engine MITSUBISHI MONTERO 1998 Service Manual
[x] Cancel search | Manufacturer: MITSUBISHI, Model Year: 1998, Model line: MONTERO, Model: MITSUBISHI MONTERO 1998Pages: 1501, PDF Size: 25.81 MB
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Application Wire Color Location
Diamante .................. Black/Blue ............ (1)
Eclipse (Turbo & 2.4L) .... Black/Blue ............. ( 2)
Galant .................... Black/Blue ............ ( 3)
Mirage .................... Black/Blue ............ ( 1)
Montero ...................... White .............. ( 4)
3000GT .................... Black/Blue ............ ( 6)
( 1) - On firewall, above brake master cylinder.
( 2) - On firewall behind battery.
( 3) - On main wiring harness, near center of firewall.
( 4) - On main wiring harness, near right center of firewall.
( 5) - Near left rear corner of engine compartment, below
cruise control actuator (if equipped).
( 6) - On main wiring harness, near wiper motor on firewall,
behind battery.
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3) Start engine and allow it to idle. Measure fuel pressure
with vacuum hose connected to fuel pressure regulator. Record fuel
pressure reading. See FUEL PUMP PERFORMANCE table. Disconnect and plug
vacuum hose from fuel pressure regulator. Record fuel pressure
reading.
4) Check for fuel pressure in fuel return hose by gently
pinching hose while increasing engine speed. If fuel volume is low,
fuel pressure in return hose will not be felt. Increase engine speed
to 2500-3000 RPM, 2-3 times. Return engine to idle. Fuel pressure
should not drop when engine is returned to idle.
5) Turn ignition off. Ensure fuel pressure reading does not
decrease within 2 minutes. If a decrease is noted, monitor speed of
decrease.
6) If fuel pressure is lower than specification, fuel
pressure drops at idle after increasing engine speed to 2500-3000 RPM,
or no fuel pressure in fuel return hose can be felt, check for clogged
fuel filter, or faulty fuel pressure regulator or fuel pump.
7) If fuel pressure is greater than specification, check for
a faulty fuel pressure regulator or plugged fuel return line. If fuel
pressure does not change when vacuum hose to regulator is connected or
disconnected, check for a leaking or clogged vacuum hose to fuel
pressure regulator or faulty fuel pressure regulator.
8) If fuel pressure decreases suddenly after engine is
stopped, check valve in fuel pump is not seated. Replace fuel pump. If
fuel pressure drops slowly, fuel injector is leaking or fuel pressure
regulator valve seat is leaking. Check for faulty fuel injector or
fuel pressure regulator. Repair as necessary.
9) When fuel pressure test is complete, repeat fuel pressure
release procedure before disconnecting fuel pressure gauge. Install
NEW "O" ring at end of high pressure fuel inlet line. Check for fuel
leaks.
FUEL PUMP PERFORMANCE TABLE
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At Idle w/Vacuum At Idle w/o Vacuum
Application psi (kg/cm) psi (kg/cm)
Eclipse 2.0L
Non-Turbo ........... ( 1) ............ 47-50 (3.3-3.5)
Turbo ............. 33 (2.3) ......... 42-45 (3.0-3.5)
3000GT Turbo ........ 34 (2.4) ......... 43-45 (3.0-3.1)
All Other Models .... 38 (2.7) ......... 47-50 (3.3-3.5)
( 1) - Information is not available from manufacturer at time
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G - TESTS W/CODES
1998 Mitsubishi Montero
1998 ENGINE PERFORMANCE
Mitsubishi - Self-Diagnostics
Montero & 3000GT
INTRODUCTION
* PLEASE READ THIS FIRST *
NOTE: If no faults were found while performing basic diagnostic
procedures in F - BASIC TESTING article, proceed with
self-diagnostics in this article. If no Diagnostic Trouble
Codes (DTCs) or only pass codes are present after entering
self-diagnostics, proceed to H - TESTS W/O CODES article for
diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.).
SYSTEM DIAGNOSIS
NOTE: PCM diagnostic memory is retained by direct power supply
from battery. Memory is not erased by turning off ignition,
but it will be erased if battery or PCM is disconnected.
System diagnosis can be accomplished using a scan tool. See
ENTERING ON-BOARD DIAGNOSTICS . Powertrain Control Module (PCM)
monitors several different engine control system circuits. If an
abnormal input signal occurs, a Diagnostic Trouble Code (DTC) is
stored in PCM memory and assigned a DTC number. Each circuit has its
own DTC number and message. A specific DTC indicates a particular
system failure, but does not indicate that cause of failure is
necessarily within system.
