ignition MITSUBISHI TRITON 1997 Repair Manual

MPI ± Troubleshooting13A-60
Item
No.Reference
page Inspection
procedure
No. Normal condition Inspection contents Inspection
item
28A/C switchEngine: Idling
(when A/C switch isA/C switch: OFFOFFProcedure
No. 2913A-43
(
ON, A/C compressor
should be operating.)A/C switch: ONON
29Inhibitor
switch
Ignition switch: ONP or NP or NProcedure
No 27
13A-42
switch
D, 2, L or RD, 2, L or R
No. 27
41Injectors *3Engine: CrankingWhen engine cool-
ant temperature is
0C51 ± 76 ms
<4G63>
60 ± 90 ms
<4G64>±±
When engine
coolant temperature
is 20C26 ± 38 ms
<4G63>
30 ± 45 ms
<4G64>
When engine
coolant temperature
is 80C5.7 ± 8.5 ms
<4G63>
6.7 ± 10.1 ms
<4G64>
Injectors*4
Engine coolant
temperature:
80 ± 95C

Lamps and all
accessories: OFF
Engine is idling1.9 ± 3.1 ms
<4G63>
2.2 ± 3.4 ms
<4G64>
accessories: OFF

Transmission:
Neutral (A/T :
P range)2,500 r/min1.8 ± 3.0 ms
<4G63>
1.9 ± 3.1 ms
<4G64>
When engine is
suddenly racedIncreases
44Ignition coils
and power
Engine: After
having warmed upEngine is idling2±18BTDC±±
transistors
g

Timing lamp is set.
(The timing lamp
is set in order to
check actual
ignition timing.)2,500 r/min23 ± 43 BTDC
<4G63>
27 ± 47 BTDC
<4G64>

MPI ± Troubleshooting13A-62
ACTUATOR TEST REFERENCE TABLE13100900210
Item
No.Inspection
itemDrive contentsInspection contentsNormal conditionInspection
procedure
No.Reference
page
01InjectorsCut fuel to No.1,
No.3 injectorEngine:
After having warmed up/En-
gine is idling
(Cut the fuel supply to each
Idling condition
becomes different
(becomes unsta-
ble)
Code No.
4113A-19
02Cut fuel to No.2,
No.4 injector(Cut the fuel supply to each
injector in turn and check
cylinders which don't affect
idling.)
ble).
07Fuel pumpFuel pump
operates and
fuel is recircu-
lated.
Engine:
Cranking

Fuel
pump:
Forced
driving
Inspect
accord-
Pinch the
return hose
with fingers
to feel the
pulse of the
fuel being
recirculated.Pulse is felt.Procedure
No. 2413A-40
accord-
ing to
both the
above
condi-
tions.
Listen near
the fuel tank
for the
sound of fuel
pump
operation.Sound of operation
is heard.
08Purge
control
solenoid
valveSolenoid valve
turns from OFF
to ON.Ignition switch: ONSound of operation
can be heard when
solenoid valve is
driven.Procedure
No. 3213A-45
10EGR
control
solenoid
valveSolenoid valve
turns from OFF
to ON.Ignition switch: ONSound of operation
can be heard when
solenoid valve is
driven.Procedure
No. 3313A-46

MPI ± Troubleshooting13A-65
Terminal No.Normal condition Check condition (Engine condition) Check item
35Oxygen sensor heaterEngine: Idling after warming up0±3V
Engine r/min: 5,000r/min.System voltage
36Engine warning lampIgnition switch: OFF
ON0 ± 3V
9 ± 13V
(After several seconds have
elapsed)
37Power steering fluid
pressure switchEngine: Idling after
warming upWhen steering
wheel is stationarySystem voltage
When steering
wheel is turned0±3V
38Control relay
(Power supply)
Ignition switch: OFFSystem voltage
(Power su ly)
Ignition switch: ON0±3V
45A/C switchEngine: Idle speedTurn the A/C
switch OFF0±3V
Turn the A/C
switch ON (A/C
compressor is
operating)System voltage
51Ignition switch ± STEngine: Cranking8V or more
52Intake air temperature
sensorIgnition switch:
ONWhen intake air
temperature is
0
C3.2 ± 3.8V
When intake air
temperature is
20
C2.3 ± 2.9V
When intake air
temperature is
40
C1.5 ± 2.1V
When intake air
temperature is
80
C0.4 ± 1.0V
56Oxygen sensorEngine: Running at 2,500 r/min after
warmed up (Check using a digital type
voltmeter)0
0.8V
(Changes repeatedly)
60Backup power supplyIgnition switch: OFFSystem voltage
61Sensor impressed
voltageIgnition switch: ON4.5 ± 5.5V
62Ignition switch ± IGIgnition switch: ONSystem voltage

