P1639 Monitoring ADC — MAL
Описание ошибки P1639
Intialization of the background test is the first one carried out in the system. It therefore starts in the internal ROM and leads to supervisor identification by testing and initializing the external bus and testing the internal RAM. After the external RAM is tested and the checksum of the EPROM is calculated. After starting, A/D converter with all electric connections are monitored continuously by the ECM. 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. If the ECM A/D converter generates threshold value, the ECM judges this as a fault and DTC is set.
Возможная причина ошибки P1639
Faulty ECM