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map location techniques

VAG (Audi/VW/Seat/Skoda) — CROSS-PLATFORM map-location & tuning methodology. Covers Bosch Motronic petrol (ME7.x, MED9.1, MED17.x), Continental/Siemens Simos (Simos18), and Bosch diesel EDC (EDC15/EDC16/EDC17). Written as a "how to find and validate maps in a stock file when no definition exists" playbook that applies across those families, with per-platform specifics called out. Identify the PLAT

Reference - updated 4 August 2026

The ECU hardware

Petrol Motronic: ME7.1/ME7.1.1/ME7.5 = 16-bit C166-core MCU (Infineon/Siemens C167CR/CS or, on later boxes, ST10F275) with EXTERNAL AMD/Spansion 29Fxxx NOR flash. Image size is per-box — VERIFY from the dump, do not assume: 1.8T ME7.5 is typically 512KB (29F400-class); the 2.7T ME7.1 8D0907551 is C167CR-based and has been read as both 512KB and a full 1MB (29F800) dump depending on rev/read method; 4.2 V8 ME7.1.1 = 1MB. MED9.1 = Infineon TriCore TC1766. MED17.1 = TC1766/TC1767; MED17.5 = TC1791/TC1797-class. Simos18 (Continental/Siemens) = TriCore TC1791. Diesel: EDC15 = C167 (16-bit); EDC16 = TC1766; EDC17 = TC1767/TC1791/TC1793. Newest EA888 evo/EA839 petrol move to Bosch MG1 and diesel to MD1 (TC3xx Aurix) with secure boot — out of scope for OBD tuning, bench/BSL only. Rule of thumb: C166/ST10 = older 16-bit segmented (DPP-paged) architecture with external NOR; everything TC17xx = 32-bit TriCore with on-die PMU program flash + DFlash.

Fuelling and load sensing

Both — petrol (Motronic ME/MED) and diesel (EDC common-rail and older PD)

How this ECU is read and flashed

ME7 (C167/ST10): OBD over K-line KWP2000/ISO14230 — header type is PER-ECU (some answer no-address, some physical, so PROBE both). Read via ReadMemoryByAddress (23); WRITE via session 10 85 (immo-gated on some, e.g. 4Z), SecurityAccess 27, RequestDownload 34, TransferData 36 37. Immo boundary is real: dev session (10 86 14) + read (23) reaches EEPROM/RAM immo-free but NOT flash — flash is immo-gated (needs 10 85 / matched car / SKC), so use BENCH BOOT MODE (C167/ST10 BSL over K-line, immo-immune) which requires grounding ONE internal boot pin (e.g. flash pin24->P0L.4; can't be done cable-only). MED9.1 (TC1766): CAN TP2.0/UDS — flash READ must NOT enter session 0x86 (reboots to BSL, needs a power-pull); 0x27 alone enables reads; cal-write arms via 33C4->73 with a 31C5 re-arm before each 33C5 poll; full recovery = bench BDM/BSL; immo via M95160 EEPROM on CH341A. EDC16 (TC1766)/MED17/EDC17 (TC1767/1791/1793): OBD UDS with SecurityAccess seed/key + boot-mode bootloader upload, or BENCH BOOT via TC1791_CAN_BSL (boot pins/BDM). Simos18 & later signed MED17.x/EDC17: OBD flash of the ASW needs the SBOOT seed/key path (bri3d/Simos18_SBOOT); a CAL-only tune on Simos18.1 just needs a valid CRC32 (CAL unsigned), while Simos18.10/newer signed CAL needs SBOOT/bench; the OBD transfer uses AES-128 'Encryption A' + LZSS 'Compression A'. General: bench/boot tools (KESS/KTAG/CMD/Autotuner/bFlash and open-source TC1791_CAN_BSL) bypass immo & signature gates that OBD can't. Newest MG1/MD1 (TC3xx) add secure boot/ECDSA — treat as bench-only. Always correct/replace checksums (and re-sign or route around a signature where present) before writing.

Engine codes in this family

Staging - what each stage really gives

Safety limits

How confident is this?

SOLID: ME7 map roles, torque-monitor math, and the checksum toolchain (grounded in S4wiki, NefMoto, ME7Sum/ME7Check/ME7Logger, and live K-line/bench work); the LOCATION methodology (identity-string->def, axis-signature scan with an EXACT-close requirement, stock-vs-tune diff, interpolation-kernel pointer tracing, decode-to-sane validation with the uniform-map/zero-cell dtype+endianness gate); Simos18/TriCore flash architecture, CRC vs signature layering, and access paths (grounded in bri3d/VW_Flash, Simos18_SBOOT, TC1791_CAN_BSL); WinOLS/DAMOS/A2L as the pro definition standard. CORRECTED IN THIS PASS: RSA/signature enforcement is NOT universal — it is Simos18.x, later MQB EDC17/Simos12, and MG1/MD1; ordinary MED9.1/MED17.1/17.5/EDC16/early-EDC17 are multi-region CRC only (no signature). The 3.0T supercharged is MED17.1, NOT MED9.1. ME7 image size (512KB vs 1MB) varies per box — verify from the dump, don't assume a chip. THIN / MUST-VALIDATE (do NOT treat as fixed): exact per-file FLASH ADDRESSES for any map (come only from a matching def or from signature+diff+validate on the specific box, never invented); precise checksum ranges/polynomials and the exact set of signed blocks vary

VAGPULSE reads, backs up, tunes and flashes these ECUs over OBD from a Windows laptop - diagnostics, fault codes, coding and Stage 1-3 maps in one app, with your original file saved first and checksums corrected automatically.

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