MPI ± TroubleshootingMPI ± Troubleshooting13A-66
Terminal No.Normal condition Check condition (Engine condition) Check item
63Engine coolant
temperature sensorIgnition switch:
ONWhen engine
coolant tempera-
ture is 0C3.2 ± 3.8V
When engine
coolant tempera-
ture is 20C2.3 ± 2.9V
When engine
coolant tempera-
ture is 40C1.3 ± 1.9V
When engine
coolant tempera-
ture is 80C0.3 ± 0.9V
64Throttle position
sensorIgnition switch:
ONSet throttle valve
to idle position0.3 ± 1.0V
Fully open throttle
valve4.5 ± 5.5V
65Barometric pressure
sensorIgnition switch:
ONWhen altitude is
0m3.7 ± 4.3V
When altitude is
1,200m3.2 ± 3.8V
66Vehicle speed sensor
Ignition switch: ON

Move the vehicle slowly forward0
5V
(Changes repeatedly)
67Idle position switchIgnition switch:
ONSet throttle valve
to idle position0±1V
Slightly open
throttle valve4V or more
68Top dead centre sensorEngine: Cranking0.4 ± 3.0V
Engine: Idle speed0.5 ± 2.0V
69Crank angle sensorEngine: Cranking0.4 ± 4.0V
Engine: Idle speed1.5 ± 2.5V
70Air flow sensorEngine: Idle speed2.2 ± 3.2V
Engine r/min: 2,500r/min
71Inhibitor switch Ignition switch:
ONSet selector lever
to P or N0±3V
Set selector lever
to Other than P or
N8 ± 14V

ENGINE ELECTRICAL ± Charging System16-6
This test determines whether the alternator output
current is normal.
(1) Before the test, always be sure to check the
following.

Alternator installation

Battery (Refer to GROUP 54 ± Battery.)
NOTE
The battery should be slightly discharged.
The load needed by a fully-charged battery
is insufficient for an accurate test.

Alternator drive belt tension (Refer to
GROUP 11 ± On-vehicle Service.)

Fusible link

Abnormal noise from the alternator while
the engine is running.
(2) Turn the ignition switch off.
(3) Disconnect the negative battery cable.
(4) Disconnect the alternator output wire from the
alternator ªBº terminal. Connect a DC test
ammeter with a range of 0 ± 100 A in series
between the ªBº terminal and the disconnected
output wire. (Connect the (+) lead of the
ammeter to the ªBº terminal. Connect the (±)
lead of the ammeter to the disconnected output
wire.)
Caution
Never use clips but tighten bolts and nuts
to connect the line. Otherwise loose
connections (e.g. using clips) will lead to
a serious accident because of high current.
NOTE
An inductive-type ammeter which enables
measurements to be taken without
disconnecting the alternator output wire should
be recommended.
(5) Connect a voltmeter with a range of 0 ± 20 V
between the alternator ªBº terminal and the
earth. (Connect the (+) lead of the voltmeter
to the ªBº terminal, and then connect the (±)
lead of the voltmeter to the earth.)
(6) Connect the negative battery cable.
(7) Connect a tachometer. (Refer to GROUP 11
± On-vehicle Service.)
(8) Leave the hood open.
(9) Check that the reading on the voltmeter is equal
to the battery voltage.
NOTE
If the voltage is 0 V, the cause is probably
an open circuit in the wire or fusible link between
the alternator ªBº terminal and the battery (+)
terminal.(10)Turn the light switch on to turn on headlamps
and then start the engine.
(11) Immediately after setting the headlamps to high
beam and turning the heater blower switch to
the high revolution position, increase the engine
speed to 2,500 r/min and read the maximum
current output value displayed on the ammeter.
Limit: 70% of normal current output
NOTE

For the nominal current output, refer to the
Alternator Specifications.

