1993 MITSUBISHI 3000GT check engine light

Downloaded from www.Manualslib.com manuals search engine CHASSIS ELECTRICAL - Meters and Gauaes
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ENGINE COOLANT TEMPERATURE GAUGE SIMPLE CHECKConnect the harness connector via a
test light to the ground.
Remove the water temperature gauge
unit coupling connector.
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Place the ignition switch in the ON posi-tion.
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(12 v’3.4 w) \ //Z16FO13lCheck the test light and gauge conditions.
i(1) Test light lights. (Pointer of gauge does not swing.)_____c Replace water temperature gauge.
[ (2) Test light lights. (Pointer of gauge swings.)Replace water temperature gauge unit.
[ (3) Test light does not light. (Pointer of gauge does not swing.)/-------I Correct harness.
ENGINE COOLANT TEMPERATURE GAUGE UNIT CHECK
To check, remove engine coolant temperature gauge unit from
the thermostat housing.
Engine Coolant Temperature Gauge Unit Resistance
(1)Immerse unit in 70°C (158OF) water to measure resistance.Standard value: 104
f 13.5 Sz(2) After checking, apply the specified sealant around the
thread of engine coolant temperature gauge unit and install
on the thermostat housing.
Specified sealant:3M Nut Locking Part No. 4171 or equivalent
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Downloaded from www.Manualslib.com manuals search engine 54-30CHASSIS ELECTRICAL - Meters and Gauges
OIL PRESSURE GAUGE SIMPLE CHECKRemove the oil pressure gauge unit
coupling connector.Connect the harness connector via a
test light to the ground.
-1Place the ignition switch in the ON posi-Check the test light and gauge conditions.
(1) Test light lights. (Pointer of gauge does not swing.)
k-1 Replace oil pressure gauge.
1 (2) Test light lights. (Pointer of gauge swings.)k-1 Replace oil pressure gauge unit.
1 (2) Test light does not light. (Pointer of gauge does not swing.)/-1 Correct harness.
VOLTAGE GAUGE SIMPLE CHECKCheck voltage gauge for conditions.
(1) Voltage indicated by voltmeter differs from voltage indicated by
voltage gauge (position indicated by pointer).
-1 Replace gauge.
(2) Gauge does not operate.
/--I Correct harness or replace gauge.
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Downloaded from www.Manualslib.com manuals search engine 54-36CHASSIS ELECTRICAL - Lighting System
SPECIAL TOOLS
ToolTool number and name
1 ROM Pack
MB991 529Diagnostic trouble code
check harness
Supersession
MB991 341 C
Application
Up to 1993 models
Checking the lighting system
MB991 502All models
Checking the lighting system
MB991 529From 1994 modelsChecking the lighting system
using a voltmeter
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Downloaded from www.Manualslib.com manuals search engine CHASSIS ELECTRICAL - Liahting System
TROUBLESHOOTING
Check the light aut
Refer to
P.54-108.
headlights is normal.
Taillights are not automati-
Check the driver’ssidedoor switch.tally
shut off either.
NOTE(1) *Up to 1993 models
(2) For information concerning the theft-alarm system, refer to
P.54-222.
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Downloaded from www.Manualslib.com manuals search engine INPUT SIGNALWith voltmeterData link connector
Ii ri7-11
When using the scan tool (MUT) or voltmeter‘d
Using the scan tool or voltmeter, check whether or not the
input signals from each switch are being input to the ETACS
unit.
54-56CHASSIS ELECTRICAL - Lighting System
(1) Connect the scan tool to the data link connector located
at the right side of the junction block or connect the voltme-
ter between the ETACS terminal and the ground terminal.
(2) Check if the buzzer of the scan tool sounds or the needle
of the voltmeter moves when each switch is operated.
If the buzzer sounds or the needle moves, the input signalsare being input to the ETACS unit, so that switch can
be considered to be functioning normally. If not, the switch
or switch input circuit is faulty. Check the switch and the
switch input circuit.
When using the MUT-II
CUP to 1993 models>
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When using the scan tool (MUT-II)
(1) Connect the scan tool to the data link connector. When
connecting the scan tool to a vehicle up to 1993 models,
use the adapter harness supplied together.‘dCaution
Turn off the ignition switch beforehand whenever the
scan tool is connected or disconnected.
(2) If the scan tool makes a peep sound when each switchis operated (turned ON/OFF), the input signal to ECU
is normally sent from the switch circuit system.
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When using the voltmeter
(1)Connect a voltmeter to the ETACS terminal and the ground
terminal of the data link connector using the special tool.
(2) If the voltmeter pointer deflects once when each switchis operated (turned ON/OFF), the input signal to ECU
is normally sent from the switch circuit system.
do
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Downloaded from www.Manualslib.com manuals search engine 54-62CHASSIS ELECTRICAL - Lighting System
OPERATION
lWhen the fog light switch is placed in the ON position with the lighting switch in the HEAD positionand the dimmer switch in the LO position, current flows through the dedicated fuse (4) to the coil
of the fog light relay, the fog light switch, the dimmer switch and ground, causing the contacts of
the fog light relay to close.
