1999 MITSUBISHI LANCER EVOLUTION VI radiator

MPI – Troubleshooting13-7
FAIL-SAFE FUNCTION REFERENCE TABLE
When the main sensor malfunctions are detected by the diagnosis function, the vehicle is controlled
by means of the pre-set control logic to maintain safe conditions for driving.
Malfunctioning itemControl contents during malfunction
Air flow sensor1. Uses the throttle position sensor signal and engine speed signal (crank angle sensor
signal) to take reading of the basic injector drive time and basic ignition timing from
the pre-set mapping.
2. Fixes the ISC servo in the appointed position so idle control is not performed.
Intake air temperature
sensorControls as if the intake air temperature is 25C.
Throttle position
sensorNo increase in fuel injection amount during acceleration due to the throttle position sensor
signal.
Engine coolant
temperature sensor1. Controls as if the engine coolant temperature is 80C.
(This condition is maintained until the ignition switch is turned off even when the
sensor signal returns normal.)
2. Lets the fan motor (radiator and condenser) run at high speed.
Camshaft position
sensorInjects fuel to all cylinders simultaneously for 4 seconds.
(However, after the ignition switch is turned to ON, the No. 1 cylinder top dead centre is not
detected at all.)
Barometric pressure
sensorControls as if the barometric pressure is 101 kPa.
Detonation sensorSwitches the ignition timing from ignition timing for super petrol to ignition timing for standard
petrol.
Ignition coil, power
transistor unitCuts off the fuel supply to cylinders with an abnormal ignition.
Alternator FR terminalDoes not control the output of the alternator according to an electrical load. (works as a
normal alternator)

MPI – Troubleshooting13-17
Code No. 64 Alternator FR terminal systemProbable cause
Range of Check

Engine speed is approx. 50 r/min or more
Set Conditions

The input voltage from the alternator FR terminal is higher than 4.5 V for 20 seconds.
Open circuit in alternator FR terminal circuit

Malfunction of the engine-ECU
Measure at the alternator connector A-05.

Connect the connector. (Use the test harness: MB991519.)

Voltage between 4 (blue clip) and earth
(Engine: Idling)
(Radiator fan: Stopped)
(Headlamp: OFF → ON)
(Brake lamp: OFF → ON)
(Rear window defogger switch: OFF → ON)
OK:Voltage drops 0.2 to 3.5 VOKReplace the engine-ECU.
NG
Measure at the alternator connector A-05.

Disconnect the connector, and measure at the harness side.

Voltage between 4 and earth
(Ignition switch: ON)
OK:4.8 – 5.2 VNGCheck the following
connectors: B-60, A-88NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire
between the engine-ECU
and the alternator con-
nector.NG
Repair
OK
Replace the engine-ECU.
OK
Check the following connector: A-05NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between the engine-ECU and the alternator
connector.NG
Repair
OK
Replace the alternator.

MPI – Troubleshooting13-35
INSPECTION PROCEDURE 23
Low alternator output voltage (approx. 12.3 V)
Probable cause
The alternator may be defective, or malfunctions, which are listed in the right column,
may be suspected.
Malfunction of charging system

Short circuit in harness between alternator G terminal
and engine-ECU

Malfunction of engine-ECU
Measure at the alternator connector
side. A-05

Connect the connector.
(Test harness: MB991519)

Voltage between 1 (black clip) and
earth
Engine: at idle
Radiator fan: does not run
Headlamp: OFF → ON
Brake lamp: OFF → ON
Rear defogger switch:
OFF → ON
OK:Voltages rises
by 0.2 – 3.5 V.NGMeasure at the alternator connector.
A-05

Disconnect the connector, and
measure at the harness side.

Disconnect the engine-ECU con-
nector.

Continuity between 1 and earth
OK:No continuityNGCheck the harness wire between the
alternator and the engine-ECU connec-
tor, and repair if necessary.
OK
Check the alternator.
OK
Check the harness wire between the
alternator and the engine-ECU connec-
tor.NG
Repair
OK
Replace the engine-ECU.
INSPECTION PROCEDURE 24
Power supply system and ignition switch-IG system
Probable cause
When an ignition switch ON signal is input to the engine-ECU, the engine-ECU turns
the control relay ON. This causes system voltage to be supplied to the engine-ECU,
injectors and air flow sensor.
Malfunction of the ignition switch

Malfunction of the control relay

Improper connector contact, open or short-circuited
harness wire

Disconnected engine-ECU earth wire

Malfunction of the engine-ECU
Check the control relay. (Refer to P.13-68.)NG
Replace
OK
Measure at the control relay connector B-27.

Disconnect the connector, and measure at the harness side.

