Suzuki Liana RH413, Service Manual

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1A-3 Engine General Information and Diagnosis:
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.
Freeze frame data
ECM stores the engine and driving conditions (in the form of data as shown in the figure) at the moment of the
detection of a malfunction in its memory. This data is called “Freeze frame data”.
Therefore, it is possible to know engine and driving conditions (e.g., whether the engine was warm or not, where the
vehicle was running or stopped, where air / fuel mixture was lean or rich) when a malfunction was detected by
checking the freeze frame data. Also, ECM has a function to store each freeze frame data for three different
malfunctions in the order as the malfunction is detected. Utilizing this function, it is possible to know the order of
malfunctions that have been detected. Its use is helpful when rechecking or diagnosing a trouble.
Priority of freeze frame data:
ECM has 4 frames where the freeze frame data can be stored. The first frame stores the freeze frame data of the
malfunction which was detected first. However, the freeze frame data stored in this frame is updated according to the
priority described. (If malfunction as described in the upper square “1” is detected while the freeze frame data in the
lower square “2” has been stored, the freeze frame data “2” will be updated by the freeze frame data “1”.)
In the 2nd through the 4th frames, the freeze frame data of each malfunction is stored in the order as the malfunction
is detected.
These data are not updated.
Shown in the table are examples of how freeze frame data are stored when two or more malfunctions are detected.
[A]: An example of freeze frame data
[B]: 1st, 2nd or 3rd in parentheses here represents which position in the order the malfunction is detected.
Priority Freeze frame data in frame 1
1 Freeze frame data at initial detection of malfunction among misfire detected (P0300 – P0304), fuel
system too lean (P0171) and fuel system too rich (P0172)
2 Freeze frame data when a malfunction other than those in “1” is detected
Malfunction detected order
Frame
Frame 1 Frame 2 Frame 3 Frame 4
Freeze frame data to
be updated
1st freeze frame
data
2nd freeze frame
data
3rd freeze frame
data
No malfunction No freeze frame data
1 P0400 (EGR)
detected
Data at P0400
detection Data at P0400
detection
— —
2 P0171 (Fuel system)
detected
Data at P0171
detection Data at P0400
detection Data at P0171
detection
—
3 P0300 (Misfire)
detected
Data at P0171
detection Data at P0400
detection Data at P0171
detection Data at P0300
detection
4 P0301 (Misfire)
detected
Data at P0171
detection Data at P0400
detection Data at P0171
detection Data at P0300
detection
I2RH01110003-01