When the contacts of the fog light relay close, current flows through the dedicated fuse (4) to the
contacts of the fog light relay, the fog lights and ground, causing the fog lights to come on.
lWhen the dimmer switch is placed in the HI position or the lighting switch is placed in the TAIL or
OFF position while the fog lights are ON, current supply to the fog light relay or headlight relay is
cut off. As a result, the contacts of the fog light relay open, and the fog lights go out.
NOTE
The fog lights are included in the light automatic shut-OFF system. (Refer to P.54-37). The indicator lights
are also included in the same system.
Fog Lights Operation Conditions
Fog light switchLighting switchDimmer switchFog lights
ON position
1 OFF position or TAIL posi- 1 LO position1 OFF
tion
HEAD positionHI position
LO position
OFF
ON
HI position
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OFF
TROUBLESHOOTING HINTS1. The right or left fog lights only go on.
0Check the bulb.2. Fog lights do not go on when the fog light switch is set at ON.
0Check the dedicated fuse (4).
0Check the fog light relay. (Refer to P.54-108).
0Check the fog light switch.
NOTEFor the light automatic shut-OFF system troubleshooting hints, refer to
P.54-38.
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Downloaded from www.Manualslib.com manuals search engine 54-70CHASSIS ELECTRICAL - Lighting System
OPERATION
0When the lighting switch is placed in the TAILor HEAD position, current flows through the
coil of the tail light relay to the lighting switchand ground, causing the contacts of the tail
light relay to close.
Then current flows through the contacts of thetail light relay to the dedicated fuse
(2) the
individual lights and ground, causing the tail
lights, parking/side marker lights and licenseplate lights to go ON.

lIf the driver’s door is opened after the ignition
switch is turned to “OFF” or the ignition switchis turned to “OFF” after the driver’s door is
opened when the tail lights are lit, the current
which flows to the coil side of the tail light relaywill be cut off by the light automatic shut-off
unit opening the contact point, and the tail light
relay will be turned “OFF’ to automatically shut
off the tail lights, parking and front side marker
lights and license plate light.
lTo turn on the tail lights, parking and front side
marker lights and license plate light again after
they are automatically shut off, turn the lightingswitch to “OFF” once and to “HEAD” again,
or turn the ignition switch to “ACC” or “ON”,
and the automatic shut-OFF will be cancelled
and the current will flow from the light automaticshut-OFF unit to the coil side of the tail light
relay to close the contact point. Thus, the taillight relay will be turned “ON” to turn on the
tail lights, parking and front marker lights and
license plate light.
NOTE
When the lighting switch is at the “HEAD” position,
the light automatic shut-OFF system will be also
activated for the headlights. (Refer to P.54-37.) The
same system will also be activated for the illumina-
tion lights, etc.
TROUBLESHOOTING HINTS1. All lights don’t illuminate.
(1) The headlights don’t illuminate, either.l Check the fusible link (3).
(2) The headlights illuminate.l Check the tail light relay. (Refer to
P.54-108.)l Check the dedicated fuse (2).
l Check the lighting switch. (Refer to
P.54-113.)l Check the light automatic shut-OFF
unit. (Refer to
P.54-108.)2. Some light does not come on.
l Check the bulb.
l Check the grounding circuit.
3. Some light is not automatically shut off.
lCheck the driver’s side door switch.
(Refer to GROUP 42- Door Assembly.)l Check the automatic shut-OFF unit.
(Refer to
P.54-108.)
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Downloaded from www.Manualslib.com manuals search engine 54-78CHASSIS ELECTRICAL - Lighting System
OPERATION light>l
Battery voltage is always applied to the dome light. When the dome light switch is turned to “ON”,
the dome light will remain lit. After either door is opened if the dome light switch is at “DOOR” position,the dome light will come on.
lWith the dome light turned on (with the ignition switch in the OFF position and with the dome light
switch in the DOOR position), close all doors, and the timer circuit in the ETACS unit will be activatedto gradually vary the voltage for approx. 6 seconds owing to the duty control, and the voltage will
be output to transistor Tr. Since the voltage applied to the dome light gradually decreases, the dome
light will be dimmed.lIf the ignition switch is turned to “ON” while the dome light is lit (while the timer is activated), the
timer circuit will be opened to turn “OFF” transistor Tr. This will immediately turn off the dome light
without dimming. light>-lBattery voltage is always applied to the foot lights and ignition key illumination light.
With the ignition switch in the OFF position, open any door, and all lights will come on.
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With all lights turned on (with the ignition switch in the OFF position), close all doors, and the timercircuit inside the ETACS unit will operate in the same manner as the dome light to dim all lights.
When the ignition switch is placed in the ON position with all lights turned on (with the timer in operation),the same operation as the dome light will take place.
TROUBLESHOOTING HINTS
Phenomenon
Dome light does not come on
when
a door is opened with the
dome light switch in the DOOR
position.
Check the door switch input signal.
Check the door switch. (Refer to GROUP 42 -
The foot lights and ignitionl
key cylinder illumination
Check the dome light switch.
light illuminate.
lCheck the dome light bulb.
Dome light, foot lights and ignition key illumination light go out
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at once when doors are closed.Check the door switch input signal.(Refer to P.54-80.)Even if ignition switch is turned on while lights are being
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dimmed,lightsdo notout at the same time.
Check the ignition switch input signal.
go
(Refer toP.54-80.)
COMPONENT LOCATION
Data ‘link
connect&
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