Mitsubishi Electric Lancer Evolution-VII Workshop Manual page 1148

CONFIRMING 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
MUT-II, an effective troubleshooting can be performed.
NOTE
If mulfunctions have been detected in multiple systems, engine-ECU stores one malfunction only, which
has been detected first.
Item No. Data item
21 Engine coolant temperature
sensor
22 Crank angle sensor
24 Vehicle speed
FAIL-SAFE FUNCTION REFERENCE TABLE
When the main sensor malfunctions are detected by the diagnosis function, the vehicle is controlled
by means of the pre-set control logic to maintain safe conditions for driving.
Malfunctioning item
Air flow sensor
Intake air temperature
sensor
Throttle position
sensor
Engine coolant
temperature sensor
Camshaft position
sensor
Barometric pressure
sensor
Detonation sensor
Alternator FR terminal
MPI - MPI -
Unit/State
_C
r/min
km/h
Control contents during malfunction
1. Uses the throttle position sensor signal and engine speed signal (crank angle sensor
signal) to take reading of the basic injector drive time and basic ignition timing from
the pre-set mapping.
2. Fixes the idle speed control servo in the appointed position so idle control is not
performed.
Controls as if the intake air temperature is 25_C.
No increase in fuel injection amount during acceleration due to the throttle position sensor
signal.
1. Controls as if the engine coolant temperature is 80_C.
(Even after sensor signal is correctly recovered, continues until the ignition switch
is set to the "LOCK" (OFF) position.)
2. Rotates radiator fan and condenser fan at high speed.
1. Inject all fuel cylinders simultaneously. (However, when the No.1 cylinder top dead
centre is not detected at all after the ignition switch is turned to "ON" position.)
2. Shuts off fuel supply after 4 seconds have passed since a failure was detected.
(However, when the No.1 cylinder top dead centre is not detected at all after the
ignition switch is turned to "ON" position.)
Controls as if the barometric pressure is 101 kPa.
Switches the ignition timing from ignition timing for super petrol to ignition timing for standard
petrol.
Does not control the output of the alternator according to an electrical load. (works as a
normal alternator)
Troubleshooting Troubleshooting
Item No. Data item
81 Learn value
82 Feedback
87 Engine load
13A-11
Unit/State
%
%
%