Fuel And Emissions System Descriptions; Elestronic Control System - Honda S2000 Service Manual

Fuel and Emissions Systems
System Descriptions
Elestronic Control System
The functions of the fuel and emissions control systems are managed by the engine control module (ECM).
Fail-safe Function
When an abnormality occurs in the signal from a sensor, the ECM ignores the signal and assumes a pre-programmed
value for the sensor that allows the enqine to continue to run.
Back-up Function
When an abnormality occurs in the ECM, the injectors are controlled by a back-up circuit independent ofthe system to
p e r m i t m i n i m a l d r i v i n g .
Self-diagnosis
When an abnormality occurs in the signal from a sensor, the ECM supplies ground for the MIL and stores the DTC in
erasable memory. When the ignition is first turned ON (ll), the ECM supplies ground for the MIL for 2 seconds to check
t h e M I L b u l b c o n d i t i o n .
Two Driving Cycle Detection Method
To prevent false indications, the "two driving cycle detection method" is used for some self-diagnostic functions.
When an abnormality occurs, the ECM stores it in its memory. When the same abnormality recurs after the ignition
switch is turned OFF and ON (ll) again, the ECM turns on the l\411.
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