Engine Control Unit (Ecu): Notes

WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 1997 BMW Z3, 1997 BMW M3, 1997 BMW 840Ci, 1997 BMW 740iL, and 1997 BMW 740i. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Disconnect battery before removing Digital Motor Electronics (DME) ECU. Disconnecting battery will clear ECU Diagnostic Trouble Codes (DTCs). Retrieve DTCs before disconnecting battery. ECU stores certain basic driveability values. ECU also receives different input values, depending on engine condition, which are compared with stored values. ECU adaptive system compares input values with stored values. ECU replacement could cause poor engine performance before all values are adapted to engine condition. Before exchanging ECU, ensure engine is at normal operating temperature. Remove old ECU, install new ECU and operate vehicle at different RPMs.