Diagnostic device for SPI-IAW16F Fiat car – Atmega8

This is a diagnostic interface for Fiats vehicles equipped with engines with a single point fuel injection (CFI), mainly IAW16F drives (seicento/cinquecento/punto). Full list of vehicle below.
Thanks to LCD used, the device does not need a computer to work. All the communicates and menu are displayed on the LCD 2x16 characters.



Interface communicates via 16-pin DLC connector inside the vehicle or 3-pin connector beneath the hood in ISO standard. You can navigate the menu with three buttons (next, confirm, back). The fourth button is used to reset the interface, so there was no need to disconnect the power after turning off the ignition and the desire to reconnect. The device is powered directly from the vehicle.
The whole system is based on a microcontroller Atmega8 clocked with a frequency of 11.0592MHz, programmed in C. Software uses a built-in USART to communicate with the vehicle.
Main function of the device:

• reading errors stored in RAM and EEPROM of the driver with a verbal description
• deleting errors stored in the engine control unit
• tracking the current parameters of the engine during operation
  • engine speed (rev / min)
  • fuel injection time (ms)
  • ignition timing (degrees)
  • pressure in the suction collector (kPa)
  • temperature of the air in the suction collector (degrees Celsius)
  • coolant temperature (degrees Celsius)
  • opening angle of the damper (degrees)
  • installation voltage (mV)
  • correction of the oxygen sensor voltage (%)
  • position of the stepper motor idle (step)
  • internal correction of the stepper motor settings (steps)
  • current correction of the stepper motor settings (steps)
• tests of actuators
  • test of the fuel pump for 30 seconds
  • test of the injector for 5 seconds
  • test of the ignition coils 1 or 2 for 5 seconds
  • test of the tank venting system valve for 7 seconds
  • speed limitation to 3750 rev / min
  • air conditioning for 30 seconds

The software was written so after any faulty user interventions, there would be no damage to the vehicle.
Atmega in the housing TQFP is on the bottom of the board. The other elements are in the housings for hole mounting on the top under the display.



List of supported vehicles:

• Fiat Cinquecento / Seicento with 900ccm engine and 1100ccm SPI to 2001 inclusive
• Fiat Punto 55 1100ccm SPI and 60 1200ccm SPI
• Tipo / Tempra 1.6 SPI Em.04
• Palio 1108 SPI
• Tipo 1372 SPI ECE 04
• Lancia Y 1.2 SPI

Link to owners page and film

Link to original thread – Urządzenie do diagnostyki Fiatów SPI-IAW16F - Atmega8