The ECM function switches valid for the whole driving cycle are selected in the initialization of the background test and are made available in the corresponding messages.
An ECM ROM malfunction is detected by using a checksum technique for verifying data.
Digital data is composed of zeros and ones. A checksum is the total of all ones in a string of data.
By comparing the checksum value with a stored value, a malfunction can be detected.
In case of the EEPROM error, the engine symptoms will occur the running engine stall and the starting impossible.
If the ECM is generated threshold value, the ECM judged this as a fault and DTC is set.
Item | Detecting Condition | Possible Cause |
DTC Strategy | ● ECM check | ● Faulty ECM |
Enable Conditions | ● Ignition on | |
Threshold Value | ● EEPROM - Write error | |
Diagnostic Time | ● 0 sec | |
MIL Fuel Limit Fuel Cut EGR Off | ● Yes ● No ● Yes ● No |
