
MPI –
Troubleshooting
13-64
Terminal
No.
Normal condition
Check condition (Engine condition)
Check item
20
Radiator fan motor
relay (HI)
<EVOLUTION VI>
Radiator fan not operating (coolant temperature:
95
_
C or below)
System voltage
<EVOLUTION-VI>
Radiator fan at high speed (coolant temperature:
105
_
C or above)
0 – 3 V
21
Fan motor relay (LOW)
<EVOLUTION-IV, V>
Fan not operating (coolant temperature: 95
_
C or
below)
System voltage
Fan at low speed (coolant temperature: 95 – 100
_
C)
0 – 3 V
21
Radiator fan motor
relay (LOW)
<EVOLUTION VI>
Radiator fan not operating (coolant temperature:
95
_
C or below)
System voltage
<EVOLUTION-VI>
Radiator fan at low speed (coolant temperature: 95
– 105
_
C)
0 – 3 V
22
A/C relay
D
Engine: Idling
D
A/C switch: OFF to ON (Compressor is being
driven.)
System voltage, or 6
V or more instanta-
neously to 0 – 3 V
32
A/C condenser fan
motor relay (HI)
<EVOLUTION VI>
A/C condenser fan not operating (A/C switch: ON,
coolant temperature: 105
_
C or below)
System voltage
<EVOLUTION-VI>
A/C condenser fan at high speed (A/C switch: ON,
coolant temperature: 105
_
C or above)
0 – 3 V
33
Alternator G 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 rises by 0.2 –
3.5 V.
34
A/C condenser fan
motor relay (LOW)
<EVOLUTION VI>
A/C condenser fan not operating (A/C switch: OFF,
coolant temperature: 105
_
C or below)
System voltage
<EVOLUTION-VI>
A/C condenser fan at low speed (A/C switch: OFF,
coolant temperature: 105
_
C or above)
0 – 3 V
36
Engine warning lamp
Ignition switch: OFF
→
ON
0 – 3 V
→
System
voltage (After several
seconds have
elapsed)
37
Power steering fluid
pressure switch
Engine: Idling after
warming up
When steering wheel is
stationary
System voltage
When steering wheel is
turned
0 – 3 V
38
Control relay
Ignition switch: OFF
System voltage
Ignition switch: ON
0 – 3 V
39
Fuel pump relay No.2
While engine is idling, suddenly depress the
accelerator pedal.
Momentarily rises
slightly from 0 to 3 V.
40
Exhaust temperature
warning lamp
Ignition switch: OFF to ON
0 – 3 V to system
voltage (After several
seconds have
elapsed)