PROXI alignment / PROXI configuration
PROXI alignment workflow, explained for workshops
A practical overview of PROXI alignment-related work: what it is, when it appears, and how FCA PROXI Tool helps you edit the configuration map (bytes/bits) and generate a consistent output file with recalculated CRC. Note: many people search this as “proxy alignment”, but the correct FCA term is PROXI.
Concept
What PROXI alignment is
PROXI alignment is a configuration synchronization procedure used on many FCA/Stellantis platforms. It ensures that modules share the same configuration map. You typically encounter it after retrofits, module replacement, or configuration mismatches.
Tool role
What the tool does (and why PROXI alignment is often not needed)
FCA PROXI Tool edits configuration buffers (bytes/bits) and produces a checksum-correct output. Direct Connect can also read & write supported configuration buffers directly via ELM327-compatible adapters or J2534 PassThru (drivers may be required).
Important: you do not have to write the changed file to every ECU or run a full network alignment every time. In typical retrofit/conversion workflows you can write only to the specific ECU(s) that need the change. FCA PROXI Tool keeps the original Configuration Code (the identity used for ECU synchronization) while recalculating the required CRC/checksums with our proprietary logic so the vehicle accepts the file. Because the Configuration Code stays the same, the vehicle usually does not enter a PROXI mismatch state (no blinking odometer just from the edit), so a separate PROXI alignment routine is often unnecessary.
Workflow
Typical workshop workflow
- Read configuration buffer (Direct Connect or your diagnostic workflow).
- Open the buffer in FCA PROXI Tool (Standard / Advanced / PROXI Map Editor).
- Edit bytes/bits (including bit-level editing when needed).
- Save output with CRC recalculated to keep the file consistent.
- Write back and validate on the vehicle (Direct Connect or your diagnostic workflow).
Model-specific guides (new platforms)
If you work mostly on the newest platforms, start here. These pages focus on the practical symptoms, access realities, and workflows for each model.
Jeep
Jeep Grand Cherokee WL
PROXI (proxy) alignment symptoms and a configuration-first workflow for WL / WL74 platforms.
Ram
Ram DT 2025+
What to expect on DT 2025+ after changes: SGW access notes, “alignment failed” troubleshooting, and workflow.
Jeep
Jeep Wagoneer / Grand Wagoneer
PROXI (proxy) alignment symptoms and a configuration-first workflow for Wagoneer family vehicles, including SGW/access notes.
Alfa Romeo
Alfa Romeo Tonale
PROXI (proxy) alignment guide focused on configuration mismatch triggers, failure modes, and a clean write-back workflow (Tonale / Hornet overlap noted). Includes SGW access notes.
Dodge
Dodge Hornet
PROXI (proxy) alignment / configuration mismatch guide for Hornet, with a configuration-first workflow (keep Configuration Code, checksum-correct output, write only to selected ECUs). Includes SGW access notes.
Jeep
Jeep Wagoneer S
PROXI (proxy) alignment / configuration mismatch guide for Wagoneer S: access notes and a configuration-first workflow with checksum-correct output.
Maserati
Maserati Grecale
Configuration mismatch and “proxy/proxi alignment” topics for Grecale, with access realities and a targeted write-back workflow.
Conversion solutions (files & instructions)
Working on a retrofit or market conversion? If your project includes radio / infotainment USA→EU changes, check the conversion solutions page.
Head unit USA→EU conversion
VP4R Panasonic • VP3/VP4 Harman • Maserati Touch Connect • Uconnect 5 (R1)
PROXI alignment, in plain workshop terms
People use “PROXI alignment” to describe two related things: the vehicle configuration data (often called PROXI configuration)
and the alignment procedure that synchronizes that configuration across modules. Mixing those two is where most confusion starts.
Short version: the alignment routine copies the current vehicle configuration from the BCM to other modules.
You usually run it after a retrofit, module replacement, or whenever the car reports a configuration mismatch (for example, a flashing odometer on many FCA platforms).
7) FAQ
Short answers to common real-world questions.
8) References
External sources used for factual claims on this page.
What PROXI alignment is (and what it is not)
On many FCA/Stellantis vehicles the Body Control Module (BCM) holds a “feature map” style configuration.
