NISSAN 300ZX 1984 Z31 Electrical System Repair Manual

METER AND GAUGES - Digital Type Combination Meter
Trou ble-sho
Go to "Display Check"
OK
Go to "Power Unit Check"
T
Replace meter and
gauge assembly Replace power unit
T Replace meter and gauge assembly
ng (Cont'd)
Only water temp gauge does not operate
I
Go to "Display Check"
T
OK
Replace meter and
gauge assembly
Check water temp sensor (thermistor) Circuit
OK NG
Replace meter
and gauge
assembly
Check harness between Replace
thermistor and meter thermistor
1 Disconnect meter harness connector
2
3
(black)
Turn ignition swltch to "OFF"
Measure resistance between 0 and @
!'W I 1 Ohmmeter
ignition switch - OFF
Resistance
70CI or more
6O'C or more Approx 10 - 70R
SEL6710
EL-51

METER AND GAUGES - Digital Type Combination Meter
Trouble-shooting (Cont’d)
Go to “Displav Check”
ING OK
Replace meter and
gauge assembly
v
Check oil pressure sensor circuit
OK NG
Go to “Oil Pressure
Sensor Check” Replace meter
and gauge
assembly
Check harness between Replace oil
oil pressure sensor and meter pressure
sensor
1 Disconnect meter harness connector
(black)
2 Measure resistance between @ and @
when engine stopping and running
Ohmmeter
Engine Resistance
Approx 75R or more
Idling Approx 60R or less
SEL672D
“Trip”, ”Ave speed” and “Dist to empty” meters
1 Go to ”Display Check” 1
Go to “Power Unit Check”
Replace trip Replace power unit
meter assembly
Only “Ave speed” meter does not operate
I
I Go to “Display Check“ I
lNG
OK
Replace trip
meter assembly
I Check clock for proper operation I
Check harness between Replace clock
clock and meter
I OK v
Replace trip meter assembly

METER AND GAUGES - Digital Type Combination Meter
Power Unit Check
Voltmeter
terminal
(f) (-)
E -
-%; 0
0
@I
__
@
9
0
0
Remove power unit with harness connected
Perform voltage and continuity tests Refer to
chart below
I Voltage
[VI
Approx 12
Approx 5
Approx 16
Approx 5
Approx 22
Approx 285
Turn ignition switch to "ON"
1 - 1 More than 6
Remarks
Check when no
display appears
For speedometer
For tachometer
For Temp,
Oil, Volt
sause
For Fuel gauge
For "Trip", "Ave
speed"
& "Dirt to
empty" meter
Turn ignition switch to "OFF"
Ohmmeter
Continuity Remarks
Check when no
ground display appears
If specified voltage or continuity is not produced,
replace power unit.
- Boost Sensor Check
1 Connect vacuum pump gauge to boost sensor
vacuum hose
2 Disconnect harness connector from boost
sensor and connect battery and voltmeter
as
shown
3 Apply vacuum pressure to boost sensor by
vacuum pump gauge and measure voltages
Approx.
2.2V at 0 kPa (0 mmHg, 0 inHg)
(Atmospheric pressure)
Approx.
1 3V
at -53.3 kPa (-400 mmHg, -15 75 inHg)
vacuum pump gauge
SEL674D
EL-53

METER AND GAUGES - Digital Type Combination Meter
Speed Sensor Signal Check
SPEED SENSOR OUTPUT CHECK
When speedometer
is functioning properly, this
test
is not necessary. Go to "Meter Output check"
1 Remove cluster lid A
2 Connect a voltmeter between @ and @ on
cornbination meter side. Combination meter
harness connector should remain connected to
instrument harness
Switch ignition switch from "OFF" to
"ON"
Voltmeter should indicate approximately 5
volts when switch is "ON"
If voltmeter indicates no voltage, go to "Power
Unit Check".
3
SEL745D
4
5
Turn ignition switch to "OFF"
Disconnect speedometer cable from speed
sen-
sor and remove speed sensor with harness con-
nected.
6. Disconnect combination meter harness from
instrument harness
as shown below, and con-
nect
a voltmeter across @ and @
Voltmeter SEL746D
7
8
Turn ignition switch "OFF" + "ON"
Slowly turn speed sensor rotor shaft with a
suitable screwdriver to make sure voltmeter
pointer deflects
Do not turn rotor shaft quickly as voltmeter
deflects
24 times per revolution of rotor shaft
SEL747D
If voltmeter pointer does not deflect, replace speed
sensor.
EL-54

