The cost of having reflashing done this way is threefold. First, the tow or the kid’s time is not free, and the cost goes up with the distance to the dealership. Second, you are now working around the schedule of the dealer, which makes the process less timely. Third, this long process has its expense passed onto the customer, who is not impressed by the delay and your lack of ability in this department.

To me, perception is everything. I like to be the bakery where I bake my own bread. So, we find it more cost effective to pay a mobile tech or reflash on our own. We use an Autologic on European vehicles (and that’s so easy, you can do it without any training) and a Drewtech Cardaq-Plus on American and Asian vehicles. The mobile tech fills in any other gaps where the J2534 box does not lend itself well to reflashing (Nissan, Mazda, Mitsubishi, etc.). [See Figure 1.]

So, the logic behind why you should do your own reflashing is simple enough, but do you have the two key ingredients: (1) $2,500 for tooling and, (2) the right tech-savvy technician to do the reflash.

Those two ingredients also need to be profitable for you. If not, venture no farther into the world of reflashing and revisit the topic when the equation works in your favor.

Buying the right tools. This is absolutely essential, but this is not going to be an advertisement for any tool company. We are going to cover what you absolutely need to get started.


1. Battery maintainer.

In the real world, you take on risk using a regular battery charger or battery saver when doing a reflash. Why? Modules will turn on loads during a reflash, which require a certain amount of amperage (over 70 on some BMWs and Volvos). If you do not have enough power during a reflash, you just bought yourself an expensive paperweight. [See Figure 2.]

Why not simply use a charger? Battery chargers have an uneven flow of energy with high A/C ripple. True, it is possible to reflash this way. We once reflashed a 2009 BMW X5 with a J-Box and battery charger; but it’s a stupid thing to do. [See Figure 3.]

All newer vehicles, which are fast becoming the old vehicles that require service in your shop, will pull a lot of amperage during reflashing. So, you are going to have to shell out $300 to $1,000 for a battery maintainer/charger.

A battery maintainer is different than a charger, because it can supply a steady voltage and amperage with a very low amount of A/C ripple. Scott Manna of MB Automotive, who doubles as a nationally renowned instructor, has done a lot of testing on the popular battery maintainers out there. He found that the ATS ECharger and the Midtronics PSC550 (or GR8 for that matter) were two specific battery maintainers that really fit the requirements for what a battery maintainer should do. At my shop, we tested the Fronius and found it to be in the same elite class of battery maintainers. So, you have a list of three to choose from, and none of them are that cheap.

2. J2534 “J” Box.

Yes, you can buy a factory scan tool. It will work. If you are a European shop don’t even waste your time with a J-Box. It works terribly on Volvo and BMW. Just get an Autologic or factory equipment.

For the rest of us, we are using the J-Box. It does most of what we work on (Ford, Toyota, Hyundai, etc.), but it is definitely not easy. However, if you put the time into it, J2534 reflashing is a viable option.

So, which J-Box is best? They all pretty much cost the same, so stick with OEM-validated J-Tools. The two most commonly validated J-Boxes are the Ease and Drew Tech tools. Being that Ease now uses the Drew Tech Cardaq for their own tool, that narrows down the list a bit.

In my honest opinion, it is advisable to go right to the J-Box source instead of buying a reboxed Cardaq from someone else. For example, the Snap On J-Box most definitely does not work on Hyundai-Kia. It is believed that this is because a proprietary chip was added that the Hyundai OEM software does not like.

3. Laptop.

Any fairly recent laptop will do, but it must be 32-bit (not 64-bit) and a Windows XP or 7 Professional system. OEM programs simply do not work on 64 bit systems, and generally work only on Windows XP. Windows 7 Professional comes with an XP emulator which essentially allows the PC to be backwards-compatible to XP.

Consider making your laptop a reflashing-only tool. Do not add any unnecessary programs or scan tools to it. The more things that pop up and interrupt a reflash, the higher the likelihood of ruining a module.

