Mileage Calibration Switch: Description and Operation
PURPOSEBecause of unique problems (such as oil injection) associated with controlling rotary engine emissions, Mazda incorporates a secondary air injection system with performance characteristics that vary with vehicle mileage. With switch input, PCME compensates for engine condition changes by altering distribution of secondary air in a manner designed to both reduce emissions and extend service life of components such as catalytic converters and oxygen sensor.
OPERATION
B+: Battery Positive Voltage:
Voltage at PCME terminal (1N) within the first two seconds after the ignition switch is turned to ON.