Mitsubishi 3000GT Service Manual page 121

MULTIPORT FUEL INJECTION - Troubleshooting
Check engine/malfunc-
tion indicator lamp
l If the sensor impressed voltage is abnormal, check the
wire for an open circuit or short-circuit to ground and
repair as necessary. If the wire is normal, replace the
engine control module and check again.
To check the voltage, use a digital voltmeter (or circuit
l
tester) as a rule.
[However, use an analog voltmeter for checking the power
transistor drive voltage.]
CHECK ENGINE/MALFUNCTION INDICATOR
LAMP
Among the on-board diagnostic items, a check engine/mal-
function indicator lamp comes on to notify the driver of the
emission control items when an irregurality is detected.
However, when an irregular signal returns to normal and the
engine control module judges that it has returned to normal,
the check engine/malfunction indicator lamp goes out.
Moreover, when the ignition switch is turned off, the lamp
goes out. Even if the ignition switch is turned on again, the
lamp does not come on until the irregularity is detected.
Here, immediately after the ignition switch is turned on, the
check engine/malfunction indicator lamp is lit for 5 seconds
to indicate that the check engine/malfunction indicator lamp
operates normally.
ITEMS INDICATED BY .THE CHECK ENGINE/
MALFUNCTION INDICATOR LAMP <Up to 1995
models>
Engine control module
Heated oxygen sensor
air flow sensor
Volume
Intake air temoerature sensor
Throttle position sensor
Engine coolant temperature sensor
Crankshaft position sensor
Camshaft position sensor
Barometric oressure sensor
Ignition timing adjustment signal
Injector
EGR system <California - Non Turbo, Turbo>
Ignition coil, ignition power transistor unit
Caution
The check engine/malfunction indicator lamp comes on
when the line of the ignition timing adjustment terminal
is shorted to ground. Therefore, the lamp also comes
on when the ignition timing adjustment terminal is
grounded to adjust the ignition timing, but this does not
show any abnormality.
TSB Revision