Suzuki GRAND VITARA JB416, Service Manual

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Engine General Information and Diagnosis: 1A-3
ECM and malfunction indicator lamp (1) operate as
follows.
• Malfunction indicator lamp (1) lights when the ignition
switch is turned ON (but the engine at stop) with the
diagnosis switch terminal ungrounded regardless of
the condition of Engine and Emission control system.
This is only to check the malfunction indicator lamp (1)
in the combination meter and its circuit.
• If the above areas of Engine and Emission control
system is free from any trouble after the engine start
(while engine is running), malfunction indicator lamp
(1) turns OFF.
• When ECM detects a trouble which has occurred in
the above areas, it makes malfunction indicator lamp
(1) turn ON while the engine is running to warn the
driver of such occurrence of trouble and at the same
time it stores the trouble area in ECM back-up
memory. (The memory is kept as it is even if the
trouble was only temporary and disappeared
immediately. And it is not erased unless the power to
ECM is shut off for specified time or it is cleared by
SUZUKI scan tool (2).)
In addition, DTC can be read by not only using
SUZUKI scan tool but also displayed on odometer (5)
of the combination meter. (i.e. when diagnosis switch
terminal (3) is grounded with a service wire (4) and
ignition switch is turned ON.) For further detail of the
checking procedure, refer to “DTC Check: in related
manual”.
Warm-Up Cycle
A warm-up cycle means sufficient vehicle operation such
that the coolant temperature has risen by at least 22
°
C
(40
°
F) from engine starting and reaches a minimum
temperature of 70
°
C (160
°
F).
Driving Cycle
A “Driving Cycle” consists of engine startup and engine
shutoff.
2 Driving Cycle Detection Logic
The malfunction detected in the first driving cycle is
stored in ECM memory (in the form of pending DTC) but
the malfunction indicator lamp does not light at this time.
It lights up at the second detection of same malfunction
also in the next driving cycle.
Pending DTC
Pending DTC means a DTC detected and stored
temporarily at 1 driving cycle of the DTC which is
detected in the 2 driving cycle detection logic.
6. Diagnosis connector
1
5
6
2
3
4
I5JB0A110003-01