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Wiring Diagrams

Curated free sources for ECU pinouts, schematics & circuits

Section
Wiring Diagrams
Free websites
AutoZone Repair Guides
Free
Free wiring diagrams for most US/UK models
FreeAutoMechanic
Free
Wiring diagrams + free repair manuals
ProCarManuals
Free
Free PDF wiring diagrams by make/model
BBB Industries Wiring
Free
Alternator/starter wiring references
Mitchell1 DIY
Free trial
1 free vehicle on signup, then paid
Forums with member-shared diagrams
BimmerForums (BMW)
Free
User-uploaded ECU wiring + DIY threads
VW Vortex
Free
VW/Audi wiring & ECU pinout threads
FordForums.com
Free
Ford wiring schematics shared by owners
MHH Auto
Free
Free wiring diagram requests, large library
Coming soon — built-in diagrams
🛠️ Native UK wiring library
Premium
We're building a searchable wiring diagram library in-app. Free for popular UK models, premium for full library.

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