1999 MITSUBISHI LANCER EVOLUTION VI display
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GENERAL – How to Use Troubleshooting/Inspection Service Points00-6
HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE
POINTS
Troubleshooting of electronic control systems for which the MUT-II can be used follows the basic outline
described below. Furthermore, even in systems for which the MUT-II cannot be used, part of these systems
still follow this outline.
TROUBLESHOOTING CONTENTS
1. STANDARD FLOW OF DIAGNOSIS TROUBLESHOOTING
The troubleshooting sections follow the basic diagnosis flow which is given below. If the diagnosis
flow is different from that given below, or if additional explanation is required, the details of such
differences or additions will also be listed.
Diagnosis method
Gathering information
from the customer.
Check trouble symptom.
Reoccurs Does not reoccur.
Read the diagnosis code
No diagnosis code
or communication
with MUT-II not
possible
Refer to the INSPECTION
CHART FOR TROUBLE
SYMPTOMS (Refer to
applicable group.)Diagnosis code
displayed.
Read the diagnosis code
Diagnosis code
displayed.No diagnosis
code
After taking note of the
malfunction code, erase
the diagnosis code
memory
Recheck trouble symptom.
Diagnosis code
displayed.
Read the diagnosis codes.
No diagnosis
code
Refer to the INSPECTION CHART FOR DIAGNOSIS
CODES (Refer to applicable group.)INTERMITTENT MALFUNCTIONS (Refer to P.00-13.)
2. SYSTEM OPERATION AND SYMPTOM VERIFICATION TESTS
If verification of the trouble symptoms is difficult, procedures for checking operation and verifying
trouble symptoms are shown.
3. DIAGNOSIS FUNCTION
Details which are different from those in the “Diagnosis Function” section on the next page are listed.
Page 12 of 558
GENERAL – How to Use Troubleshooting/Inspection Service Points00-9
Diagnosis result display method when using a voltmeter
Example of diagnosis code voltage wave pattern for
diagnosis code No. 24Normal voltage wave pattern
12V
0 V
1.5 secs.0.5 sec.0.5 sec.
Pause
time 3
secs.Tens
signalPlace
division
2 secs.Units
signal
12 V
0 V
0.5 sec.
METHOD OF ERASING DIAGNOSIS CODES
WHEN USING THE MUT-II
Connect the MUT-II to the diagnosis connector and erase the diagnosis code.
Caution
Turn off the ignition switch before connecting or disconnecting the MUT-II.
WHEN NOT USING THE MUT-II
(1) Turn the ignition switch to OFF.
(2) After disconnecting the battery cable from the battery (–) terminal for 10 seconds or more, reconnect
the cable.
(3) After the engine has warmed up, run it at idle for about 15 minutes.
INPUT SIGNAL INSPECTION POINTS
WHEN USING THE MUT-II
1. Connect the MUT-II to the diagnosis connector.
Caution
The MUT-II should be connected or disconnected after
turning the ignition switch to the OFF position.
2. If buzzer of the MUT-II sounds once when the each switch
is operated (ON/OFF), the ETACS-ECU input signal for
that switch circuit system is normal.
WHEN USING VOLTMETER
1. Use the special tool to connect a voltmeter between
the earth terminal (No. 4 or 5) and the ETACS terminal
(No. 9) of the diagnosis connector.
2. If the voltmeter indicator deflects once when the each
switch is operated (ON/OFF), the ETACS-ECU input signal
for that switch circuit system is normal.
MUT-II
Earth terminal
ETACS terminal
MB991529
Page 133 of 558
MPI – Troubleshooting13-21
INSPECTION PROCEDURE 3
The engine warning lamp does not illuminate right after
the ignition switch is turned to the ON position.
Probable cause
For checking for burnt-out bulb, the engine-ECU causes the engine warning lamp
to illuminate for five seconds immediately after the ignition switch is turned to ON.
If the engine warning lamp does not illuminate immediately after the ignition switch
is turned to ON, one of the malfunctions listed at right has probably occurred.Burnt-out bulb of the engine warning lamp
Defective engine warning lamp circuit
Malfunction of the engine-ECU
MUT-II Data list
16 engine-ECU power supply voltage (Refer to P.13-57)NGCheck the engine-ECU power supply and earth circuit.
(Refer to P.13-53, INSPECTION PROCEDURE 45.)
OK
Measure at the engine-ECU connector B-60.
Disconnect the connector, and measure at the harness side.
Earth the terminal No.36. (Ignition switch: ON)
OK:The engine warning lamp illuminates.OKCheck the following
connector: B-60NG
Repair
OK
Check trouble symptom.
NG
Replace the engine-ECU.
NG
Check for burnt-out bulb.NG
Replace
OK
Measure at the combination meter connector B-08.