The alignment procedure is the part that propagates that configuration to other modules, so they agree on what equipment is present and how it should behave.
Definition
Alignment = synchronization
The alignment routine copies the current vehicle configuration from the BCM to other modules on the network.
That is why it’s commonly used after changes: when modules disagree, the car complains until the configuration is consistent again.
BCM as “source of truth”
Copies config to other ECUs
Solves mismatches
Clarification
Editing ≠ alignment
Editing is changing bytes/bits in the configuration buffer (for example: retrofit flags, regional settings, module presence).
Alignment is the diagnostic procedure you run when the workflow calls for it, to push the configuration across modules.
A configuration editor helps you prepare a clean, consistent file; the alignment is still executed by a diagnostic tool.
Edit: bytes/bits
Align: diagnostic routine
Different steps
Reality check
Not every car uses PROXI
“PROXI alignment” is an FCA term used on many (not all) platforms and model-years.
The exact routine name, menu location, and required network adapters can differ between vehicles and diagnostic software versions.
Platform-dependent
Tool-dependent
Model-year dependent
Where you see it in official tooling: in wiTECH documentation and TSB workflows the Proxi Alignment / Proxi Configuration Alignment routine is referenced under the BCM and may appear in areas like “Miscellaneous Functions” or “Vehicle Preparations”, depending on context and software version.
When PROXI alignment is typically required
The alignment routine is commonly used after you change equipment or module presence. Think of it as “the car learning the new lineup”.
If you edit configuration but never synchronize it where required, the system can keep reporting mismatch symptoms.
After hardware change
Retrofits and module replacement
Typical triggers include retrofits (radio, cluster features, cameras), replacing a module, restoring a BCM configuration, or resolving a communication/config mismatch after repairs.
Many professional diagnostic workflows explicitly call for Proxi Alignment after certain procedures.
After config change
Configuration mismatch conditions
If the BCM configuration does not match what other modules report (or a “new” module is detected), some vehicles indicate a mismatch until alignment is completed.
This is one reason workshops keep a repeatable “read → edit → write → align” playbook.
Cost control
Avoiding trial-and-error
A clean configuration file with consistent checksums reduces guesswork.
You want each change to be intentional, traceable, and reversible, especially when you’re doing multiple retrofits in the same session.
Common symptoms of a PROXI / configuration mismatch
Symptoms depend on model and platform, but there are patterns that keep repeating in real workshops.
Always confirm with diagnostics, because a warning light can have multiple causes.
Dash indicator
Flashing odometer (on many FCA platforms)
A flashing odometer is widely documented as a sign of configuration mismatch or an unrecognized/unaligned module.
It is often seen after head unit swaps or aftermarket installs when the network “sees” something different than what the BCM configuration expects.
Diagnostics
Module configuration status not “aligned”
Some diagnostic tools show a per-module status table for PROXI configuration (configured / not configured / not applicable).
If one or more modules report mismatch, alignment is part of the standard repair path.
Network side effects
Feature missing or wrong behavior
If the configuration says a feature is present but a module does not accept it (or vice versa),
you can see missing menu items, disabled options, or warnings after a retrofit until the configuration is consistent again.
Important: PROXI alignment is not a magic “clear all” button. If a module is genuinely faulty, has communication issues, or the vehicle has an unrelated DTC,
alignment may complete but the problem may remain. Use it as part of diagnosis, not as a substitute for diagnosis.
A practical PROXI alignment workflow
This is the workshop-friendly sequence most techs follow when configuration changes are involved.
It keeps your changes controlled and reduces the “why did that checkbox break something else” moments.
Why PROXI alignment can be unnecessary after a file-based change: on many FCA/Stellantis platforms, the synchronization check is based on a configuration identity (often described in workshops as a configuration identity (often called PROXI code)), while the actual feature behavior lives in configuration data protected by CRC. If you modify configuration data and recalculate CRC correctly without changing the original configuration identity, modules continue to agree on the configuration identity after flashing. In that case, no mismatch state is triggered and PROXI alignment is typically not required.
Step 1
Read and archive the original configuration
Start by reading the configuration buffer with Direct Connect (ELM327/J2534) or your diagnostic workflow.
