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HomeFile toolsCaterpillar .FLS file identification
Caterpillar · ADEM 2000 / III / A4 · 3126 · C-7

Caterpillar .FLS file identification online

Reads the part number, rating and memory layout out of a Caterpillar .FLS, and says whether it is still intact. Runs in your browser against our server — there is nothing to install and no licence to keep alive.

Also called:identify Caterpillar FLS filewhat is this CAT flash fileCAT part number from flash fileread FLS fileCaterpillar rating from fileis my FLS file stockADEM flash file readerOLS289 file info
Processed in memory · no copy kept
50 credits
$50.00 per file · charged only when it works
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Cost if we can do it: 50 credits

Sending costs nothing. We confirm we have your file, run the job on our server and tell you whether we can do it. You decide about paying after that — and you get a ready-to-use .txt file.

How it works

Four steps, and you find out whether it can be done before you pay anything. What you get back is a ready-to-use .txt file.

1
Send your file

Upload it here. We confirm on screen that it arrived, with its name and size. This costs nothing.

2
We check it and tell you

We run the whole job on our server and answer one question: can we do this file, yes or no. If the answer is no you are told why, and nothing is charged — ever.

3
You accept the terms and pay

Only if the answer was yes. The price is shown before you decide, you tick to accept the payment terms, and the credits come off your balance.

4
Download your file

Straight away, in the browser. Your file is processed in memory and never written to our disks.

How you pay

This tool costs 50 credits per file. Credits are prepaid and one credit is one US dollar50 credits is $50.00, with no subscription, no monthly fee and no minimum order.

You buy credits with a card or a PayPal account on the credits page, in packs — the larger packs carry a bonus, so a shop doing several files a week pays less per file. Credits do not expire and every movement, spent or returned, is listed in your account. Before any payment goes through — buying credits, or spending them here — you tick a box to accept the payment terms, and they are shown in full at that moment rather than hidden behind a link.

If a job fails after you have paid, the credits go back to your balance automatically and a refund line appears in your history. You are never charged for a file you did not receive.

How the Caterpillar .FLS file identification works

Caterpillar flash files arrive named 2707127.FLS, or 2707127Tuned.7cz.fls, or something a previous owner renamed years ago. This opens one and tells you what is actually in it: the Caterpillar part number, the group code, the software date code, the interlock code, and the rating lines the file prints for itself — horsepower at rpm and peak torque at rpm, exactly as Caterpillar wrote them.

It also maps the memory. How many modules the file programs, which bank each one goes to, how many records and fill runs each block holds, how many bytes of ECU memory it covers and which address range. That is the difference between a full program file, a small patch module and a primer, and it is not something you can see from the size on disk.

Then it checks the file over. Every record in a .FLS carries its own check byte, so a file that has been through somebody else's hex editor usually announces itself: the report lists the exact line numbers that no longer add up. It also compares the module against a reference list of stock calibrations and, when it recognises the base, says plainly whether the file is still the untouched original or has been edited since.

Everything is read out of the file itself, so a renamed file still reports the right part number.

What we have actually tested. Verified against a 35-file Caterpillar library — 3126, C-7, C-10, C-12, C-13, C-15 ACERT, marine and primer files, encrypted and plain, 108 KB to 2.3 MB. Every one was parsed completely, with the part number, layout and record checksums read from all of them. One file in the library turned out to be corrupted on disk, and the report named the line.

Questions

Can it tell me whether the file has been tuned?

When the base calibration is one we hold a reference for, yes — it says whether the module still carries the checksum its original had. When it is a base we have never seen, it says that instead of guessing. Broken record checksums are reported either way, and those are a strong sign a hex editor has been through the file.

Does it show me the maps?

No. Most Caterpillar builds are encrypted and the maps need the WinOLS OLS289 plug-in to read. What this gives you is the identity and the structure of the file, which is what you need to know before you spend an editor licence on it.

The file has been renamed. Does that matter?

No. The part number, ratings and date codes are stored inside the file, so the name is irrelevant.

Do you keep a copy of my file?

No. The file is processed in memory and never written to disk. Nothing is stored, nothing is indexed, and the result only exists in your browser once it comes back. Close the tab and it is gone.

What happens if it fails?

The credits go back to your balance automatically and a refund line appears in your credit history. You are only ever charged for a file you actually received.

Do I need to install anything?

No. It runs on our server, so it works from a workshop laptop, a machine in the yard, or a computer that has never had manufacturer software on it. There is no licence, no dongle and nothing to keep alive.

This tool
Price50 credits ($50.00)
You upload.fls
You get back.txt
Max size16 MB
Applies toADEM 2000 / III / A4 · 3126 · C-7 · C-10 / C-12 · C-13 · C-15 ACERT · OLS289
What you get
  • A ready-to-use .txt file, in seconds
  • A yes-or-no answer on your file before you pay anything
  • Works from any machine — nothing to install or license
  • Charged per file, only when it succeeds
  • No copy of your file is kept, ever