Disconnect the connector, and measure at the harness side.
Voltage between 42 and earth (Ignition switch: ON)
OK:System voltageNGCheck the engine warning lamp power supply circuit, and repair
if necessary.
OK
Check the following connectors:
B-08, B-65, B-60NG
Repair
OK
Check trouble symptom.NGCheck the harness wire between combination meter and engine-
ECU connector, and repair if necessary.
INSPECTION PROCEDURE 4
The engine warning lamp remains illuminating and never
goes out.
Probable cause
In cases such as the above, the cause is probably that the engine-ECU is detecting
a problem in a sensor or actuator, or that one of the malfunctions listed at right has
occurred.Short-circuit between the engine warning lamp and
engine-ECU
Malfunction of the engine-ECU
MUT-II Self-Diag code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
No
Measure at the combination meter connector B-08.
Disconnect the connector, and measure at the harness side.
Disconnect the engine-ECU connector
Continuity between 53 and earth
OK:No continuityNGCheck the harness wire between combination meter and engine-
ECU connector, and repair if necessary.
OK
Replace the engine-ECU.
Page 137 of 558
MPI – Troubleshooting13-25
INSPECTION PROCEDURE 8
Unstable idling (Rough idling, hunting)
Probable cause
In cases as the above, the cause is probably that the ignition system, air/fuel mixture,
idle speed control (ISC) or compression pressure is defective.
Because the range of possible causes is broad, inspection is narrowed down to simple
items.Malfunction of the ignition system
Malfunction of air-fuel ratio control system
Malfunction of the ISC servo system
Poor compression
Drawing air into exhaust system
Secondary air backflow to the intake system
Were the battery terminals disconnected recently?Ye sAfter warming-up, let the engine run at idling for about 10 minutes.
No
MUT-II Self-Diag code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
No
Does idling speed fluctuate excessively?Ye sCheck if hunting occurs.
(Refer to P.13-48, INSPECTION PROCEDURE 40.)
No
Check the ISC servo for operation sound.NGCheck the ISC servo system.
(Refer to P.13-44, INSPECTION PROCEDURE 33.)
OK
Check the injector for operation.NGCheck the injector system. (Refer to P.13-15, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE 41.)
OK
MUT-II: Check if idling speed is unstable.
(Refer to P.13-49, INSPECTION PROCEDURE 41.)
OK
Check the ignition timing.
(Refer to GROUP 11 – Engine Adjustment.)*NGCheck that the crank angle sensor and the timing belt cover are
installed properly.
OK
Check the following items.
Check the ignition coil, spark plugs, spark plug cables.
Check the secondary air supply system. (Ensure that there is no back flow of secondary air into the intake system.)
Check the compression pressure.
Check if foreign materials (water, alcohol, etc.) got into fuel.
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).
Page 138 of 558
MPI – Troubleshooting13-26
INSPECTION PROCEDURE 9
Idling speed is high. (Improper idling speed)
Probable cause
In such cases as the above, the cause is probably that the intake air volume during
idling is too great.Malfunction of the ISC servo system
Malfunction of the throttle body
OK
MUT-II Data list
26 Idle position switch (Refer to P.13-58.)NGCheck the idle position switch system.
(Refer to P.13-38, INSPECTION PROCEDURE 26.)
No
Check the ISC servo for operation sound.NGCheck the ISC servo system.
(Refer to P.13-44, INSPECTION PROCEDURE 33.)
OK
MUT-II Data list
21 Engine coolant temperature sensor (Refer to P.13-57.)NGCheck the engine coolant temperature sensor system.
(Refer to P.13-10, INSPECTION PROCEDURE FOR DIAGNOSIS
CODE 21.)
OK
MUT-II Data list
28 A/C switch (Refer to P.13-58.)NGCheck the A/C switch and A/C relay system.
(Refer to P.13-39, INSPECTION PROCEDURE 29.)
OK
Basic idle speed adjustment (Refer to P.13-30.)*
Check trouble symptom.NGClean the throttle valve area.
Adjust the fixed SAS. (Refer to P.13-30.)*
MUT-II Self-Diag code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).
Page 139 of 558
MPI – Troubleshooting13-27
INSPECTION PROCEDURE 10
Idling speed is low. (Improper idling speed)
Probable cause
In cases such as the above, the cause is probably that the intake air volume during
idling is too small.Malfunction of the ISC servo system
Malfunction of the throttle body
MUT-II Self-Diag code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
No
Check the ISC servo for operation sound.NGCheck the ISC servo system.
(Refer to P.13-44, INSPECTION PROCEDURE 33.)
OK
MUT-II Data list
26 Idle position switch (Refer to P.13-58.)NGCheck the idle position switch system.
(Refer to P.13-38, INSPECTION PROCEDURE 26.)
