Honda ACCORD HYBRID 2005 Service Manual page 276

Fuel and Emissions Systems
S y s t e m D e s c r i p t i o n ( c o n t ' d )
Intake Air Temperature (IAT) Sensor 2
The IAT sensor 2 is a temperature dependent resistor
(thermistor). The resistance of the thermistor decreases
as the intake air temperature increases.
TERMINAL
THERMISTOR
Knock Sensor
The knock control system adjusts the ignition t i m i n g to
minimize knock.
TERMINAL
PIEZO CERAMIC
E L E M E N T
DIAPHRAGM
Malfunction Indicator Lamp (MIL) Indication (In relation
to Readiness Codes)
The vehicle has certain "readiness c o d e s " that are part
of the on-board diagnostics for the emissions systems.
If the vehicle's battery has been disconnected or gone
dead, if the DTCs have been cleared, or if the PCM has
been reset, these codes are reset. In s o m e states, part
of the emissions testing is to make sure these codes are
set to complete. If all of t h e m are not set to complete,
the vehicle may fail the test, or the test cannot be
finished.
To check if the readiness codes are set to complete,
turn the ignition switch ON (II), but do not start the
engine. The MIL will come on for 15—20 seconds. If it
then goes off, the readiness codes are complete. If it
flashes five times, one or more readiness codes are not
complete. To set each code, drive the vehicle or run the
engine as described in How to Set Readiness Codes
(see page 11-63).
Manifold Absolute Pressure (MAP) Sensor
The MAP sensor converts m a n i f o l d absolute pressure
into electrical signals to the PCM.
O-RING
Mass Air Flow (MAF) Sensor/intake Air Temperature
(IAT) Sensor 1
The MAF sensor/IAT sensor 1 contains a hot w i r e and a
thermistor. It is located in the intake air passage. The
resistance of the hot w i r e and t h e r m i s t o r change due to
intake air temperature and air f l o w . The control circuit
in the MAF sensor controls the current to keep the hot
w i r e at a set temperature. The current is converted to
voltage in the control circuit, then output to the PCM.
H O T W I R E
IAT S E N S O R 1
(THERMISTOR)
11-36