MPI <4G1> -
Troubleshooting
13A-7
FREEZE FRAME DATA
When the engine-ECU 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.
Displayed items of freeze frame data are shown in the
following:
DISPLAYED 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 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: P0421
D
Oxygen sensor: P0130
D
Oxygen sensor heater: P0135, P0141
