Great Wall GW491QE, Service Manual

Page: 99 / 222

EF.2-14
9.฀Camshaft฀position฀sensor฀(CAM)(MT20U)
(a)Function฀&principal
-Tnearby฀the฀camshaft,฀and฀works฀with฀signal฀wheel฀on฀camshaft.฀The
may฀measure฀the฀digital฀voltage฀signal฀via฀its฀sensor฀so฀as฀to฀determine฀the
cylinder฀on฀which฀engine฀is฀working,฀and฀to฀perform฀an฀one-to-one฀control;
-Wiring฀terminal A--signal,฀B--signal฀ground,฀C--+5V
-฀Installation:฀It’s฀installed฀nearby฀the฀camshaft.
10.฀Vehicle฀speed฀sensor฀ (VSS)
(a)Function฀&principal
Driving฀performance.
(b)Failure฀determination
Important฀note Either฀of฀following฀determinations฀may฀be฀concluded฀based฀on฀that฀the฀whole฀vehicle,฀its฀wire-harness,฀and
other฀systemparts&componentsarenormalinfunction.
-Failure฀diagnosed฀by฀the฀system฀may฀be฀read฀out฀from฀a฀Diagnosis฀Instrument;
-The฀form฀of฀fault฀signal฀includes:฀sensor฀damaged,฀looseness฀&disconnection฀of฀plug฀connectors,฀normal฀or฀artifical฀failure฀with฀wire-
harness
-The฀system฀will฀limit฀the฀driving฀performance฀of฀vehicle฀in฀an฀appropriate฀way,฀ie:฀worse฀Vehicle฀speed฀signal฀is฀provided฀by
instrumentations฀on฀vehicle;฀And฀ECU฀is฀able฀to฀receive฀digital฀square฀wave,฀whose฀amplitude฀value฀is฀within฀5 14฀volt;฀The฀number
of฀square฀wave฀per฀kilometer฀for฀vehicle฀may฀be฀determined฀when฀developing฀the฀system.฀And฀system฀has฀been฀designated฀to
improve฀the฀driving฀performance฀of฀whole฀vehicle฀via฀the฀signal.฀Besides,฀the฀driving฀mileage฀needs฀to฀be฀recorded.
(c)Characteristics฀of฀product
Accumulative฀mileage 80,000฀kilometers;
Limitation฀of฀engine฀rotating฀speed฀when฀sensor฀fails 2500r/min
Expiration฀for฀engine฀rotating-speed฀limit When฀exceeding฀70,000฀kilometer
(c)Characteristics฀of฀product
฀ ฀ ฀Working฀temperature฀ (-40 150)
฀ ฀ ฀Working฀voltage (4.3 13)V
฀฀฀Working฀clearance (0.3 2)mm
11.฀Knock฀sensor฀(KS)(MT20U)
(a)Function฀&principal
-The฀knock฀sensor฀is฀a฀piezoelectric฀type฀of฀vibrating฀sensor฀installed฀at฀a
sensitive฀position฀on฀engine฀unit,฀and฀is฀used฀to฀induce฀the฀knock฀produced฀by
engine.฀ECM฀will฀detect฀the฀intensity฀of฀knock฀via฀knock฀sensor฀so฀as฀to
modify฀the฀ignition฀lead-angle,฀effectively฀control฀the฀knock,฀and฀optimize฀the
dynamical฀performance฀of฀engine,฀the฀cost-effectivenss฀of฀fuel,฀and฀the฀exhaust
level.฀The฀system฀adopts฀a฀frequency-response฀typed฀knock฀sensor,฀and
ECM฀will฀filter฀its฀received฀signal;฀Due฀to฀a฀relatively฀weak฀sensor฀signal,฀the
leadin฀shall฀be฀of฀shielded฀wire
-Wiring฀terminal฀ A-signal,฀B-ground฀via฀shielded฀layer
-Installation The฀knock฀sensor฀is฀installed฀at฀a฀position฀sensitive฀to฀the
engine฀knock.
Delphi฀engine฀management฀systm Determination฀on฀the
principal฀/utility฀/failure฀of฀key฀system฀parts
(b)฀Failure฀determination
Important฀note Either฀of฀following฀determinations฀may
be฀concluded฀based฀on฀that฀the฀whole฀vehicle,฀its฀wire-
harness,฀and฀other฀system฀parts฀&components฀are฀normal
in฀function.
฀-฀฀Failure฀diagnosed฀by฀the฀system฀may฀be฀read฀out฀from฀a
Diagnosis฀Instrument
-Damage฀when฀over-voltage;฀the฀distance฀between฀sensor
and฀signal฀wheel฀is฀out฀of฀limit;
-The฀relative฀position฀of฀signal฀wheel฀to฀camshaft฀is฀incorrect,
or฀a฀displacement฀is฀produced.
ProCarManuals.com