MPI <4G9> -
Troubleshooting
13A-88
FREEZE FRAME DATA
When the engine-ECU <M/T> or engine-A/T-ECU <A/T>
detects a malfunction and stores a diagnosis code, it also
stores a current status of the engine. This function is called
“Freeze frame data.” By analyzing this “freeze frame” data
with the MUT-
II
, an effective troubleshooting can be
performed.
The display items of freeze frame data are shown below.
Display item list
Data item
Unit
Engine coolant temperature sensor
_
C
Engine speed
r/min
Vehicle speed
km/h
Long-term fuel compensation (long-term
fuel trim)
%
Short-term fuel compensation (short-term
fuel trim)
%
Fuel control condi- Open loop
OL
tion
Closed loop
CL
Open loop owing to
drive condition
OL-DRV.
Open loop owing to
system malfunction
OL-SYS.
Closed loop based
on one oxygen sen-
sor
CL-H02S
Calculation load value
%
Diagnosis code during data recording
-
NOTE
If malfunctions have been detected in multiple systems, store
one malfunction only, which has been detected first.
READINESS TEST STATUS
The engine-ECU <M/T> or engine-A/T-ECU <A/T> monitors
the following main diagnosis items, judges if these items are
in good condition or not, and the stores its history. This
history can be read out by using MUT-
II
. (If the ECU has
judged a item before, the MUT-
II
displays “Complete.”)
In addition, if diagnosis codes are erased or the battery
cable is disconnected, this history will also be erased (the
memory will be reset).
D
Catalyst: P0420
D
Oxygen sensor: P0130
D
Oxygen sensor heater: P0135, P0141