Reflashing step-by-step

So, is reflashing as easy as some tool salesmen and instructors make it sound? No! But why not?

First, there are a lot of precautions one has to take when reflashing. This includes maintaining proper battery voltage, making sure not to kick any DLC or USB wires, and having one’s computer settings set so nothing pops-up in the middle of a reflash that can reset the computer and smoke the module.

Second, in the real world reflashing can be awfully hard to remember how to do. If all you had to do was reflash one vehicle that would not be the case. However, most of us work on multiple car lines and we do so few reflashes that it becomes mentally impossible to reflash in a timely and profitable way. Every manufacturer has different programs with their own little bugs to work out. It helps to take notes so you can consult them in the future.

Because space does not permit us to cover every manufacturer, we will just focus on Ford and Chrysler. Ford is notoriously hard to do and Chrysler the opposite. However, there is no reason that you have to buy a Ford IDS to reflash Ford as long as you do one important thing: follow directions.

Reflashing requires that you do everything in an exact way or it does not work. If you follow the following steps, you can reflash Ford.


The following is a case study on a 2005 Ford 500.

Having never reflashed a Ford using a J-Box, we anticipated a good learning experience (and not a profit) when we took on the job.

It took 25 hours from the time we started and when we were able to get it all to work. Needless to say, there are a lot of nuances that go into learning how to reflash a Ford using a J-Tool. I went through the pain so you do not have to.

1. Go to and log in.

2. Click on “Reprogramming” and scroll down on the bottom of the page that pops up and click on “Purchase.” After you purchase the software (covered in steps 3 and 4), you will return to this menu and then click on “Ford Module Reprogramming Application.” You will scroll to the bottom and click “Ford Module Programming.”

3. Everything is pretty self-explanatory until you hit the point where you choose to buy temporary access to Ford reflashing software. Be sure to click on the drop down menu next to term and choose “short term.” Chances are you will not be doing the quantity of reflashes to justify paying for a longer period.

4. Disable your pop-up blocker, or you will not be able to pay for the reflash subscription.

5. When you install the Ford software, there is nothing confusing about it besides the part in which you are prompted to enter your “User ID.” It is the same as the User ID you made to log into the website to begin with. NOTE: You will be required to enter this User ID again when you actually use the Ford reflash software.

6. After downloading the Ford reflash software, make sure all the drivers and software updates for your J-Box are up-to-date. This can take frustratingly long to do, and the more you are familiar with your J-Box the easier this is.

7. Start up “Ford Module Programming” and carefully read the following screen. If you do not, you will be subjecting yourself to additional frustration.

Seriously, read the directions here. You cannot skip over them and complete the Ford reflash process. Thankfully, the directions do not have any unnecessary fluff.

8. Follow steps one through five to enter in your “User ID” into the Ford software. Do not forget to click on the check box to the bottom right to progress to subsequent screens. When you are asked to enter your User ID be sure to CLICK TAB!!! It will be the only way you can type in your User ID. This really stumped me for a while.

9. Afterward, select your J-Box from the menu by following steps six through eight.

After choosing your J-Box from your drop down menu, click “Save Device” and then “Exit Application.” You will be asked to leave the program and then restart it.

10. Before restarting, first click Control-Alt-Delete, enter Task Manager, and then click on “Processes.” Find “Taskman” or “Taskmngr” and click “End Process.” Unless you do this, you will not be able to reenter the program. Instead, you will get an annoying message that says “LCTOAPC is already running.”

11. After restarting the program, click “Continue” and then the blue car in the middle of the two top buttons. Follow the instructions and click on the check mark on the bottom right.

12. Click on “Start New Session” up top and then click the check mark.

13. Click on the vehicle you are working on in the list, even though it does not look “clickable.”

14. After this, chose the toolbox on the top right and click on “programming.” Then, choose the module you want to reflash.

