Maintenance Manual for Chery·Windcloud Marelli EFI System
6. Electronic Control Unit (ECU)
Purpose: ECU is the core of electronic
engine control system. Sensors sent various
signals to ECU for electric control, and
then ECU controls operations of fuel
injector and ignition coil, etc. after internal
calculation, thus controlling working of
engine.
Normal operation voltage: 9-16V
Composition: it has shielded casing and
printed circuit board, which integrates lots
of electronic control units for the control of
EFI system.
Installation: to be fixed by the support of
bracket under pilot trench of front
windshield. Pay attention to waterproofing.
ECU
Functions:
Multipoint sequential injection
Controlling ignition
Idle speed control
Independent knocking control on
cylinder-by-cylinder basis (knock sensor);
Providing sensors with power supply:
5V/100mA
λclosed-loop control with self-adaptation
Controlling carbon canister control valve
Air conditioning switch
Engine-fault indicating lamp
Fuel quantitative correction
Engine speed signal output
Speed signal input
Accepting engine load signal
Troubleshooting: due to the fact that ECU
(electric control unit) has low failure rate, so
generally it is not advisable to replace ECU
for troubleshooting on any problem. Failure
of components such as periphery circuit and
sensors shall be checked and solved firstly.
Do not replace ECU until all periphery
components are confirmed to be fault-free.
Caution: poor internal contact is common
with ECU connector of A-series EFI system.
Connector problems are not easy to be
detected from the appearance of connector.
It is recommended that the detecting probe
be inserted from the back of connector
without breaking of wires. Broken wires
shall be covered by a layer of glass cement
and then proof fabric.
6
To Next Page
Loading...
Need help?
General
