Suzuki GRAND VITARA JB416, Service Manual

Page: 22 / 474

1A-4 Engine General Information and Diagnosis:
Freeze Frame Data (Vehicle Not Equipped with
Diagnosis Connector)
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 each 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 each 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.
Freeze frame data clearance:
The freeze frame data is cleared at the same time as clearance of DTC.
[A]: 1st or 2nd in parentheses here represents which position in the order
the malfunction is detected.
[A]
I3RB0A110002-01
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
P0401 (EGR)
detected Data at P0401
detection Data at P0401
detection
— —
2
P0171 (Fuel system)
detected Data at P0171
detection Data at P0401
detection Data at P0171
detection
—
3
P0300 (Misfire)
detected Data at P0171
detection Data at P0401
detection Data at P0171
detection Data at P0300
detection
4
P0301 (Misfire)
detected Data at P0171
detection Data at P0401
detection Data at P0171
detection Data at P0300
detection