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David Holdeman edited this page Jan 7, 2023 · 6 revisions

Hellen 121 VAG

Hellen Plug&Play for ME7 VAG vehicles

Download release firmware Snapshot firmware bundle

Pinout EBAY

Schematics rev a

Schematics rev b iBom rev b

KiCAD source files

Status: early phases of testing!

Hardware features

  • Electronic Throttle Body
  • knock detection module with headphone jack
  • build-in WBO - WARNING 4.2 software not ready while we believe that hardware is universal (footprint, stm32f042 not in stock at JLC)
  • Baro sensor LPS25HB (footprint, not populated)

Vehicle Specific Jumpers

Main Relay option Never have both R2 and R3 jumpers populated!

Voltage Input option Never have both R8 and R9 jumpers populated!

Raw +12 option Never have both F1 and F2 jumpers populated!

Vehicle R2 R3 R8 R9 F1 F2
2000 Early Audi A4 1.8T (ME7.1, NBO2, NO VVT, DBW)
2001 Audi A4 1.8T (ME7.5, WBO2, VVT, DBW)
2002 Audi Allroad 2.7t apb
2006 Jetta 2.5 BGQ
2003 Audi A6 3.0 ? ?
2003 Audi A6 4.2
2001 VR6 12V AFP
2002 VR6 24V BDF
2004 Cayenne 3.2
Other model ? ? ? ? ? ?


Connector Pinout Spreadsheet, with links to wiring drawings







Q: what cars is the 121vag applicable for?

A: We do not know the whole list. Definitely B5 1.8T Passat but could also work on 5 cylinder Jetta and VR6 and even a 8 cylinder A8. Whatever VAG product with a 121 header please check Hellen pinout above and let us know :)

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