PCM monitors errors through checksum. Every information consists of the combination of 0 and 1, checksum means summing up all values in a row. Thus, errors are recognized comparing checksum value and the memory value at PCM.
If the RAM in PCM has errors, PCM sets P0604 and MIL(Malfunction Indication Lamp) turns on.
Item | Detecting Condition | Possible cause |
DTC Strategy | ● Check internal CPU | ● Faulty PCM |
Enable Conditions | - | |
Threshold value | ● RAM has errors | |
Diagnosis Time | ● Continuous | |
MIL On Condition | ● 1 driving cycle |
