Mitsubishi Eclipse 1990 Service Manual page 396

FAIL-SAFE-BACUP FUNKTION
When the PCM detects the following malfunction (s), the PCM carries out' fail safe/back-up
addition, the corresponding DTC number (s) can be identified by using the scan tool.
Diagnostic item
No cam signal at PCM
Throttle position sensor
age low
Throttle position sensor
age high
Engine coolant temperature
(ECT) sensor voltage too low
Engine coolant temperature
(ECT) sensor voltage too
high
Upstream stays at
center
No vehicle speed sensor
I
signal
I MAP sensor voltage too low
I sensor voltage too high
change in MAP from start
0 run
I ntake air temperature sensor
roltage low
I ntake air temperature sensor
roltage high
sensor
Jpstream shorted to
1
temperature sensor
out of limit
speed fan control relay
Jpstream response
1
oltage
stays at
enter
ENGINE (NON-TURBO)>
Control during malfunction
The PCM uses the crankshaft position sensor signal
timing, etc. (Accordingly, normal sequential
out.)
The PCM uses the value calculated from the MAP sensor signal instead of the
valve opening angle (voltage).
The PCM uses the value calculated from the MAP sensor signal instead of the throttle
valve opening angle (voltage).
The PCM uses the default value
temperature.
The PCM operates the radiator fan.
The PCM carries out open loop control.
The PCM uses the default value
temperature.
The PCM operates the radiator fan.
The PCM carries out open loop control.
The PCM carries out open loop control.
The PCM controls the engine as if the vehicle speed were 0 mph.
The PCM uses the value calculated from the throttle position sensor and the engine
speed signals instead of the MAP value
The PCM uses the value calculated from the throttle position sensor and the engine
speed signals instead of the MAP value
The PCM uses the value calculated from the throttle position sensor and the engine
speed signals instead of the MAP value
The PCM uses the engine coolant temperature instead of the intake air temperature.
The PCM uses the engine coolant temperature instead of the intake air temperature.
The PCM retards ignition timing according to the knock sensor signal.
The PCM carries out open loop control.
The PCM uses the default value
The PCM turns on the high speed fan control relay instead of the low speed fan
relay
The PCM carries out open loop control.
to The PCM carries out open loop control.
The PCM carries out open loop control.
TSB Revision
Troubleshooting
Mode) TABLE
as the battery temperature.
control fuel
fuel injection may not be
as the engine
as the engine