METER AND GAUGES - Digital Type Combination Meter
Speed Sensor Si!
METER OUTPUT CHECK
Combination meter emits speed sensor signal to
control
E C.C.S. control unit, A.S.C D. control
unit, voice warning
unit and AIT control unit.
Disconnect speedometer cable from speed sen-
sor and remove speed sensor with harness con-
nected 1
2 Remove cluster lid A.
3 Disconnect combination meter harness from
instrument harness
as shown, and connect an
ohmmeter between @ and 0
Ohmmeter
SEL748D
11 Check (Cont'd)
4
5
Turn ignition switch "OFF" + "ON".
Slowly turn speed sensor rotor shaft with a
suitable screwdriver to make sure ohmmeter
pointer deflects.
Ohmmeter pointer deflects twice for each rotatton
of rotor shaft
Ohmmeter -
SEL7490
If ohmmeter pointer does not deflect, go to
"Speed Sensor Output Check". (Refer to back
paw)
EL-55

METER AND GAUGES - Digital Type Combination Meter
Fuel Tank Gauge Check
For removal, refer to FE section
Ohmmeter terminal Float
Main gauge
Resistance value
Approx 10 - 20Q
Approx 480 - 520Q
Approx 100 - 1 1 OQ
Approx 4Q or below
Approx
870.930Q
Sub gauge
SEL675D
SEL676D
-Water Temp Sensor Check -
Cylinder head R H side
SEL677D
-Oil Pressure Sensor Check -
-
011 filter 7 \
SEL678D
Ohmmeter
terminal With engine With engine
stopped 1 running (idling)
ca On
+I;'''' I More than 74Q I Less than 60.Q
EL-56

METER AND GAUGES -Digital Type Combination Gauge
Combination Gauge
CAUTION:
Never touch the combination gauge terminal with bare hands
Digital type combination gauge should not be disassembled
ON or START IGNITION SWITCH
FUSE ~
PFUSE L-l
I
1
ACCELERATION
ILLUMINATION
EL-57

METER AND GAUGES -Digital Type Combination Gauge
Wiring Diagram
lOUlN03
m m
.? I
@q .
w-@ I I
SEL680D
EL-58

METER AND GAUGES -Digital Type Combination Gauge
Trouble-shooting
(+)
v
Check power supply circuit for combination
gauge
(-1
l°K 1 NG
Replace combination gauge Check harness
Voltmeter terminal I Ignition switch position
Approx Approx
@ I 03 I OV I 12v ! 12v
Continuity exists @ I gK:d I
Remove radio and A/C control assembly from
center console and remove combination gauge
with harness connected
Check from harness rtde
SEL681D
Display illumination will not darken when light
1 switch is "ON"
I Check light switch circuit for combination gauge I
1 Remove radio and A/C control assembly
and remove combination gauge with har-
ness connected.
Turn ignition switch to
"OFF"
Turn light switch to "ON"
Measure voltage across @ and @
2
3
4
Ignition switch - 0
ht switch - ON
SEL682D L
EL-59

METER AND GAUGES -Digital Type Combination Gauge
,- Trouble-shooting (Cont'd)
Compass will not indicate direction in which vehicle is being driven COMPASS
I
Face vehicle toward the North to make sure arrow points to "N"
Display deviates
by one graduation
. more graduations
Display deviates by two or
. 1 SIOWI~ turn volume 0 until arrow moves from
@ (0) to @ (@I Thenslowlyreturn
volume
@ until arrow points to point @
When arrow deviates toward West, move switch
@ to (+),when it deviates toward the East,
move switch to
(-) Return switch @ to
Neutral when arrow stays between points
@)
and @
I Face vehicle toward the East to make sure arrow points to "E" 1
Display deviates
SIOWIV turn volume @ until arrow moves from
(Q (0) to @ (@I Then slowly return
volume
@ until arrow points to point @
1 Display deviates by two or
. more graduations
switch @to (+I, when it deviates toward the
South, move switch
to (4 Return switch @
to Neutral when arrow stays between points
(Q and 0
I Again face vehicle toward the North to make sure arrow points to "N" 1
Direction sensor amplifier (Located on luggage compartment R H 1 , ,
Dirplav
SEL683D SEL684D
EL-60