ECU tuning file glossary: the words on every job, explained

Tuning forums, tool manuals and file services all use slightly different words for the same things. This page collects the terms a workshop meets on a File job and says what each one means in practice — and, where FILHEX has its own word for it, which word the app uses.

The File itself

ECU File / dump / map / remap file. The binary image of a control unit's flash memory as a tool read it. It holds the calibration tables, the strategy logic and the integrity data. FILHEX calls it a File. Background: what is an ECU File?

Original / ori / org / stock. The untouched factory read of the ECU. The starting point for every modification and the only reliable way back. In FILHEX, the original File you upload.

Mod / tuned File / result. The modified File you write back. In FILHEX, the result File you download from a completed Solution Job.

.bin / .ori / .mod / tool container. File extensions and packaging. The extension is a label; what matters is that the content is a complete, unmodified read for that ECU. FILHEX scan reads the binary and tells you whether the File is supported.

Calibration / maps / tables. The regions of the File the engine management reads in real time: injection quantity and timing, rail pressure, boost or VGT targets, torque limiters, soot models, EGR and SCR strategies. A Solution changes specific maps and leaves the rest alone.

Damos / A2L / map pack / XDF. Definition files that tell a map editor where each table lives in a given ECU software. Needed only if you edit maps yourself; a file service does not need you to own them.

Hardware number / software number (HW / SW). The number of the physical ECU and the number of the firmware or calibration version inside it. File services match jobs against the pair. FILHEX reads them from the binary during scan, so you do not have to type them.

Reading and writing

OBD. Reading and writing through the vehicle's diagnostic socket. Fastest and lowest risk; some ECUs give a full read this way, others only the calibration area.

Bench. The ECU out of the car and wired on the desk through its connector. Needed for full reads of many newer or locked units and for recovery.

Boot / BSL / BDM / JTAG. Access to the processor itself with the case open. For units nothing else reaches and for repairing a failed write. BDM is the older method for early Bosch units.

Full read vs partial read. A full read is the complete flash image; a partial read is only the calibration area. Upload the complete read your tool saved; a partial read is the most common reason scan lists fewer Solutions than expected.

Virtual read (VR). An original pulled from a server by software number because the ECU is read-protected but writeable. Usable for jobs on supported ECUs — but on a car someone has already tuned, a mismatched virtual read is the classic way to brick the ECU on the write.

Flash / write / program. Writing a File back to the ECU. Use the same tool and route as the read, with a battery support unit connected.

Battery support unit (BSU). A stabiliser that holds the vehicle's voltage steady during a write. Voltage drop mid-flash is a leading cause of a bricked ECU.

Bricked ECU. A control unit that no longer starts or communicates after a failed or mismatched write. Recovery is bench or boot work; prevention is a correct original, a matching File, the same write route and a BSU.

Master / slave tool. A master tool reads open Files you can send to any file service and open in any editor. A slave tool reads encrypted Files only its paired master can open — cheaper to enter, tied to one supplier.

Clone tool. An unlicensed copy of a commercial tool. Bricked ECUs, wrong checksums, no support; many file services refuse Files that came from one.

Integrity and detection

Checksum / CRC. An integrity value the ECU computes over regions of the File. Any map change needs a recalculated checksum or the ECU rejects the File, drops into limp mode or will not start. Your write tool and the File must agree on it. The FILHEX Hex Editor warns you that it does not correct checksums on Files you edit locally.

CVN (calibration verification number) / flash counter. Values the ECU reports that let a manufacturer detect that the calibration was changed or how many times the unit was flashed. They remain even after the original is written back; a remap is detectable.

TPROT / tuning protection. A check on many Bosch units after about 2009 that verifies the File after an OBD write and refuses to start on a mismatch. Tools handle it with a bench or boot patch before OBD work.

Security gateway (SGW). A module on newer vehicles that blocks diagnostic writes until it is unlocked. Affects whether a job can be done over OBD at all.

Emissions and drivability terms

DPF / FAP / particulate filter. The filter that traps diesel soot and burns it off in regenerations. DPF Removal (DPF off, DPF delete) retires its management in the File; the filter itself must be removed or gutted. What is DPF Removal?

Regeneration / regen loop. The ECU burning soot out of the filter by raising exhaust temperature. A regen loop is a car that keeps requesting regenerations because the filter never reaches a clean state.

EGR / AGR. Exhaust gas recirculation. EGR Removal (EGR off, EGR delete) sets the valve closed in the calibration and retires its diagnostics; a blanking plate physically blocks the passage. What is EGR Removal?

SCR / AdBlue / DEF / NOx sensor. Selective catalytic reduction: urea dosed into the exhaust to cut NOx, measured by NOx sensors. AdBlue / SCR Removal retires the dosing strategy, sensor feedback and the countdown that ends in a no-start.

GPF / OPF. The petrol equivalent of a DPF.

Swirl flaps / tumble flaps / TVA. Intake-manifold flaps and the throttle valve actuator on diesels. Fail mechanically, raise plausibility codes, and are often removed with a matching Solution.

DTC / fault code / MIL / EML. Diagnostic trouble codes and the warning lamp. DTC clear switches selected codes off in the File so they do not return — for hardware no longer fitted, not for live faults. In FILHEX it is free on the result File, up to 3 times.

Limp mode / reduced power. The ECU's protective state after a fault it treats as serious. A File that does not match the hardware state is a common cause after emissions work.

Readiness monitors. The self-test flags an inspection reads. A Readiness Calibration keeps them consistent after systems have been removed.

Performance terms

Stage 1. Software-only performance calibration for a healthy car on stock hardware. Stage 1 File workflow

Stage 2. Calibration that expects supporting hardware — intake, downpipe or exhaust, often an intercooler. Stage 2 is not a bigger Stage 1

Stage 3. Turbo and fuelling upgrades with a bespoke calibration. Outside the scope of a catalog File.

Eco map / economy remap. A calibration aimed at torque in the normal driving range and lower consumption rather than peak power.

Vmax / speed limiter / soft limiter. Caps the ECU enforces on road speed or engine speed. Removed with the matching Solutions where published.

Pop & bang / burbles / hardcut. Exhaust noise and rev-limiter behaviour changes on petrol engines. Popbang / Burbles Activation in the FILHEX catalog.

TCU / DSG / gearbox file. The transmission control unit and its calibration. TCU Solutions adjust shift behaviour and torque limits after engine work.

FILHEX words

Solution. One modification you select on a File: DPF Removal, Stage 1, DTC clear.

Solution Job. One original File plus the selected Solutions, producing one result File.

Credit. The unit you pay with: 1 Credit = 1 processed File, whatever Solutions are on it. Scan, DTC clear and the Hex Editor never spend Credits. Pricing

Workspace. Your workshop's account: one wallet, one job history, one place every File lives.

Scan. The free step that reads the uploaded binary, identifies Brand and ECU, and lists the Solutions that apply to that software version. How File scan confirms Solutions

Hex Editor. The comparison tool in the FILHEX app: original and result side by side, every difference listed, values as numbers or a graph. For checking a File, not for authoring maps.

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