OK
MUT-II Data list
21 Engine coolant temperature sensor (Refer to P.13-57.)NGCheck the engine coolant temperature sensor system.
(Refer to P.13-10, INSPECTION PROCEDURE FOR DIAGNOSIS
CODE 21.)
OK
Basic idle speed adjustment (Refer to P.13-30.)*
Check trouble symptom.NGClean the throttle valve area.
Adjust the fixed SAS. (Refer to P.13-30.)*
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).
Page 140 of 558
MPI – Troubleshooting13-28
INSPECTION PROCEDURE 11
When the engine is cold, it stalls at idling. (Die out)
Probable cause
In such cases as the above, the cause is probably that the air/fuel mixture is inappropriate
when the engine is cold, or that the intake air volume is insufficient.Malfunction of the ISC servo system
Malfunction of the throttle body
Malfunction of the injector system
Malfunction of the ignition system
Were the battery terminals disconnected recently?Ye sAfter warming-up, let the engine run at idling for about 10 minutes.
No
MUT-II Self-Diag code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
OK
Check the fuel pressure. (Refer to P.13-30.)*
OK
Check the ignition timing.
(Refer to GROUP 11 – Engine Adjustments.)*NGCheck that the crank angle sensor and the timing belt cover are
installed properly.
OK
Check the following items.
Check the ignition coil, spark plugs, spark plug cables.
Check the compression pressure.
Check the engine oil viscosity.
OK
MUT-II Data list
26 Idle position switch (Refer to P.13-58.)NGCheck the idle position switch system.
(Refer to P.13-38, INSPECTION PROCEDURE 26.)
OK
Check the injector for operation sound.NGCheck the injector system. (Refer to P.13-15, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE 41.)
Ye s
Check the ISC servo for operation sound.NGCheck the ISC servo system.
(Refer to P.13-44, INSPECTION PROCEDURE 33.)
No
Is engine-idling stable after the warming-up?NoCheck for unstable idling (Rough idling, hunting).
(Refer to P.13-25, INSPECTION PROCEDURE 8.)
No
Does the engine stall right after the accelerator pedal is released?Ye sClean the throttle valve
area.Adjust the fixed SAS.
(Refer to P.13-30.)*
OK
MUT-II Data list
21 Engine coolant temperature sensor (Refer to P.13-57.)NGCheck the engine coolant temperature sensor system.
(Refer to P.13-10, INSPECTION PROCEDURE FOR DIAGNOSIS
CODE 21.)
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).
Page 141 of 558
MPI – Troubleshooting13-29
INSPECTION PROCEDURE 12
When the engine is hot, it stalls at idling. (Die out)
Probable cause
In such cases as the above, the cause is probably that ignition system, air/fuel mixture,
idle speed control (ISC) or compression pressure is defective.
In addition, if the engine suddenly stalls, the cause may also be a defective connector
contact.Malfunction of the ignition system
Malfunction of air-fuel ratio control system
Malfunction of the ISC servo system
Drawing air into intake system
Improper connector contact
Backflow of secondary air to the intake system
Were the battery terminals disconnected recently?Ye sAfter warming-up, let the engine run at idling for about 10 minutes.
No
MUT-II Diagnosis code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
No
Check the ISC servo for operation sound.NGCheck the ISC servo system.
(Refer to P.13-44, INSPECTION PROCEDURE 33.)
OK
Check the injector for operation sound.NGCheck the injector system. (Refer to P.13-15, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE 41.)
OK
Does the engine stall right after the accelerator pedal is released?Ye sClean the throttle valve
area.Adjust the fixed SAS.
(Refer to P.13-30.)*
No
Does the engine stall easily again?NoWhile carrying out an intermittent malfunction simulation test (Refer
to GROUP 00 – Points to Note for Intermittent Malfunctions.), check
for sudden changes in the signals shown below.
Crank angle sensor signal
Injector drive signal
Fuel pump drive signal
Air flow sensor signalSecondary ignition signal
Engine-ECU power supply
voltage
Ye s
MUT-II: Engine stalling inspection when the engine is warm and
idling. (Refer to P.13-50, INSPECTION PROCEDURE 42.)
OK
Check the ignition timing.
(Refer to GROUP 11 – ENGINE ADJUSTMENTS.)*NGCheck that the crank angle sensor and the timing belt cover are
installed properly.
OK
Check the following items.
Check the ignition coil, spark plugs, spark plug cables.
Check the secondary air supply system. (Ensure that there is no backflow of secondary air into the intake system.)
Check if the injectors are clogged.
Check the compression pressure.
Check if foreign materials (water, alcohol, etc.) got into fuel.
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).