Great Wall GW491QE, Руководство по обслуживанию

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EF.2-11
3.฀Absolute-pressure฀ sensor฀ for฀ inlet฀ manifold฀ (MAP
(ITMS-6)
(a)Function฀ &principal
The฀absolute-pressure฀sensor฀for฀inlet฀manifold฀(MAP)฀is฀used฀to฀measure฀the
pressue฀of฀inlet฀manifold,฀and฀ECU฀may฀use฀this฀signal฀to฀determined฀the฀air
amount฀inside฀engine฀and฀the฀load฀of฀engine.฀MAPsensor฀is฀composed฀of฀one
sealed฀flexible฀silicon฀chip,฀and฀relevant฀bridge-type฀electrical฀loops,฀with฀one
typical฀5V฀voltage฀applied฀to฀one฀end฀of฀electrical฀bridge;฀Whereby฀the฀change
of฀pressure฀results฀in฀a฀deformation฀of฀silicon฀chip,฀the฀resistance฀value฀will
change฀accordingly;฀On฀the฀other฀end฀of฀electrical฀bridge฀is฀0 5฀V฀output
signal,฀making฀direct฀proportion฀with฀input฀pressure.
Wiring฀terminal฀ A--signalground,B--pressuresignal,C--+5V.
Installation:฀It’s฀usually฀installed฀on฀the฀pressure฀stabilization฀cavity฀of
inlet฀manifold.
(b)Failure฀ determination
I mpor tant฀note
E ither฀of฀following฀determinations฀may฀be฀concluded
based฀on฀that฀the฀whole฀vehicle,฀its฀wire-harness,฀and฀other฀system฀parts
& components฀are฀normal฀in฀function.
-Pressure฀value฀read฀from฀a฀Diagnosis฀Instrument฀shall฀be฀consistent฀to฀the
actual฀value.
-When฀exterior฀cover฀is฀damaged฀or฀there’ s฀air฀leakage,฀the฀pressure฀will฀be
a฀fixed฀value
Converter
GND
Sensor
4.฀Inlet฀temperature฀sensor฀ ( M AT)(ITMS-6)
( a)Function฀ &principal
The฀inlet฀temperature฀sensor฀is฀used฀to฀test฀and฀measure฀the฀temperature฀of
air฀inside฀the฀engine฀cylinder;฀As฀any฀change฀of฀air฀temperature฀will฀directly
influence฀the฀density,฀it’ s฀regarded฀as฀one฀of฀significant฀parameters฀usable
to฀calculate฀the฀actual฀air฀amount฀inside฀the฀cylinder
(b)F ailur e฀ deter mination
Important฀note The฀temperature฀value฀read฀from฀a฀Diagnosis฀Instrument
shall฀be฀consistent฀to฀the฀actual฀value.฀T he฀temperature฀value฀has฀a฀large
deviation.฀When฀at฀normal฀temperature฀(20 30) ,฀its฀resistance฀value
will฀be฀(3510 2240) .
(c)C har acter istics฀of฀pr oduct
working฀voltage 5V DC
working฀temperature฀ (-40 135)
The฀schematic฀diagram฀of฀electric฀circuit:฀refer฀to฀the฀left฀figure
Delphi฀engine฀management฀systm-Determination฀on฀the
principal฀/utility฀/failure฀of฀key฀system฀parts
(c)Characteristics฀of฀product
Pressure฀range (15 102)฀kPa
Working฀temperature (-40 105)
Working฀voltage (5.0฀ ฀0.1)฀V
Working฀current 12฀mA฀(Max.)
Output฀ impedance <฀ 10฀
DC฀load 30฀k
฀(Min.) 51฀k ฀(recommended)
Output฀function E o=E r฀(0.01059P฀-฀0.10941)
(whereby T he฀unit฀of฀P฀is฀kPa)
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