Suzuki Jimny Service Manual page 364

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-7
DRIVING CYCLE
A "Driving Cycle" consists of engine startup and engine shutoff.
2 DRIVING CYCLES DETECTION LOGIC
The malfunction detected in the first driving cycle is stored in
ECM memory (in the form of pending DTC and freeze frame data)
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.
FREEZE FRAME DATA
ECM stores the engine and driving conditions (in the from of data
as shown in the figure) at the moment of the detection of a mal-
function 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.
[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 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 below.
(If malfunction as described in the upper square "1" below 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".)
PRIORITY FREEZE FRAME DATA IN FRAME 1
Freeze frame data at initial detection of mal-
function among misfire detected (P0300 –
1
P0304), fuel system too lean (P0171) and fuel
system too rich (P0172)
Freeze frame data when a malfunction other
2
than those in "1" above is detected