Great Wall GW491QE, Руководство по обслуживанию

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EF.2-27
Precautions฀to฀the฀use฀/service฀/troubleshooting฀of฀electrical฀injection฀system
(c)The฀leadin฀of฀spark฀plug฀shall฀not฀be฀pulled฀out฀when฀checking฀whether฀the฀ignition฀system฀is฀working,฀as฀the฀injection฀nozzle฀is
still฀working,฀and฀some฀petrol฀spraying฀out฀yet฀not฀being฀used฀will฀be฀combusting฀rapidly฀inside฀three-way฀catalytic฀converter฀ and
cause฀damages;
(d)Do฀not฀dismantle฀system฀electrical฀parts฀&components฀when฀ignition฀switch฀is฀connected฀to฀avoid฀damages;
(e)When฀checking฀the฀replacement฀of฀ECU,฀please฀be฀noted฀that฀the฀vehicle฀shall฀be฀equipped฀with฀computer-based฀theft฀detector;฀If
so,฀ECU฀may฀be฀replaced฀after฀a฀power฀cut฀made฀to฀theft฀detector,฀otherwise,฀new฀ECU฀will฀be฀locked฀by฀theft-prevention฀function,
and฀can฀not฀work฀on฀other฀vehicles;
(f)Anti-interference฀spark฀plug฀plus฀high-tension฀wiring฀shall฀be฀used฀within฀system,฀if฀not,฀negative฀effect฀may฀be฀brought฀to ฀the
ignition-coil฀drive฀mode฀inside฀ECU,฀and฀ECU฀may฀even฀be฀damaged.
(g)When฀changing฀fuel฀inlet฀/return฀pipe,฀use฀petrol฀pipe฀which฀can฀withstand฀a฀bursting฀pressure฀greater฀than฀2Mpa;
(h)Method฀like฀‘use฀needle฀to฀punch฀wire-harness’฀shall฀not฀be฀used฀to฀check฀the฀system฀current฀signal;
(i)Always฀remember฀to฀disconnect฀accumulator฀jar฀from฀ECU฀connector฀when฀exterior฀electrical฀system฀tools฀are฀applied฀for฀welding
purpose
(j)During฀installation฀or฀dismantling฀of฀components฀within฀the฀electrical-injection฀system,฀severe฀knocks฀or฀strikes฀against฀components
are฀prohibited;
(k)Any฀check฀or฀test฀shall฀not฀proceed฀when฀ECU฀cover฀is฀opened฀to฀avoid฀greater฀damage.
Any฀loss฀produced฀after฀ECU฀is฀opened฀will฀not฀be฀compensated;
(l)When฀changing฀or฀dismantling฀the฀oxygen฀sensor,฀it’s฀unallowable฀to฀apply฀any฀sealant฀to฀the฀threaded฀part฀of฀oxygen฀sensor฀to
avoid฀burning฀and฀damage;
(m)It’s฀unallowable฀for฀fuel฀pump฀to฀run฀for฀a฀long฀term฀period฀when฀it฀contains฀no฀petrol,฀neither฀to฀run฀in฀air฀even฀when฀its฀contains
petrol;
(n)If฀any฀breakage฀is฀found฀in฀loop,฀quality฀insulation฀tape฀shall฀be฀used฀for฀wrapping฀purpose฀during฀maintenance฀to฀avoid฀greater
loss.
(o)Upon฀the฀confirmation฀on฀damage฀on฀electrical-injection฀components,฀they฀shall฀be฀changed฀accordingly฀in฀normal฀case฀as฀most฀of
them฀are฀unable฀to฀be฀restored.
Tr oubleshooting
1.฀Solutions฀to฀failure
(a)Query฀diagnostic฀method
-When฀query,฀you฀shall฀be฀earnest,฀conscientious,฀amiable,฀and฀attentive฀in฀listening.
-The฀query฀shall฀be฀made฀from฀an฀integral฀view฀and฀focus฀on฀key฀points;฀and฀you฀need฀to฀further฀understand฀the฀history฀and฀the
frequency฀of฀symptom.
-Based฀on฀the฀symptom฀known฀from฀vehicle฀owner฀when฀some฀failure฀is฀produced,฀an฀analysis,฀judge,฀and฀initial฀determination฀may
be฀concluded.
(b)Observe฀diagnostic฀method
-The฀observation฀shall฀be฀based฀on฀the฀symptom,฀and฀consider฀the฀whole฀system฀and฀some฀focus,฀and฀proceed฀as฀per฀a฀certain
sequence
-An฀exterior฀inspection฀is฀needed฀to฀check฀the฀water฀/฀air/fuel/฀electrical฀loop฀of฀vehicle฀which฀has฀failure
- To฀find฀the฀cause฀of฀failure,฀some฀instruments฀or฀instrumentations฀applicable฀to฀vehicle฀may฀be฀used฀during฀the฀inspection.
฀-฀A฀judge฀shall฀also฀be฀made฀based฀on฀a฀careful฀observation฀on฀the฀symptom,฀fault฀code,฀sound,฀etc.฀when฀some฀failure฀is฀฀produced.
(c)฀฀Component฀displacement฀method
-New฀component฀will฀be฀used฀to฀take฀the฀place฀of฀original฀component฀which฀may฀have฀possible฀failures;
-The฀original฀component฀which฀may฀have฀possible฀failures฀will฀be฀installed฀on฀another฀good฀vehicle฀for฀a฀further฀verification;
-The฀displacement฀of฀some฀component฀shall฀be฀supported฀by฀appropriate฀reasons,฀and฀can฀฀not฀be฀made฀on฀blindness.
(d)฀฀Case฀application฀method
-Based฀on฀results฀concluded฀from฀typical฀cases,฀direct฀search฀the฀cause,฀remove฀the฀failure,฀and฀reduce฀unnecessary฀inspections
-This฀method฀is฀only฀applicable฀to฀the฀same฀failure฀produced฀on฀the฀same฀model฀of฀vehicle฀or฀the฀same฀type฀of฀system
-This฀method฀is฀not฀applicable฀to฀common฀failures,฀which฀have฀a฀similar฀symptom฀yet฀caused฀by฀various฀causes.
(e)฀฀Experience฀method
-Based฀on฀previous฀results฀gained฀from฀the฀settlement฀of฀various฀failures,฀experiences฀may฀be฀accumulated฀gradually,฀and฀the
capability฀to฀solve฀the฀trouble฀may฀be฀increased฀as฀well
-Depending฀on฀the฀similarity฀and฀difference฀of฀symptoms,฀a฀determination฀may฀be฀concluded฀accordingly฀by฀applying฀previous
experiences฀in฀a฀flexible฀way
-Existing฀experiences฀may฀be฀optimized฀by฀make฀a฀conclusion฀from฀the฀settlement฀of฀special฀or฀typical฀failures,฀and฀recording฀ the
successes฀and฀mistakes฀in฀the฀course฀of฀settlement.
(f)฀Logic฀thinking฀method
-A ฀logic฀thinking฀method฀may฀be฀adopted฀to฀analyze฀the฀failure฀and฀find฀out฀the฀failure฀points฀in฀accordance฀with฀the฀working
principal฀of฀testing฀data฀and฀system
-It’ s฀required฀to฀be฀familiar฀with฀the฀working฀principal฀and฀function฀of฀engine,฀the฀electrical-injection฀system,฀and฀system฀components
-For฀some฀failures,฀a฀logic฀thinking฀& analysis฀is฀much฀compulsory.
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