A DTC does not condemn any specific component; it simply
points out a probable malfunctioning area. If a DTC is set, PCM will
turn on MIL. System failures encountered are identified as either hard
failures or intermittent failures as determined by PCM.
Hard Failures
Hard failures cause MIL to come on and remain on until
failure is repaired. If MIL comes on and remains on (MIL may flash)
during vehicle operation, cause of failure may be determined by using
appropriate DTC diagnostic procedure. See TROUBLE CODE DEFINITION. If
a sensor fails, PCM will use a substitute value in its calculations to
continue engine operation. In this condition (limp-in mode), vehicle
is functional, but loss of good driveability may result.
Intermittent Failures
Intermittent failures may cause MIL to flicker, or come on
and go out after intermittent DTC goes away. However, corresponding
DTC will be retained in PCM memory. If related DTC does not reoccur
within a certain time frame, related DTC will be erased from PCM
memory. Intermittent failures may be caused by a sensor, connector or
wiring problems. See INTERMITTENTS in H - TESTS W/O CODES article.
The PCM also records and stores engine operating conditions
when malfunction occurred. This information is referred to as freeze
frame data. If malfunction is an engine misfire, or fuel system rich
or fuel system lean condition, freeze frame data will be updated with
the most current information regarding these failures. Freeze frame
data recorded is:
* Fuel System Status
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* Load Value (Displayed As Percent)
* Engine Coolant Temperature
* Short Term Fuel Trim (Displayed As Percent)
* Long Term Fuel Trim (Displayed As Percent)
* MAP Vacuum
* Engine RPM
* Vehicle Speed Sensor
* DTC During Data Recording
SELF-DIAGNOSTIC SYSTEM
SERVICE PRECAUTIONS
Before proceeding with diagnosis, following precautions must
be observed:
* Ensure vehicle has a fully charged battery and functional
charging system.
* Visually inspect connectors and circuit wiring being worked
on.
* DO NOT disconnect battery or PCM. This will erase any DTCs
stored in PCM.
* DO NOT cause short circuits when performing electrical tests.
This will set additional DTCs, making diagnosis of original
problem more difficult.
* DO NOT use a test light in place of a voltmeter.
* When checking for spark, ensure coil wire is NOT more than
1/4" from chassis ground. If coil wire is more than 1/4" from
chassis ground, damage to vehicle electronics and/or PCM may
result.
* DO NOT prolong testing of fuel injectors. Engine may
hydrostatically (liquid) lock.
* When a vehicle has multiple DTCs, always repair lowest number
DTC first.
VISUAL INSPECTION
Most driveability problems in the engine control system
result from faulty wiring, poor electrical connections or leaking air
and vacuum hose connections. To avoid unnecessary component testing,
perform a visual inspection before beginning self-diagnostic tests.
ENTERING ON-BOARD DIAGNOSTICS
NOTE: DO NOT skip any steps in self-diagnostic tests or incorrect
diagnosis may result. Ensure self-diagnostic test applies to
vehicle being tested.
DTCs may be retrieved by using a scan tool only. Proceed to
DTC retrieval method.
NOTE: Although other scan tools are available, Mitsubishi
recommends using Multi-Use Tester II (MUT II) scan tool.
Using Scan Tool
1) Refer to manufacturer's operation manual for instructions
in use of scan tool. Before entering on-board diagnostics, see
SERVICE PRECAUTIONS . Locate Data Link Connector (DLC) under instrument
panel, near steering column.
2) Turn ignition switch to OFF position. Connect scan tool to
DLC. Turn ignition switch to ON position. Read and record scan tool
self-diagnostic output. Proceed to TROUBLE CODE DEFINITION.
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TROUBLE CODE DEFINITION
When DTC is obtained, refer to appropriate DTC test
procedure.
DIAGNOSTIC TROUBLE CODES (DTCS)
NOTE: DTCs can only be retrieved by using a scan tool. Listed DTCs
are retrieved using a generic scan tool. MUT II scan tool
can be used, but it may not read all DTCs. DTCS listed are
not used on all vehicles.
DTC P0100
Volume Airflow (VAF) circuit failure. Possible causes are:
connector or harness, or faulty VAF sensor.
