Great Wall GW491QE, Руководство по обслуживанию

Страница: 47 / 222

EF.1-28
Precautions฀to฀maintenance
-Do฀not฀dismantle฀the฀ECU฀casually฀during฀maintenance.
-Prior฀to฀dismantle฀of฀ECU,฀have฀the฀head฀of฀accumulator฀jar฀being฀removed฀for฀at฀least฀five฀minutes.
-Store฀the฀ECU฀securely฀after฀it฀is฀dismantled;
-It’s฀prohibited฀to฀install฀extra฀loops฀on฀the฀ECU฀connection฀line.
(h)฀Simple฀measurement฀method
Refer฀to฀the฀circuit฀diagram฀for฀UAES฀M1.5.4฀system
- after฀connection฀of฀joint ,฀read฀the฀record฀of฀engine฀failures฀via฀engine฀data฀line฀K;
- after฀disconnection฀of฀joint ,฀check฀whether฀ECU฀connection฀line฀is฀intact,฀and฀the฀main฀focus฀is฀to฀check฀whether฀the฀loop
of฀power฀supply฀/ground฀for฀ECU฀is฀normal;
-฀Check฀whether฀peripheral฀sensor฀is฀working฀normally,฀whether฀the฀output฀signal฀is฀reliable,฀and฀whether฀the฀loop฀is฀intact.
(a)Function฀
฀฀฀฀฀-฀฀฀฀Oil฀injection฀at฀multi-points฀as฀per฀the฀sequence
- Control฀the฀ignition
- Control฀the฀idle-speed
- Provide฀the฀sensor฀with฀power฀supply 5V/100mA
- Knock฀control
- Etyped฀closed-loop฀control,฀with฀self-adaptability;
- Control฀the฀carbon-canister฀valve
- Air-conditioner฀switch
- Engine฀fault฀indicator฀lamp
- Modification฀to฀the฀fixed฀quantity฀of฀fuel
- Output฀of฀engine฀rotating-speed฀signal TN฀signal
- Input฀of฀vehicle฀speed฀signal
- Failure฀self-diagnosis
- Control฀the฀carbon-canister฀valve
- Receive฀signal฀from฀the฀engine฀rotating-speed฀sensor
- Receive฀the฀engine฀load฀signal,฀etc.
(b)Symptom
Unstable฀idle-speed,฀bad฀acceleration,฀unable฀to฀start,฀too฀much฀high฀idle-speed,฀tail฀gas฀out฀of฀limit,฀start฀with
difficulty,฀air-conditioner฀failed,฀the฀oil฀injector฀control฀failed,฀flameout,฀etc.
(c)Cause฀of฀general฀failures
-The฀electrical฀overload฀on฀peripheral฀units฀results฀in฀a฀burning,฀damage฀or฀failure฀of฀parts฀and฀components฀inside฀ECU;
-Water฀inside฀ECU฀causes฀rust฀and฀corrosion฀on฀circuit฀board.
(d)฀Precautions฀to฀maintenance
-Do฀not฀dismantle฀the฀ECU฀casually฀during฀maintenance.
-Prior฀to฀dismantle฀of฀ECU,฀have฀the฀head฀of฀accumulator฀jar฀being฀removed฀for฀at฀least฀one฀minute.
-Store฀the฀ECU฀securely฀after฀it฀is฀dismantled;
-It’s฀prohibited฀to฀install฀extra฀loops฀on฀the฀ECU฀connection฀line.
(e)Simple฀measurement฀method
฀- after฀connection฀of฀joint ,฀read฀the฀record฀of฀engine฀failures฀via฀engine฀data฀line฀K;
฀- after฀disconnection฀of฀joint ,฀check฀whether฀ECU฀connection฀line฀is฀intact,฀and฀the฀main฀focus฀is฀to฀check฀whether฀the฀loop
of฀power฀supply฀/ground฀for฀ECU฀is฀normal;
-Check฀whether฀the฀peripheral฀sensor฀is฀working฀normally,฀whether฀the฀output฀signal฀is฀reliable,฀and฀whether฀its฀loops are฀intact;
-Check฀whether฀the฀actuator฀is฀working฀normally,฀and฀whether฀its฀loops฀are฀intact;
-Finally,฀perform฀a฀test฀after฀ECU฀is฀changed.
United฀Electronic฀engine฀management฀system-Analysis฀of฀function฀/principal฀/
failure฀for฀system฀parts฀&components
17.฀ Electronic฀ controller฀ ECU M 7.9.7
ProCarManuals.com