DTC B1657 indicates that the option bit portion of the instrument cluster EEPROM has an unrecoverable error. The option bit portion of the instrument cluster EEPROM stores the manufacturing information.

DTC B1657 sets when the instrument cluster detects an error in the option bit portion of the EEPROM during a diagnostic system self-test.

When DTC B1657 sets, the following acions may occur:

Replace the instrument cluster. The EEPROM is not serviceable. If DTC B1657 sets, perform the following actions:

1. Refer to the most recent service information in order to obtain the approximate vehicle mileage.
2. Contact an authorized Delco® service center.
3. Return the faulty instrument cluster to the service center.