
MPI –
Troubleshooting
13-65
Terminal
No.
Normal condition
Check condition (Engine condition)
Check item
41
Alternator FR terminal
D
Engine: Warm, idle (radiator fan: OFF)
D
Headlamp: OFF to ON
D
Brake lamp: OFF to ON
D
Rear defogger switch: OFF to ON
Voltage drops by 0.2 –
3.5 V.
45
A/C switch
Engine: Idle speed
Turn the A/C switch OFF
0 – 3 V
Turn the A/C switch ON
(A/C compressor is oper-
ating)
System voltage
60
Oxygen sensor heater
<EVOLUTION V VI>
Engine: Idling
0 – 3 V
<EVOLUTION-V, VI>
Engine speed: 5,000 r/min
System voltage
71
Ignition switch-ST
Engine: Cranking
8 V or more
72
Intake air temperature
sensor
Ignition switch: ON
When intake air tempera-
ture is 0
_
C
3.2 – 3.8 V
When intake air tempera-
ture is 20
_
C
2.3 – 2.9 V
When intake air tempera-
ture is 40
_
C
1.5 – 2.1 V
When intake air tempera-
ture is 80
_
C
0.4 – 1.0 V
76
Oxygen sensor
Engine: Running at 2,000 r/min after having been
warmed up (Check using a digital type voltmeter)
0
↔
0.8 V
(Changes repeatedly)
80
Backup power supply
Ignition switch: OFF
System voltage
81
Sensor impressed
voltage
Ignition switch: ON
4.5 – 5.5 V
82
Ignition switch-IG
Ignition switch: ON
System voltage
83
Engine coolant
temperature sensor
Ignition switch: ON
When engine coolant
temperature is 0
_
C
3.2 – 3.8 V
When engine coolant
temperature is 20
_
C
2.3 – 2.9 V
When engine coolant
temperature is 40
_
C
1.3 – 1.9 V
When engine coolant
temperature is 80
_
C
0.3 – 0.9 V
84
Throttle position sensor
Ignition switch: ON
Set throttle valve to idle
position
0.3 – 1.0 V
Fully open throttle valve
4.5 – 5.5 V
85
Barometric pressure
sensor
Ignition switch: ON
When altitude is 0 m
3.7 – 4.3 V
sensor
When altitude is 1,200 m
3.2 – 3.8 V
86
Vehicle speed sensor
D
Ignition switch: ON
D
Move the vehicle slowly forward
0
↔
5 V
(Changes repeatedly)