ECU checksum correction is an optional add-on service that recalculates and updates the integrity values inside the ECU file after tuning. It ensures the modified file is accepted by the ECU without errors or unexpected limp-mode.
ECU Checksum Correction Service
A checksum is a mathematical integrity value stored inside the ECU firmware. Whenever you modify maps (fuel, torque, boost, DTC, DPF/EGR/AdBlue off, etc.), the checksum must be recalculated and updated. If not, the ECU may reject the write, enter limp mode or simply not start after flashing.
Important: checksum correction is a separate, optional service. If your flasher does not reliably fix checksums, or you prefer a pre-verified file, add the
Checksum Correction add-on at checkout and receive a validated file ready to flash.
Low-quality clone devices often apply incomplete or wrong checksum logic (wrong regions, polynomial/endianness, or missing EEPROM), which can cause failed writes or even a bricked ECU.
Supported ECU Families – Detailed Coverage
About ECU checksum (quick technical notes)
- When it’s required: after map changes, cloning/immo off, OS or segment swaps, EEPROM edits.
- Common issues with bad checksum: write aborted, no-start, fan always on, MIL on, limp mode.
- Where it applies: main flash and often EEPROM (Bosch MED/EDC17, MD1/MG1; Marelli IAW/MJD; Delphi DCM/MT; Siemens/Continental SID/SIMOS/EMS; Denso/Transtron; TRW).
Best practice: always validate checksums before flashing. If you are unsure, add the
Checksum Correction add-on and we will return a pre-verified file ready to write.
Other ECUs currently covered by our checksum service
This legacy list shows additional ECUs supported by our checksum engine. All of them can be handled as an optional service when you purchase a tuning file.
- Bosch EDC PLCC
- Bosch EDC15 29F400
- Bosch Alfa CR
- Bosch BMW CR
- Bosch PSA HDi
- Bosch VW 115cv
- Siemens BMW MS41/MS42
- Bosch Smart E2/E3/E4
- Bosch Fiat E3 JTD
- Bosch Merc 1MEG
- Bosch Mer Gasoline
- Volvo V70 F400/F800
- Siemens F200/F400
- Bosch VAG ME7 F400/F800
- Bosch EDC15 29F400 V2
- Bosch ME 3.2 / 7.3
- Bosch Nissan TDDI
- Siemens HDI
- Siemens Renault 29F200/29F400
- Siemens Volvo T4
- Siemens MS43
- Siemens Rover
- Bosch ME7 Alfa/Hyundai
- Cherokee CDI
- Siemens Ford SIM
- Ford TDCi
- Bosch BMS46
- Bosch Peugeot ME7
- Bosch Volvo CR2 (2003)
- Bosch Smart CDI E3
- Bosch BMW ME7
- Bosch Porsche ME7.8
- Siemens Ford TDCi (2004)
- IAW 4AF/59F/5AF
- Marelli 5NF E4
- Delphi Ford TDCi
- Ford EECV / EECVI
- Siemens Truck F400
- Marelli MJD
- Marelli 6LP
- Siemens BMW MSS5x
- Siemens Mini/Rover v5
- Siemens SIM4KLE
- Delphi CR / Euro4 CR
- Delco Opel
- Fiat IAW 4SF/4DF/5SF
- Bosch Alfa JTS E4
- Bosch PSA M7.4.5
- Temic Mercedes CDI / Axor
- Sagem S2000/S3000
- Bosch Fiat ME7.9.x
- Bosch Alfa MED7.6.1
- Bosch PSA/Toyota M7.9.5
- Bosch Smart 2007 ME7.7
- Bosch VAG ME7.1.1 / ME7.5.x
- Visteon DCU
- Hitachi ECUs
- Siemens SIM82 / SIMTEC75/76
- Siemens EMS200
- Bosch PSG16
- Bosch TDI v2
- EFI Lotus
- Siemens PPD
- Delphi DCM3.x
- Bosch M3.x
- Bosch Opel ME7.x
- Generic 16-bit / 8-bit ECUs
Coverage is updated frequently. If your ECU is not listed, contact support and include your flash/EEPROM readout.