Voltage between 3, 4 and earth
OK:System voltageNGCheck the following
connector: A-28NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between battery and control relay connector,
and repair if necessary.
OK
Check the engine-ECU power supply and earth circuit.
(Refer to P.13-53, INSPECTION PROCEDURE 45.)

MPI – Troubleshooting13-40
INSPECTION PROCEDURE 30
Fan motor relay system (Radiator fan, A/C condenser fan)
Probable cause
The engine-ECU turns on/off the built-in power transistor to control the fan motor
relay.
Malfunction of the fan motor relay

Malfunction of the fan motor

Improper connector contact, open or short-circuited
harness wire

Malfunction of engine-ECU
NG

Check the radiator fan circuit.

Check the A/C condenser fan circuit.
(Refer to Electrical Wirings.)
NG
Replace the engine-ECU.
OK
Check trouble symptom.
Measure at the engine-ECU connector B-59.

Disconnect the connector, and measure at the harness side.

Voltage between each of 20 and 21 and earth
(Ignition switch: ON)
OK:System voltage

Short the terminal 21 to earth.
(Ignition switch: ON)
OK:Fan operates at low speed.

Short the terminals 20 and 21 to earth.
(Ignition switch: ON)
OK:Fan operates at high speed.OKCheck the following connector: B-59NG
Repair

MPI – Troubleshooting13-41
INSPECTION PROCEDURE 30
Fan motor relay system (Radiator fan, A/C condenser fan)
Probable cause
The engine-ECU turns on/off the built-in power transistor to control the fan motor
relay.
Malfunction of the fan motor relay

Malfunction of the fan motor

Malfunction of thermostat

Improper connector contact, open or short-circuited
harness wire

Malfunction of engine-ECU
NG
Check the engine coolant temperature sensor. (Refer to P.13-10,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE 21.)
OK
Replace the engine-ECU.
NG
MUT-II Data list
21 Engine coolant temperature sensor
OK:The engine coolant temperature agrees with the reading
of MUT-II when measured with the engine idling in warm
condition.OKCheck the thermostat.NG
Replace
OK
Check trouble symptom.
OK
Check the following connector: B-60NG
Repair NG
Check the A/C condenser fan circuit. (Refer to Electrical Wirings.)
NG
Measure at the engine-ECU connector B-60.

Disconnect the connector, and measure at the harness side.

Check the A/C condenser fan for operating condition.
(Ignition switch: ON)
OK:A/C condenser fan is stationary.

Voltage between each of 32 and 34 and earth
(Ignition switch: ON)
OK:System voltage

Short the terminal 32 to earth. (Ignition switch: ON)
OK:A/C condenser fan operates at high speed.

Short the terminal 34 to earth. (Ignition switch: ON)
OK:A/C condenser fan operates at low speed.
Check trouble symptom.
OK
OK
Check the following connector: B-59NG
Repair
Measure at the engine-ECU connector B-59.

Disconnect the connector, and measure at the harness side.

Check the radiator fan for operating condition.
(Ignition switch: ON)
OK:Radiator fan is stationary.

Voltage between each of 20 and 21 and earth
(Ignition switch: ON)
OK:System voltage

Short the terminal 20 to earth.
(Ignition switch: ON)
OK:Radiator fan operates at high speed.

Short the terminal 21 to earth.
(Ignition switch: ON)
OK:Radiator fan operates at low speed.NGCheck the radiator fan circuit. (Refer to Electrical Wirings.)

MPI – Troubleshooting13-62
Item
No.Reference
page Inspection
procedure
No. Normal condition Inspection contents Drive contents Inspection
item
20Radiator
fan
(HIGH),
condenser
fan
(HIGH)*
1
Drive the fan
motors (for
radiator and
condenser*
1)

Ignition switch: ON

A/C switch: ON*1Fan motors
operate at high
speed.Procedure
No. 3013-40
21Radiator
fan
(LOW),
condenser
fan
(LOW)*
1
Drive the fan
motors (for
radiator and
condenser*
1)

Ignition switch: ON

A/C switch: ON*1Fan motors
operate at low
speed.
36*2Secondary
air control
solenoid
valveTurn solenoid
valve from
OFF to ON.Ignition switch: ONSound of opera-
tion can be heard
when solenoid
valve is driven.Procedure
No. 3613-46
37*2A/C con-
denser fan
(HIGH)Drive A/C
condenser fan
motorIgnition switch: ONA/C condenser
fan motor oper-
ates at high
speed.Procedure
No. 3013-41
38*2A/C con-
denser fan
(LOW)Drive A/C
condenser fan
motorIgnition switch: ONA/C condenser
fan motor oper-
ates at low speed.
NOTE
*1: EVOLUTION-IV and EVOLUTION-V
*2: EVOLUTION-VI