Save a clean backup before changing anything. That backup is your “undo” button.
Step 2
Edit the configuration intentionally
Change only what you need (module presence, retrofit flags, regional features).
When you can, prefer bit-level edits with clear visibility into what changes inside the byte.
FCA PROXI Tool is designed around this exact step: Standard view for speed, Advanced view for precise control, and a map-driven editor when you want structure.
Step 3
Keep the file consistent (checksum/CRC)
In many FCA diagnostic workflows, the configuration buffer is protected by a checksum (often CRC).
If you modify bytes but do not regenerate the checksum correctly, you can end up with invalid output that is rejected by tooling or behaves unpredictably.
A dedicated editor that recalculates checksums automatically saves time and prevents avoidable failures.
Step 4
Write back to needed ECUs and validate
Write the updated configuration using your established diagnostic method and confirm the change took effect.
Clear and re-check DTCs where appropriate, and verify the target features on the vehicle.
Checksum/CRC: why configuration editing needs discipline
In workshop practice, the easiest way to waste time is to edit configuration bytes and ignore file integrity rules.
Configuration buffers are commonly checksum-protected (often CRC). When you change bytes, the checksum must match the new content.
Problem
“I changed one flag and now everything is weird”
The root cause is often not the flag itself, but the file integrity after editing.
Incorrect checksum handling can lead to invalid output files or changes that don’t behave as expected.
Solution
Use an editor that makes integrity automatic
FCA PROXI Tool recalculates CRC for supported buffers and marks modified bytes so you can see what changed.
That’s not “fancy UI”. It’s the boring part you want 100% correct every time.
Good practice
Keep change sets small and reversible
Do one logical change set, save, validate, and only then move on.
When troubleshooting, smaller diffs are faster to reason about than “I toggled 30 things and hoped”.
Changelog
This page is an educational guide about PROXI alignment. Product release notes are published separately and also shown inside the app (built‑in update checker).
Where to read it: changelog.json (machine‑readable) and the in‑app changelog screen.
If you’re evaluating the tool for workshop use, the changelog is the best place to see what changed between versions.
Need a clean way to edit PROXI configuration?
FCA PROXI Tool is built for the “read → edit → checksum → output” part of the workflow.
It keeps the work transparent: you see the bytes, you control the bits, and the output stays consistent.
Independent third‑party software. Not affiliated with FCA/Stellantis.
FAQ
Short, no-drama answers to questions that come up in real jobs.
Does PROXI alignment “program” a module?
It synchronizes configuration (feature map) across modules. It does not replace ECU flashing or firmware programming.
If a module needs software updates, that’s a different procedure.
Why is the BCM mentioned so often?
Many descriptions of PROXI alignment treat the BCM as the module that holds the current vehicle configuration and distributes it to other ECUs during the routine.
My odometer is flashing. Is it always PROXI?
It’s a common indicator of configuration mismatch on many FCA platforms, but it’s not the only possible cause of problems.
Confirm with a diagnostic scan and the tool’s configuration status view if available.
Can I edit the configuration and not run PROXI alignment?
Often, yes, in file-based workflows. If configuration data is modified while the original configuration identity used for ECU synchronization is preserved, and the CRC is recalculated correctly, modules continue to agree on the configuration identity after flashing. In that scenario, the vehicle does not enter a PROXI mismatch state, so a PROXI alignment procedure is typically not required.
If the configuration identity changes, a module reports a mismatch, or the diagnostic workflow explicitly requires it, then PROXI alignment is needed.
Where does FCA PROXI Tool fit in?
It’s a configuration editor: you load a buffer, change bytes/bits in a controlled way, and save an output with checksum handling.
The alignment routine is executed by diagnostic software.
References (public sources)
This page avoids “forum mythology” where possible. The sources below are used for the core factual statements
(what the routine does, typical triggers, and where it appears in wiTECH workflows).
Definition
Snap‑on Technical Focus: “What Is Proxi Alignment?”
What it does + symptom
Appcar DiagFCA: Proxi Configuration Alignment
OEM workflow (example)
NHTSA TSB PDFs referencing wiTECH Proxi Alignment
Tool coverage
MultiECUScan + AlfaOBD official pages
