MPI – Troubleshooting
13-63
ENGINE-ECU INSPECTION
TERMINAL VOLTAGES
Engine ECU connector
Terminal
No.
Check item Check condition (Engine condition) Normal condition
1 No.1 injector While engine is idling after having been warmed up,
suddenly depress the accelerator pedal
Momentarily drops
f
14 No.2 injector
su
en
y
epress
e acce
era
or pe
a
. s
g
y
rom
–
.
2 No.3 injector
15 No.4 injector
3 Fuel pressure control
Ignition switch: ON System voltage
va
ve
Engine: Cranking to idling (within about two minutes) 0 – 3 V to sytem
voltage
4 Stepper motor coil (A1) Engine: Immediately after engine has been started
f
Changes repeatedly
f
17 Stepper motor coil (A2)
or warm
ng up
rom sys
em vo
age
to 0 – 6 V and from 0
5 Stepper motor coil (B1)
–
to system
voltage.
18 Stepper motor coil (B2)
6 Secondary air control
solenoid valve
Ignition switch: ON System voltage
8 Fuel pump relay Ignition switch: ON System voltage
Engine: Idling 0 – 3 V
10 Power transistor unit
(A)
Engine speed: 3,000 r/min 0.3 – 3.0 V
23 Power transistor unit
(B)
11 Wastegate solenoid
Ignition switch: ON System voltage
va
ve
Engine: At idle after having been warmed up (when
premium gasoline is used)
0 – 3 V
12 Power supply Ignition switch: ON System voltage
25
19 Air flow sensor reset
Engine: Idling 0 – 1 V
s
gna
Engine speed: 3,000 r/min 6 – 9 V
20 Fan motor relay (HI)
<EVOLUTION-IV, V>
Fan not operating (coolant temperature: 90_C or
below)
System voltage
Fan at high speed (coolant temperature: 105_C or
above)
0 – 3 V