Mazda CX-5 U0100: Lost Communication with ECM/PCM “A”
U0100 is a generic diagnostic trouble code, meaning it has the same definition for any vehicle made in the 1996 model year or newer (including the Mazda CX-5). This code tells you that communication has been lost between the ECM/PCM (main computer) and a particular control module has been completely lost. When a vehicle has … Read more