Because the current from the battery will
soon drop after the engine is started, the
above step should be carried out as quickly
as possible in order to obtain the maximum
current output value.

The current output value will depend on
the electrical load and the temperature of
the alternator body.

If the electrical load is small while testing,
the specified level of current may not be
output even though the alternator is normal.
In such cases, increase the electrical load
by leaving the headlamps turned on for
some time to discharge the battery or by
using the lighting system in another vehicle,
and then test again.

The specified level of current also may not
be output if the temperature of the alternator
body or the ambient temperature is too
high. In such cases, cool the alternator and
then test again.
(12)The reading on the ammeter should be above
the limit value. If the reading is below the limit
value and the alternator output wire is normal,
remove the alternator from the engine and
check the alternator.
(13)Run the engine at idle after the test.
(14)Turn the ignition switch off.
(15)Remove the tachometer.
(16)Disconnect the negative battery cable.
(17)Disconnect the ammeter and voltmeter.
(18)Connect the alternator output wire to the
alternator ªBº terminal.
(19)Connect the negative battery cable.

ENGINE ELECTRICAL ± Charging System16-8
(14)If the voltage reading conforms to the value
in the voltage regulation, then the voltage
regulator is operating normally.
If the voltage is not within the standard value,
there is a malfunction of the voltage regulator
or of the alternator.
(15)After the test, lower the engine speed to the
idle speed.
(16)Turn the ignition switch off.(17)Remove the tachometer.
(18)Disconnect the negative battery cable.
(19)Disconnect the ammeter and voltmeter.
(20)Connect the alternator output wire to the
alternator ªBº terminal.
(21)Remove the special tool, and return the
connector to the original condition.
(22)Connect the negative battery cable.
Voltage Regulation Table
Standard value:
Inspection terminalVoltage regulator ambient temperature
CVoltage V
Terminal ªSº±2014.2 ± 15.4
2013.9 ± 14.9
6013.4 ± 14.6
8013.1 ± 14.5

ENGINE ELECTRICAL ± Ignition System16-34
WAVEFORM OBSERVATION POINTS
Point A: The height, length and slope of the spark line show the following trends (Refer to abnormal
waveform examples, 1, 2, 3 and 4).
Spark linePlug gapCondition of
electrodeCompression
forceConcentration of
air mixtureIgnition timingSpark plug
cable
LengthLongSmallNormalLowRichAdvancedLeak
ShortLargeLarge wearHighLeanRetardedHigh
resistance
HeightHighLargeLarge wearHighLeanRetardedHigh
resistance
LowSmallNormalLowRichAdvancedLeak
SlopeLargePlug is fouled±±±±
Point B: Number of vibration in reduction vibration section (Refer to abnormal waveform example 5)
Number of vibrationsCoil and condenser
Three or moreNormal
Except aboveAbnormal
Point C: Number of vibrations at beginning of dwell section (Refer to abnormal waveform example 5)
Number of vibrationsCoil
5 ± 6 or higherNormal
Except aboveAbnormal
Point D: Ignition voltage height (distribution per each cylinder) shows the following trends.
Ignition
voltagePlug gapCondition of
electrodeCompression
forceConcentration of
air mixtureIgnition timingSpark plug cable
HighLargeLarge wearHighLeanRetardedHigh resistance
LowSmallNormalLowRichAdvancedLeak