DTC P0105
Barometric (BARO) pressure circuit failure. Possible causes
are: connector or harness, or faulty BARO pressure sensor.
DTC P0105
Manifold Absolute Pressure (MAP) circuit failure. Possible
causes are: connector or harness, or faulty MAP sensor.
DTC P0110
Intake Air Temperature (IAT) circuit failure. Possible causes\
are: connector or harness, or faulty VAF sensor.
DTC P0115
Engine Coolant Temperature (ECT) circuit failure. Possible
causes are: connector or harness, or faulty ECT sensor.
DTC P0120
Throttle Position (TP) circuit failure. Possible causes are:
connector or harness, or faulty TP sensor.
DTC P0125
Excessive time to enter closed loop fuel control. Possible
causes are: faulty front HO2S, HO2S connector or harness, or faulty
fuel injector.
DTC P0130
Front Heated Oxygen Sensor (HO2S) circuit failure. Possible
causes are: connector or harness, or faulty HO2S.
DTC P0135
Front Heated Oxygen Sensor (HO2S) heater circuit failure.
Possible causes are: connector or harness, or faulty HO2S.
DTC P0136
Rear Heated Oxygen Sensor (HO2S) circuit failure. Possible
causes are: connector or harness, or faulty HO2S.
DTC P0141
Rear Heated Oxygen Sensor (HO2S) heater circuit failure.
Possible causes are: connector or harness, or faulty HO2S.
DTC P0150
Heated Oxygen Sensor (HO2S) circuit failure (bank 2, sensor
1). Possible causes are: connector or harness, or HO2S.
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purge control valve, or vacuum hose routing.
DTC P0443
Evaporative (EVAP) purge control valve circuit failure.
Possible causes are: connector or harness, or faulty EVAP solenoid.
DTC P0446
Evaporative (EVAP) emission control system vent control
failure. Possible causes are: connector or harness, faulty EVAP vent
solenoid.
DTC P0450
Evaporative (EVAP) emission control system pressure sensor
failure. Possible causes are: connector or harness, or faulty fuel
tank differential pressure sensor.
DTC P0455
Evaporative (EVAP) emission control system large leak
detected. Possible causes are: connector or harness, faulty EVAP purge
solenoid, purge control valve, or vacuum hose routing.
DTC P0500
Vehicle Speed Sensor (VSS) failure. Possible causes are:
connector or harness, or faulty VSS.
DTC P0505
Idle Air Control (IAC) system failure. Possible causes are:
connector or harness, or faulty IAC motor.
DTC P0510
Closed Throttle Position (TP) switch failure. Possible causes\
are: connector or harness, or faulty closed TP switch.
DTC P0551
Power Steering Pressure (PSP) sensor failure. Possible causes\
are: connector or harness, or faulty PSP sensor.
DTC P0705
Automatic transaxle/transmission range sensor circuit
failure. Possible causes are: connector or harness, or faulty PNP
switch.
DTC P0710
Automatic transaxle/transmission fluid sensor failure.
Possible causes are: connector or harness, or faulty
transaxle/transmission sensor.
DTC P0715
Automatic transaxle input/turbine speed sensor circuit
failure. Possible causes are: connector or harness, or pulse
generator.
DTC P0720
Automatic transaxle input/turbine speed sensor circuit
failure. Possible causes are: connector or harness, or pulse
generator.
DTC P0725
Engine speed input circuit failure. Possible causes are:
connector or harness.
DTC P0740
Torque converter clutch system failure. Possible causes are:
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connector or harness, or torque converter clutch solenoid.
DTC P0750
Shift solenoid "A" failure. Possible causes are: connector or
harness, or low-reverse solenoid.
DTC P0755
Shift solenoid "B" failure. Possible causes are: connector or
harness, or underdrive solenoid.
DTC P0760
Shift solenoid "C" failure. Possible causes are: connector or
harness, or second solenoid.
DTC P0765
Shift solenoid "D" failure. Possible causes are: connector or
harness, or overdrive solenoid.
DTC P1103
Turbocharger wastegate actuator failure. Possible causes are:
connector or harness, faulty wastegate solenoid or actuator, or vacuum
hose routing.
DTC P1104
Turbocharger wastegate solenoid failure. Possible causes are:
connector or harness, or faulty wastegate solenoid.
DTC P1105
Fuel pressure solenoid failure. Possible causes are:
connector or harness, or faulty fuel pressure solenoid.
