Mitsubishi 1989-1993 GALANT Service Manual page 445

FUEL SYSTEM <DOHC> -
INSPECTION
Using Scan tool
Function Item No.
Data reading 44
Normal waveform
ov
Normal waveform
HARNESS INSPECTION
Harness side
connector
connector
Data display
Inspection conditions
Ignition
. Engine: warm
advance
. Timing light: set
(Use the timing light to
check the actual ignition
timing.)
Using Oscilloscope
1. Primary signal of ignition coil
(1) Run the engine at an idle revolution speed.
(2) Connect the probe to oscilloscope pick-up point 1 as
2. Control signal of ignition power transistor
Measure the power supply voltage of
-0
the ignition coil.
. Connector: Disconnected
0
. Ignition switch: ON
Battery positive voltage
Check for an open-circuit, or a short-
control
circuit to ground, between the engine
module
control module and the ignition coil.
harness
side
connector
tor: Disconnected
nected
TSB Revision
Engine condition
750 rpm (idling)
2,000 rpm
shown in the circuit diagram, and check the primary
signal of the ignition coil.
shown in the circuit diagram, and check the control
signal of the ignition power transistor.
Voltage (VI
I
Standard value
5-15" BTDC
32 - 4 1 "BTDC
Ignition
switch)
Repair the
harness.