ECU Recovery
System Modes
The ECU can run in one of two modes: reprogramming mode and application mode. In reprogramming mode, the ECU can be reprogrammed using a CAN Calibration Protocol (CCP) tool. In application mode, the ECU runs the loaded software.
What is FEPS?
The Flash and EEPROM Programming Signal (FEPS) signals the OpenECU firmware to enter reprogramming mode during startup. It is activated by applying voltage to the FEPS pin on the ECU. Refer to the Technical Specification tech-spec for pin details and supported FEPS modes.
Positive FEPS Mode
Positive FEPS mode starts when the voltage on the FEPS pin exceeds the positive FEPS threshold. It attempts to use the CAN Calibration Protocol (CCP) settings specified in the pre-loaded application.
Reprogramming with positive FEPS using two power supplies:
Connect ECU power, ground, and ignition to one supply and set its voltage within the ECU’s operating range. Turn off the supply.
Connect the FEPS wire to another power supply set to a voltage greater than the positive FEPS threshold. Turn this supply on.
Turn on the supply powering the ECU. Verify the module is in positive FEPS mode using Flash Code Output.
Reprogram the ECU using the current CCP settings.
Negative FEPS Mode
Negative FEPS mode starts when the FEPS pin voltage is below the negative FEPS threshold. This mode uses default CAN Calibration Protocol (CCP) settings.
CCP setting |
Default value |
|---|---|
CRO message identifier |
1785 |
DTO message identifier |
1784 |
Station address |
0 |
CAN bus identifier |
CAN 0 |
CAN bus baud-rate |
250kBps or 500kBps |
Note
Refer to the User Guide to determine the default CAN baud-rate.
Reprogramming with negative FEPS using batteries:
