Briggs & Stratton Vanguard 430000, Руководство пользователя

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10
Heated Oxygen Sensor
The oxygen sensor (Figure 10) is the last in-line
device to the ECU, providing information about the
effectiveness of the ECU’s output commands. The
oxygen sensor is placed in the exhaust system to
detect whether the engine is operating in a rich or
lean state.
The sensor creates an electrical signal when it
senses a difference in the level of oxygen in the
exhaust compared to the outside atmosphere.
An integral heating element brings the sensor up to
operating temperature quickly.
Figure 10
Ignition Coil
The ECU triggers the ignition coil (Figure 11) to fire,
sending voltage to each spark plug when needed.
Figure 11
Malfunction Indicator Light (MIL)
If the self-diagnostic feature detects a fault, the fault
code is displayed on the malfunction indicator lamp
(MIL) (Figure 12) and is recorded in the ECU. The
fault is stored until the memory is reset.
Figure 12
Manifold Absolute Pressure (MAP) Sensor
The manifold absolute pressure (MAP) sensor
(Figure 13) measures the amount of vacuum in the
intake manifold. This sensor uses a constant
absolute pressure to eliminate the effects of
changing atmospheric conditions.
The sensor uses a 5 volt input reference and, as
pressure changes, it increases or decreases the
amount of voltage returned to the ECU, which
mathematically determines the engine load and
regulates the amount of fuel to be injected.
Figure 13