PACCAR MX-13 (Delphi) checksum fix online
Rebuilds the block checksums of a PACCAR MX-13 Delphi read. Upload your file and it comes back ready to use, corrected automatically — the calibration content is never touched, only the integrity value.
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 the same file with a correct checksum.
How it works
Four steps, and you find out whether it can be done before you pay anything. What you get back is the same file with a correct checksum.
Upload it here. We confirm on screen that it arrived, with its name and size. This costs nothing.
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.
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.
Straight away, in the browser. Your file is processed in memory and never written to our disks.
How you pay
This tool costs 120 credits per file. Credits are prepaid and one credit is one US dollar — 120 credits is $120.00, 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 PACCAR MX-13 (Delphi) checksum correction works
This is the family WinOLS handles with the plug-in numbered OLS810: the Delphi ECU fitted to the PACCAR MX-13, which is what sits under a Kenworth T680 or a Peterbilt 579. Reads come off it at 764 KB, 768 KB or 1020 KB, and the full image WinOLS shows you is 3 MB.
The scheme is the simplest of any tool on this site, and unusual: it is an exclusive-or, not a sum. Every 32-bit word of a block is xored together and the four bytes at the very end of the block hold whatever makes the total land on one fixed constant. Edit a map and the total moves by exactly the amount you changed.
Because it is xor rather than addition, the stored value splits into two halves that never talk to each other — a change at an even word-offset only ever moves the first two bytes, an odd one only the last two. That is worth knowing if you have ever looked at a before-and-after pair and wondered why only half the value moved.
A read can carry a second, four-kilobyte identification block on the end holding an ASCII part number; it is checked and repaired by the same rule. The full 3 MB image is handled too — there the calibration sits at its real flash address with everything before it erased, and the tool finds it rather than assuming a size.
Questions
The MX-11 shares this ECU family, but we have only verified the MX-13 and we will not claim more than we have tested. Upload an MX-11 file anyway — the format check is free and it will tell you plainly whether this tool recognises it.
Either. A plain read and a full image are both handled, and the corrected file comes back in the same shape and size you sent.
No. Reads taken off an MX-13 often have no extension at all. Upload it as it is — the check reads the contents, not the name.
No. Only the bytes that hold the checksum are rewritten. Every map, limiter and parameter is returned exactly as you sent it — the file comes back the same size, and if you send a file whose checksum is already correct you get back a file identical to the original, byte for byte.
No. The file is processed in memory and never written to disk. Nothing is stored, nothing is indexed, and the corrected file only exists in your browser once it comes back. Close the tab and it is gone.
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.
No. It runs on our server, so it works from a workshop laptop, a phone in the yard, or a machine that has never had tuning software on it. There is no licence, no dongle and nothing to keep alive.
| Price | 120 credits ($120.00) |
| Accepted | .bin · .ori · .mod |
| Max size | 16 MB |
| ECU families | MX-13 EPA10 · MX-13 EPA13 · MX-13 EPA17 · Delphi · OLS810 |
- The same file back with a correct checksum — content untouched
- 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
| Cummins calibration | 100 cr |
| Calterm configuration | 100 cr |
| Detroit / Mercedes ACM & MCM | 100 cr |
| Siemens SID OLS280 | 100 cr |
| Bosch EDC17 / MED17 | 100 cr |