DTC P1400
Manifold Differential Pressure (MDP) sensor circuit failure.
Possible causes are: connector or harness, or faulty MDP sensor.
DTC P1500
Generator FR terminal circuit failure. Possible causes are:
connector or harness.
DTC P1600
Serial communication link failure. Possible causes are:
connector or harness.
DTC P1715
Pulse Generator (PG) failure. Possible causes are: connector
or harness, or faulty PG.
DTC P1750
Solenoid failure. Possible causes are: connector or harness,
faulty converter clutch solenoid, shift control solenoid, or pressure
control solenoid.
DTC P0751
Automatic transaxle control relay failure. Possible causes
are: connector or harness, or automatic transaxle relay.
DTC P1791
Engine coolant temperature level input circuit (to TCM)
failure. Possible causes are: connector or harness.
DTC P1795
Throttle position input circuit failure. Possible causes are:
connector or harness.
Page 745 of 1501
PCM or performing resistance tests.
NOTE: Perform all resistance and voltage tests using a Digital
Volt-Ohmmeter (DVOM) with a minimum 10-megohm impedance,
unless stated otherwise in test procedures.
Using scan tool, display and record Diagnostic Trouble DTCs
(DTCs). See ENTERING ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC
SYSTEM. If scan tool is blank, see SCAN TOOL WILL NOT COMMUNICATE. If
no DTCs are displayed, see H - TESTS W/O CODES article.
Clear DTCs. See CLEARING DTCS under SELF-DIAGNOSTIC SYSTEM.
Road test vehicle (if necessary) and attempt to duplicate conditions
that caused original complaint. Recheck for DTCs. If no DTCs are
displayed, go to INTERMITTENT DTCS. If one or more DTCs are displayed,
repair DTCs in order, starting with lowest numbered DTC. Clear DTCs
after each repair. Recheck for DTCs to confirm repair.
SCAN TOOL WILL NOT COMMUNICATE
NOTE: For terminal identification, see TERMINAL IDENTIFICATION. For
circuit and wire color identification, see
L - WIRING DIAGRAMS article.
1) Using DVOM, check voltage between Data Link Connector
(DLC) terminal No. 16 and chassis ground. If battery voltage does not
exist, check and repair junction connectors and wiring harness between
DLC and power supply.
2) If battery voltage exists, check for continuity between
DLC terminal No. 4 and chassis ground, and between DLC terminal No. 5
and chassis ground. If continuity does not exist, check and repair
wiring harness between DLC and chassis ground. If continuity exists,
go to next step.
3) Try a different scan tool adapter cable. If scan tool does
not communicate, try scan tool on a known-good vehicle. If scan tool
still does not communicate, replace scan tool.
INTERMITTENT DTCS
This procedure applies if you have been sent here from
diagnostic tests and have just attempted to simulate the condition
that initially set DTC. The following additional checks may assist in
identifying a possible intermittent problem:
* Visually inspect related wiring harness connectors for
broken, bent, pushed out or corroded terminals.
* Visually inspect related wiring harness for chafed, pierced
or partially broken wires.
* Check all pertinent technical service bulletins.
DTC P0100: VOLUME AIRFLOW (VAF) SENSOR CIRCUIT FAILURE
NOTE: For terminal identification, see TERMINAL IDENTIFICATION. For
circuit and wire color identification, see
L - WIRING DIAGRAMS article.
NOTE: Procedures are provided by manufacturer for component
testing using an engine analyzer with oscilloscope
capability. Refer to manufacturer's operation manual for
instructions in use of oscilloscope.
1) If using scan tool, go to step 3). Disconnect VAF sensor
connector. Install Test Harness (MB991348) between VAF sensor and
connector. Using engine analyzer with oscilloscope capability, connect
Page 746 of 1501
special patterns probe to VAF sensor connector terminal No. 3 or to
PCM connector terminal No. 61.
2) Start engine. Verify waveform high frequency and low
frequency patterns are of about the same length (time). Verify
wavelength decreases and frequency increases as engine RPM increases.
If conditions are not as specified, replace VAF sensor. If conditions
are as specified, go to step 4).
3) Warm vehicle to normal operating temperature. Ensure
headlights and accessories are off. Using scan tool, read VAF sensor
frequency value (item 12). See VOLUME AIRFLOW SENSOR VALUES table.