MPI – Troubleshooting13-64
Terminal
No.Normal condition Check condition (Engine condition) Check item
20Radiator fan motor
relay (HI)

Radiator fan not operating (coolant temperature:
95C or below)System voltage
Radiator fan at high speed (coolant temperature:
105C or above)0 – 3 V
21Fan motor relay (LOW)
Fan not operating (coolant temperature: 95C or
below)System voltage
Fan at low speed (coolant temperature: 95 – 100C)0 – 3 V
21Radiator fan motor
relay (LOW)

Radiator fan not operating (coolant temperature:
95C or below)System voltage
Radiator fan at low speed (coolant temperature: 95
– 105C)0 – 3 V
22A/C relay
Engine: Idling

A/C switch: OFF to ON (Compressor is being
driven.)System voltage, or 6
V or more instanta-
neously to 0 – 3 V
32A/C condenser fan
motor relay (HI)

A/C condenser fan not operating (A/C switch: ON,
coolant temperature: 105C or below)System voltage
A/C condenser fan at high speed (A/C switch: ON,
coolant temperature: 105C or above)0 – 3 V
33Alternator G terminal
Engine: Warm, idle (radiator fan: OFF)

Headlamp: OFF to ON

Brake lamp: OFF to ON

Rear defogger switch: OFF to ONVoltage rises by 0.2 –
3.5 V.
34A/C condenser fan
motor relay (LOW)

A/C condenser fan not operating (A/C switch: OFF,
coolant temperature: 105C or below)System voltage
A/C condenser fan at low speed (A/C switch: OFF,
coolant temperature: 105C or above)0 – 3 V
36Engine warning lampIgnition switch: OFF → ON0 – 3 V → System
voltage (After several
seconds have
elapsed)
37Power steering fluid
pressure switchEngine: Idling after
warming upWhen steering wheel is
stationarySystem voltage
When steering wheel is
turned0 – 3 V
38Control relayIgnition switch: OFFSystem voltage
Ignition switch: ON0 – 3 V
39Fuel pump relay No.2While engine is idling, suddenly depress the
accelerator pedal.Momentarily rises
slightly from 0 to 3 V.
40Exhaust temperature
warning lampIgnition switch: OFF to ON0 – 3 V to system
voltage (After several
seconds have
elapsed)

MPI – Troubleshooting13-65
Terminal
No.Normal condition Check condition (Engine condition) Check item
41Alternator FR terminal
Engine: Warm, idle (radiator fan: OFF)

Headlamp: OFF to ON

Brake lamp: OFF to ON

Rear defogger switch: OFF to ONVoltage drops by 0.2 –
3.5 V.
45A/C switchEngine: Idle speedTurn the A/C switch OFF0 – 3 V
Turn the A/C switch ON
(A/C compressor is oper-
ating)System voltage
60Oxygen sensor heater

Engine: Idling0 – 3 V

Engine speed: 5,000 r/minSystem voltage
71Ignition switch-STEngine: Cranking8 V or more
72Intake air temperature
sensorIgnition switch: ONWhen intake air tempera-
ture is 0C3.2 – 3.8 V
When intake air tempera-
ture is 20C2.3 – 2.9 V
When intake air tempera-
ture is 40C1.5 – 2.1 V
When intake air tempera-
ture is 80C0.4 – 1.0 V
76Oxygen sensorEngine: Running at 2,000 r/min after having been
warmed up (Check using a digital type voltmeter)0 ↔ 0.8 V
(Changes repeatedly)
80Backup power supplyIgnition switch: OFFSystem voltage
81Sensor impressed
voltageIgnition switch: ON4.5 – 5.5 V
82Ignition switch-IGIgnition switch: ONSystem voltage
83Engine coolant
temperature sensorIgnition switch: ONWhen engine coolant
temperature is 0C3.2 – 3.8 V
When engine coolant
temperature is 20C2.3 – 2.9 V
When engine coolant
temperature is 40C1.3 – 1.9 V
When engine coolant
temperature is 80C0.3 – 0.9 V
84Throttle position sensorIgnition switch: ONSet throttle valve to idle
position0.3 – 1.0 V
Fully open throttle valve4.5 – 5.5 V
85Barometric pressure
sensor
Ignition switch: ONWhen altitude is 0 m3.7 – 4.3 V
sensor
When altitude is 1,200 m3.2 – 3.8 V
86Vehicle speed sensor
Ignition switch: ON

Move the vehicle slowly forward0 ↔ 5 V
(Changes repeatedly)