Guided diagnostics for classic W124 owners.
W124 Diagnostic Assistant helps Mercedes-Benz W124 owners locate the diagnostic socket, connect a simple blink-code reader correctly, count LED flashes, and understand OBD1 fault-code results with clear safety guidance.
W124 Diagnostic Assistant
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GET IT ONGoogle PlayEverything needed for manual W124 OBD1 diagnosis
Built for real garage use: clear text, guided steps, socket awareness, and no assumption that the user already knows old Mercedes diagnostic procedures.
Diagnostic Socket Locator
Explains where the W124 diagnostic connector is typically located and prepares users before any connection is made.
16-Pin X11/4 Guide
Visual guidance for the 16-pin diagnostic socket used by the current M111/M104 HFM-SFI workflow.
Banana Plug Connection Help
Shows how ground, power, and signal/test leads are connected when using a simple homemade blink-code reader.
Blink Counter
Large garage-friendly controls help the user count LED flashes and submit the blink code safely.
Fault-Code Results
Displays fault title, description, possible causes, first checks, severity, confidence label, and source notes where available.
Diagnostic History
Lets users save diagnostic readings with notes, helping them track recurring or intermittent faults over time.
Safety Warnings
Built-in reminders help prevent random pin probing, shorts, and unsafe work around sensitive systems such as SRS.
AI-Assisted Drafts
Optional AI assistance can prepare unverified draft explanations for missing data, but verified diagnostic records are not modified automatically.
Offline-First Database
Core supported diagnostic data is stored locally so the app remains useful without relying on constant network access.
Support scope and roadmap
The app is honest about what is supported now and what requires different diagnostic workflows later.
1993–1995 W124 M111 / M104 HFM-SFI
Current active support focuses on M111 and M104 engines using the 16-pin X11/4 diagnostic socket and manual blink-code reading.
M119 V8
Advanced OBD1 / multi-module support is planned for V8 models such as E420 and E500.
M102 / M103
KE-Jetronic / CIS-E engines require duty-cycle or analog diagnostic workflows, not the same HFM blink-code flow.
OM601 / OM602 / OM603 / OM604 / OM606
Diesel diagnostic support is planned as verified information and safe procedures are added.
More systems
Future expansion may include SRS, climate control, cruise/idle, ABS/ASR, transmission, and additional verified modules.
Diagnostic groups explained
Different W124 engines do not all use the same diagnostic method.