Frequency should increase when engine is raced. If values are not as
specified, replace VAF sensor. If values are as specified, turn
ignition switch to off position and disconnect VAF sensor connector.
Go to next step.
VOLUME AIRFLOW SENSOR VALUES TABLE
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Application Hz @ 700 RPM Hz @ 2500 RPM
Montero ................. 25-51 ................. 80-120
3000GT
DOHC
Non-Turbo ........... 24-50 ................. 71-111
Turbo ............... 26-52 ................. 93-133
SOHC .................. 21-47 .................. 57-97
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4) On 3000GT, go to next step. On Montero, disconnect MFI
relay connector. Using DVOM, check for continuity between VAF sensor
connector terminal No. 4 and MFI relay connector terminal No. 1. If
continuity does not exist, repair wiring harness as necessary. If
continuity exists, go to next step.
5) Using DVOM, check for continuity between chassis ground
and VAF sensor connector terminal No. 5. If continuity does not exist,
repair wiring harness as necessary. If continuity exists, go to next
step.
6) Ensure ignition switch is in OFF position. Disconnect PCM
connector. Ground PCM connector terminal No. 19. Using DVOM, check for
continuity between chassis ground and VAF sensor connector terminal
No. 7. If continuity does not exist, repair wiring harness as
necessary. If continuity exists, go to next step.
7) On 3000GT, go to next step. On Montero, ground PCM
connector terminal No. 61. Using DVOM, check for continuity between
chassis ground and VAF sensor connector terminal No. 3. If continuity
does not exist, repair wiring harness as necessary. If continuity
exists, turn ignition switch to ON position and go to step 9).
8) Turn ignition switch to ON position. Using DVOM, check
voltage between chassis ground and VAF sensor connector terminal No.
4. If battery voltage does not exist, repair wiring harness as
necessary. If battery voltage exists, go to next step.
9) Using DVOM, check voltage between chassis ground and VAF
sensor connector terminal No. 3. If voltage is not 4.8-5.2 volts,
replace PCM. If voltage is as specified, condition required to set DTC
is not present at this time. Go to next step.
10) Test is complete. Intermittent problem may exist. Road
test vehicle (if necessary) and attempt to duplicate conditions that
caused original complaint. Recheck for DTCs. If no DTCs are displayed,
go to INTERMITTENT DTCS .
DTC P0105: BAROMETRIC (BARO) PRESSURE SENSOR CIRCUIT FAILURE
NOTE: BARO pressure sensor is built into Volume Airflow (VAF)
sensor. For DTC P0105 test purposes, VAF sensor will be
Page 747 of 1501
referred to as BARO pressure sensor. For terminal
identification, see VAF sensor under TERMINAL IDENTIFICATION.
For circuit and wire color identification, see
L - WIRING DIAGRAMS article.
1) Component testing procedure without using scan tool not
available from manufacturer at time of publication. Turn ignition
switch to ON position. Using scan tool, read BARO sensor pressure
(item 25). See BARO PRESSURE SENSOR SPECIFICATIONS table. If pressure
is not as specified, replace BARO pressure sensor. If pressure is as
specified, go to next step.
BARO PRESSURE SENSOR SPECIFICATIONS TABLE
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Altitude in Ft. (M) Pressure in kPa (mmHg)
0 (0) .......................................... 101 (768)
1969 (600) ...................................... 95 (710)
3937 (1200) ..................................... 88 (660)
5906 (1800) ..................................... 81 (610)
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2) Disconnect BARO pressure sensor connector. Using DVOM,
check for continuity between chassis ground and BARO pressure sensor
connector terminal No. 5. If continuity does not exist, repair wiring
harness as necessary. If continuity exists, go to next step.
3) Turn ignition switch to OFF position. With BARO pressure
sensor disconnected, disconnect PCM connector. Ground PCM connector
terminal No. 51. Using DVOM, check for continuity between chassis
ground and BARO pressure sensor connector terminal No. 2. If
continuity does not exist, repair wiring harness as necessary. If
continuity exists on Montero, go to next step. On 3000GT, go to step
5).
4) Ground PCM connector terminal No. 42. Check for continuity
between chassis ground and BARO pressure sensor connector terminal No.
1. If continuity does not exist, repair wiring harness as necessary.
If continuity exists, go to next step.
