Feature
Fast Parameters — edit FCA / Stellantis configuration by name
Most market and retrofit jobs come down to a handful of settings. Fast Parameters let you change them by parameter name — country/region, language, lighting, units, retrofit flags — instead of hunting for the right raw byte. You see the current value, set the new one, and the tool keeps the file checksum-correct.
Edit by name, not by raw bytes
Standard mode lists configuration options as named parameters with their current and new value, so you change exactly what you intend — and nothing else. No converting a setting into a byte offset and a bit mask in your head, and no guessing which nibble controls which option.
What you can change
- Country / region code — market behavior and regional menus where supported.
- Interface language — cluster and infotainment language options.
- Lighting behavior flags — DRL logic and lamp-behavior options the BCM and equipment already support.
- Units — km/h vs mph, temperature and pressure units where the platform allows.
- Retrofit enable/disable flags — turn supported module features on or off (camera, ACC/ADAS menus, audio types, etc.).
Rule of thumb: configuration can enable features the hardware and firmware already support.
Where the names come from
Fast Parameters are backed by a factory parameter database, so options show up under names you recognize rather than as anonymous offsets. The PROXI Map Editor presents a named parameter table with current and new values, which makes review and double-checking before a write much faster.
Standard vs Advanced — you keep both
Standard gives you Fast Parameters by name for everyday market/retrofit work. Advanced still exposes the raw byte grid with bit-level editing (Bit Magic) for the cases where you need to touch a specific bit directly. Same file, two levels of control. See the PROXI alignment workflow.
Checksum-correct after every change
Editing without recalculating the checksum is where most “mystery” results come from. After you change parameters, FCA PROXI Tool recalculates CRC for the configuration buffer so the exported file stays internally valid and the vehicle accepts it predictably. You can work with exported buffers or connect directly over ELM327 / J2534 on supported platforms.
How Fast Parameters fit the workflow
Read the configuration (Direct Connect or your diagnostic workflow), edit the named parameters you need, save CRC-correct output, then write and verify on the vehicle. If a write is rejected, the diagnostics module decodes the EOL rejection reason by parameter name so you know which setting to adjust.
FAQ
What are Fast Parameters?
They let you edit FCA/Stellantis configuration by human-readable parameter name — drawn from a factory parameter database — instead of hunting for the right raw byte or bit. You pick the setting by name and change its value.
How is this different from raw byte editing?
Standard mode exposes named parameters (with current and new value), so you change exactly the intended option. Advanced mode still gives you the raw byte grid with bit-level editing when you need it. Most market and retrofit tasks are faster and safer by name.
What can I change with Fast Parameters?
Typical items include country/region code, interface language, lighting-behavior flags, units (km/h vs mph), and retrofit enable/disable flags — wherever the platform and equipment support them.
Does the output stay checksum-correct?
Yes. After you change parameters the tool recalculates CRC for the configuration buffer, so the exported file stays internally valid and the vehicle accepts it predictably.