Page 2579 - Foton Workshop Manual - Sauvana

DIAGNOSIS-ENGINE CONTROL SYSTEM 62-527
DIAGNOSTIC INSTRUMENT APPLICATION

1. Fault code reading
Notice：
•Failure is detected by engine control system and stored in ECU. The system failurecan be
current or historical. 62
•If the battery voltage is too low, detection code of ECUcannot be normally output; and you
must check the battery voltage before the test, thevoltage is about12V.
•When the battery orthe ECUconnector is disconnected, the fault code stored in the ECUis
cleared .
•Special detection tool is used to read engine fault code.
•Before connecting or disconnecting the instrument, the ignition switch is ensured in the
"LOCK" position.
With the function of failure self-diagnosis, once detecting the EFI system failure, ECUwill
generate corresponding fault code and store it in memory, automatically entering the
different failure protection strategiesaccording to the failure level. In most cases, failure
protection strategies can still keep theengine working in a way that reduces power. In a few
extremely serious failures, failure protection strategy will stop the injection and the work
ofengine.
Failure is read by special diagnostic instrument:
(a). Turn the ignition switch to "ON". If the trouble lamp is on, it indicates that the there
are system failures.
(b). The interface of special failure diagnosis instrument is connected to the diagnosis
interface.
(c). The fault code is read in diagnosis instrument, that is "fault code" displayed on the
diagnostic instrument.
(d). According to the failure cause showed in fault code, the wiring harness of
corresponding components should be checked; or the relevantcomponents should
be replaced.
(e). After removing the failure and eliminating original fault code with failure diagnostic
instrument, the fault code should be read once again. No fault code is ensured to do
the following work.
2. Fault code removal
(a). Firstly the fault code should be removed before confirmation of some accidental
failures. If the system fails, the fault code will alwaysexist until the failure is removed.
(b). Diagnostic instrument is connected to system to remove the stored fault code in
current control unit.
3. Data flow readin
You can check the data values of switches, sensors, actuators, and other parts
without removing any parts by reading the data flow displayed on the diagnostic
instrument, Reading the data flow as a first step in failure removal isone way to
shorten the diagnostic time.

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