5) Reconnect PCM connector. With BARO pressure sensor
connector disconnected, turn ignition switch to ON position. Using
DVOM, check for voltage between chassis ground and BARO pressure
sensor connector terminal No. 1. If voltage is not 4.8-5.2 volts,
replace PCM. If voltage is as specified, condition required to set DTC
is not present at this time. Go to next step.
6) Test is complete. Intermittent problem may exist. Road
test vehicle (if necessary) and attempt to duplicate conditions that
caused original complaint. Recheck for DTCs. If no DTCs are displayed,
go to INTERMITTENT DTCS .
DTC P0110: INTAKE AIR TEMPERATURE (IAT) SENSOR CIRCUIT
FAILURE
NOTE: IAT sensor is built into Volume Airflow (VAF) sensor. For
DTC P0110 test purposes, VAF sensor will be referred to as
IAT sensor. For terminal identification, see VAF sensor
under TERMINAL IDENTIFICATION . For circuit and wire color
identification, see L - WIRING DIAGRAMS article.
1) If using scan tool, go to step 3). Disconnect IAT sensor
connector. Using a thermometer, check engine compartment ambient
temperature. Using DVOM, check resistance between IAT sensor terminals
No. 5 and 6. Resistance should be 6000 ohms at 32
F (0C), 2700 ohms
at 68F (20C) or 400 ohms at 176F (80C). If resistance is not as
specified, replace IAT sensor. If resistance is as specified, go to
Page 748 of 1501
next step.
2) Using a hair dryer, warm IAT sensor while monitoring DVOM.
Resistance should decrease evenly as temperature rises. If resistance
remains unchanged, replace IAT sensor. If resistance changes, go to
step 4).
3) Turn ignition switch to ON or RUN position. Using a
thermometer, check engine compartment ambient temperature. Using scan
tool, read IAT sensor temperature (item 13). Compare both readings. If\
readings are not about the same, replace IAT sensor. If readings are
about the same, turn ignition off and go to next step.
4) Disconnect IAT sensor connector. Using DVOM, check for
continuity between chassis ground and IAT sensor connector terminal
No. 5. If continuity does not exist, repair wiring harness as
necessary. If continuity exists, go to next step.
5) On 3000GT, go to next step. On Montero, turn ignition
switch to OFF position. With IAT sensor connector disconnected,
disconnect PCM connector. Ground PCM connector terminal No. 62. Check
for continuity between IAT sensor connector terminal No. 6 and chassis
ground. If continuity does not exist, repair wiring harness as
necessary. If continuity exists, go to next step.
6) Reconnect PCM connector. Turn ignition switch to ON
position. Check voltage between IAT sensor connector terminal No. 6
and chassis ground. If voltage is not 4.5-4.9 volts, replace PCM. If
voltage is as specified, replace IAT sensor.
DTC P0115: ENGINE COOLANT TEMPERATURE (ECT) SENSOR FAILURE
NOTE: For terminal identification, see TERMINAL IDENTIFICATION. For
circuit and wire color identification, see
L - WIRING DIAGRAMS article.
1) If using scan tool, go to step 2). Disconnect ECT sensor
connector. Remove ECT sensor from intake manifold. Submerge
temperature sensing portion of ECT sensor in hot water. Using DVOM,
check resistance across ECT sensor terminals. See
ECT SENSOR RESISTANCE SPECIFICATIONS table. If resistance is not as
specified, replace ECT sensor. If resistance is as specified, go to
step 3).
ECT SENSOR RESISTANCE SPECIFICATIONS TABLE
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Water Temperature Approximate Resistance in Ohms
32
F (0C) .......................................... 5800
68F (20C) ......................................... 2400
104F (40C) ........................................ 1100
176F (80C) ......................................... 300 \
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2) Turn ignition switch to ON or RUN position. Using a
thermometer, check engine compartment ambient temperature. Using scan
tool, read ECT SENSOR TEMPERATURE (item 21). Compare both readings. If\
readings are not about the same, replace ECT sensor. If readings are
about the same go to next step.
3) Disconnect ECT sensor connector. Using DVOM, check
continuity between chassis ground and ECT sensor connector terminal
No. 2. If continuity does not exist, repair wiring harness as
necessary. If continuity exists on 3000GT, go to step 5). On Montero,
go to next step.
4) Turn ignition switch to OFF position. With ECT sensor
connector disconnected, disconnect PCM connector. Ground PCM connector
terminal No. 44. Check continuity between chassis ground and ECT
sensor connector terminal No. 1. If continuity does not exist, repair