ENGINE ELECTRICAL ± Ignition System16-38
WAVEFORM OBSERVATION POINTS
Point A: The height, length and slope of the spark line (refer to abnormal waveform examples 1, 2,
3 and 4) show the following trends.
Spark linePlug gapCondition of
electrodeCompression
forceConcentration of
air mixtureIgnition timingHigh tension
cable
LengthLongSmallNormalLowRichAdvancedLeak
ShortLargeLarge wearHighLeanRetardedHigh
resistance
HeightHighLargeLarge wearHighLeanRetardedHigh
resistance
LowSmallNormalLowRichAdvancedLeak
SlopeLargePlug is fouled±±±±
Point B: Number of vibration in reduction vibration section
(Refer to abnormal waveform example 5)
Number of vibrationsCoil, condenser
3 or higherNormal
Except aboveAbnormal
Point C: Height of Zener voltage
Height of Zener voltageProbable cause
HighProblem in Zener diode
LowAbnormal resistance in
primary coil circuit

MANUAL TRANSMISSION ± 4WD Indicator-ECU22-16
Terminal No.Inspection itemInspection condition
1: Ignition switchInspection condition
2: Transfer lever positionTerminal voltage
1Free wheel engage
switch
ON2HSystem voltage
switch
4H*10 V
24WD detection
switch
ON2HSystem voltage
switch
4H, 4L0 V
3Ignition switch (IG1)OFF±0 V
ON±System voltage
5Free wheel differen-
tial indicator lamp
ON2HSystem voltage
tial indicator lam
4H*10 V
6HI/LOW detection
switchONShifting from 4H to 4L
or vice versaSystem voltage
2H, 4H, 4L0 V
7Free wheel clutch
changeover solenoid
ON4H, 4L0 V
changeover solenoid
valve2H*2System voltage
104WD Indicator lampON2H0 V
4H, 4LSystem voltage
NOTE
*1: When vehicle has been moved once.
*2: Shift the lever from 4H to 2H, and then turn the ignition switch to OFF and then back to ON.

ABS <2WD> ± Troubleshooting35B-11
Code No. 51 Valve relayProbable cause
When the ignition switch is turned to ON, the ABS-ECU switches the valve relay
off and on during the initial check. In that way, the ABS-ECU compares the signals
sent to the valve relay with the voltage in the valve power monitor line. That is how
to check if the valve relay is operating normally. The ABS-ECU always checks if
current flows in the valve power monitor line, too. It determines that there is an open
circuit when no current flows. If no current flows in the valve power monitor line,
this diagnosis code is output.
Malfunction of valve relay

Malfunction of wiring harness or connector

Malfunction of ABS-ECU

Malfunction of hydraulic unit
NOTE
Whenever reading the diagnosis codes using the ABS warning lamp (Refer to GROUP 00 ± How to
Use Troubleshooting/Inspection Service Points), this diagnosis code will be output. That is not a malfunction
but because the valve relay connector is disconnected. After repairing all other malfunctions, connect
the valve relay connector again to check the valve relay. Then check that the ABS warning lamp does
not illuminate. If it illuminates, the valve relay may be defective. So carry out the following procedure.
Valve relay check. (Refer to P. 35B-28.)NGReplace the valve relay.
OK
Measure at valve relay connector A-39.

Disconnect the connector and
measure at the harness side.

Voltage between 6 ± body earth
OK:System voltageNGCheck the harness between fusible link
No. 11 and valve relay, and repair if nec-
essary.
OK
Measure at ABS-ECU connector C-62
and C-64.

Disconnect the connector and
measure at the harness side.

Resistance between 26 ± 37
OK:60 ± 120 WNGCheck the following connector.
A-39OKCheck trouble symptoms.
NG
Check the harness between valve relay
and ABS-ECU, and repair if necessary.
OK
Measure at ABS-ECU connector C-64.

Disconnect the connector and
measure at the harness side.

Continuity between 48 ± body earth
OK:ContinuityNGCheck the harness between the valve
relay and ABS-ECU, and repair if neces-
sary.
OK
Check the following connector.
C-64OKCheck trouble symptoms.NGReplace the ABS-ECU.