15. That’s it. The software will automatically tell you the vehicle’s software is up-to-date, or it will start the reflash.

This process might look easy to you, but it is not because of the several speed bumps you will run into.

What immediately comes to mind is the following:

Navigating, and having to disable pop-up blockers on the Ford Motorcraft website.

The difficulty of updating drivers for your J-Box.

Clicking tab to enter your User ID for the third time.

Restarting the Ford software with so many additional steps such as closing out “taskman” that is running in the background of your PC.

Choosing vehicles in the program from a list that does not look like you can actually choose them.

Once you get used to all of these things, reflashing is legitimately a 45-minute process on Fords. The question is, will you do enough reflashes to get used to it? I charge a customer $200 for a reflash for this reason.


Like Ford, the software for Chrysler and Fiat is relatively affordable. However, it is legitimately a 40-minute process that you need to charge accordingly for. So, how do we get started?

1. Go to and click on “TA Online-Subscriptions” up top. Simply purchase the three day subscription, add to cart, and scroll to the bottom where it says “Place Order.”

2. Have your credit card handy and fill out all the information it asks for. See the PC reset screen below? Be careful when you are hooked up to the car if that screen comes up. Be sure to let the computer reset BEFORE you hook up or you can fry a module in the middle of a reflash.

3. Go back to “Home” to the top left and click on “Tech Authority Online” to the right.

4. This is the Tech Authority Online area. This is where the reflashing gets started. Chrysler does not automatically check the car to see if its software is up to date, so you have to look through a pdf file under “Flash Matrix.”

5. After finding the correct “part number” for the updated reflash file, click on “flash.”

6. To download the actual Chrysler reflashing program you need to click “J2534 System.” Note where you download the actual software file you need for the PCM. Remember to click this later after installing the J2534 program.)

7. Downloading the J2534 program is a rather straight forward process. Just be sure your J2534 tool is not yet plugged in.

8. You will need to download Adobe Air to use the program. You can simply go to to get it.

9. Now you need to download the actual PCM file. Do the same thing as step six, but click the hyperlinked “here” under “Support for the Chrysler J2534 Flash Application.”

Input the part number, click download for the file and it will place the file somewhere you can’t see it.

Don’t worry about where it is, the program will know where to find it.

10. Connect your J2534 Device and make sure the PC recognizes your device.

11. Click on “J2534 Application” to start up the application.

12. Choose the vehicle according to what the menu asks for. Here we want to choose “Connect to 2009 or earlier vehicle” and then click “Start.”

13. Click “Select Pass Thru” and then choose your J device from the menu.

14. Now the reflashing begins as long as you follow the prompts that the program tells you.

15. You will need to periodically check your reflash. In the middle, the program prompts you to turn the key and other tasks.

That’s pretty much it. Reflashing Chryslers is an easy process once you have the kinks worked out.

Concluding remarks

Before we sum everything up, there are a few manufacturer specific silver bullets we should keep in mind:

On GMs, pre-2003 models often have problems after a reflash using a J-Box. Sometimes, you can recover what you lost by reflashing the same module with a Tech 2.

Hondas and Nissans tend to be shaky using J2534.

It is possible to use the Volvo and BMW factory scan tools by purchasing a subscription and using a J-Box. I know no one who has got them to work easily or without major problems along the way.

J2534 does not work very well on some common Ford and Chrysler diesels. Factory equipment is recommended.

Sometimes vehicles will not start or set codes without having their modules relearned/coded. This is not fun for the J-Box reflasher when he does not have the right scan tool (often factory or Autologic) to get this job done.

The J2534 standard is really just for emissions related software, so some OEMs (i.e. Chrysler) will not give you the ability to reflash modules that are not powertrain related.

These days reflashing is a necessary part of auto repair. That does not mean that you should be the one to do it or you are going to be reflashing every manufacturer that’s out there. But, you need to seriously start thinking about how you are going to approach reflashing in your shop — your customers are going to need it.

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