1998 NISSAN GT-R relay

FULLY AUTOMATIC AIR CONDITIONER
System Description
The fully automatic air conditioner system utilizes sensors to detect the in-vehicle temperature, ambient
temperature, temperature of air passing through the evaporator, and
sunload. The detected values are
compared with the temperature adjustment dial setting, and calculated by the microcomputer within the
automatic amplifier. The air inlet and outlet temperatures and airflow rate are adjusted in order to main-
@ tain the in-vehicle temperature.
When an abnormal pressure occurs within the cooler cycle [gauge pressure: approx.
2.7 MPa (28 kg/
cm2G)
or higher; or approx. 0.18
MPa
(1.8
kg/cm2-G)
or lower] the refrigerant pressure sensor operates,
Ec
and stops the compressor.
The
ECM turns off the air conditioner relay, and stops the compressor during engine high load.
The blower fan motor utilizes
a brushless motor, and controls the airflow with a built-in IC that recognizes AT
the driver signal (pulse) from the automatic amplifier.
Step-motor type actuators are employed for intake door, mode door, and air mix door. They are rotated in
response to the signal (pulse) step quantity transmitted from the automatic amplifier to control the target
BR
door position.

FULLY AUTOMATIC AIR CONDlTlONER
Component Parts Location
Intake door actua:or
,
Sunload sensor
Controller
B&wer temperature sensor
fan motor
@ Radiator core lower support I
Front defros!er grille (left)
1 ,?efros:er gnlie (left) t I
0 Blower fan motor relay
Engine room, right relay box I / Air conditioner relay I
Blower and cooling unit
I Blower fan motor
? Ar condlboner relay
@ Refrigerant
pressure sensor @ Compressor @ Ambtent sensor
a Liquid tank I @ Englne room. front left
I
Blower and cooling unit
lnta Instrument panel, center I
7 IJj Cluster
lid A 0 Fuse block, rear face 1

FULLY AUTOMATIC AIR CONDITIONER
Circuit
Diagram
Blower tan motor relay
Rear defogger
A Combination meter (meter UU) output * I Rear defogger relay - Rear defogger display inpui
I Compressor
Blower
fan driver signal Refrigerant Pressure sensor
Actuator driver power source
lntake driver
1 lntake driver 2 lntake driver 3 lntake driver 4
lntake door actuator NP ON output NP display input
Lighting
SW (1 step)
Y-lkEka Air mix door actuator
Illumination
power
source
Air mix driver 1 Air mrx drive: 2 Air mix driver 3 Air mix driver 4
Mode driver 1 1 Mode driver 2 Mode driver 3 Mode driver 4
INCAR In-vehicle sensor
Ambienl sensor
Sunload sensor
AM B
Water TEMP
SUN
INTAKE
Sensor around
lluminatron
groun:!
iND
Automatic
amp!iher

FULLY AUTOMATIC AIR CONDITIONER
Magnet Clutch System Check
MAGNET CLUTCH
Disconnect the compressor connector. Apply approx. 12V to the compressor to check the magnet clutch
operation.
/;sn
AIR CONDITIONER RELAY QJg
Remove the air conditioner relay. Apply approx. 12V between the air conditioner relay terminals No. 1 and
2. Check the relay operation sound. Ec Check the continuity between terminals No. 3 and 5.
REFRIGERANT CHARGE AMOUNT AT
Connect the manifold gauge to the vehicle side service valve.
Check that the lower pressure side (gauge pressure) is more than approx. 0.1 8 MPa (1.8 kg/cm2.G). BR
ECM
Start the engine, and short-circuit the ECM terminal No. 14 to the ground. Check the magnet clutch operation.
INTAKE AIR TEMPERATURE SENSOR
Start the engine, and short-circuit the intake air temperature sensor terminal No. 1 to the ground. Check the Rs
maanet clutch o~eration.
Blower Fan Motor System Check
BLOWER FAN MOTOR
Disconnect the blower fan motor connector. Short-circuit the blower fan motor terminals No. 2 and 5 to El!, (
the ground. Apply approx. 12V to the terminal No. 6, and check the motor operation.
Connect the blower fan motor connector. Turn the ignition switch to the ON position, and change the fan sD
switch from 1st to 4th. Check the blower fan motor terminal No. 5 with an oscilloscope. When the termi-
nal No.
5 is normal according to the following table and the fan airflow does not change, this indicates a
faulty blower fan motor.
When the terminal No.
5 results differ from the following table and the fan airflow does not change, this
indicates either a faulty harness between the blower fan motor and automatic amplifier, or a faulty auto-
matic amplifier.

FULLY AUTOMATIC AIR CONDITIONER
Blower Fan Motor System Check (Cont'd)
Terminal No. 5 (oscilloscope)
1 st speed
TI : Approx. 3.2 ms
Duty ratio: Approx. 20% 2nd
speed
3rd speed
T2: Approx. 2.2
ms
Duty ratio: Approx. 45%
T3: Approx. 1.44 ms
Duty ratio: bprox. 64%
4th speed
Duty ratio: Approx. 100%
Approx. 4 ms-Tx Duty ratio = Approx. 4 ms x 100%
BLOWER FAN RELAY
Remove the blower fan relay. Apply approx. 12V to the blower fan relay terminals No. 1 and 2. Check the
relay operation sound.
Check the continuity between terminals No.
3 and 5.
Actuator System Check
DOOR ACTUATOR MOTOR
Disconnect every door actuator connector. Check the continuity between each door actuator terminals No. 3
and 1, 3 and 2, 3 and 5, and 3 and 6.
DOOR ACTUATOR HARNESS
Check the continuity between the automatic amplifier and every actuator.
Check that there is no short-circuit between actuator driver signals. (If there is a short-circuit, the actua-
tors
will vibrate during operation.)

CENTRAL DOOR LOCK SYSTEM
Component
Parts Location
Door lock relay
LOCK -
Door lock relay
connector
1 LOCK 1
TK20 I I 5\41 1 (Brown) 1 11el j I 1
Combination meter
(Meter C/U) connector
I
Circuit Diagram
Driver door lock
Remote control entry
SW signal C/U connector
Lock signal
18. Unlock sign311 5 T 1
PMI main SW
(Central door lock SW)
----- I . RH door1
actuator 1 I I I Rear LH door I lock actuator I I I,,,,,,,------J
Driver door lock
actuator SW
P/'W main SW connector PNV main SW connector
(2-door Coupe) 1 (4-door Sedan) OCC3324 C
Combination Meter (meter control unit) Input/
Output Signal Specifications
-
I
. . 4 1 Driver door lock switch signal I
Specification
Approx. OV
Locked (OFF)
5
18
55
56
60
Operation or condition
Unlocked (ON1
Terminal No.
Approx.
5V
Signal name
Central door lock switch unlock signal
Central door lock switch lock signal
Ground Passenger and rear
RH 8 LH door lock
actuator lock signal
Passenger and rear RH & LH door lock actuator unlock siqnal Unlocked
(ON)
Operation other than above (OFF)
Locked (ON)
Operation other than above (OFF)
-
Central door lock switch is locked.
Central door lock switch is unlocked. Approx.
OV
Approx. 5V
Approx.
OV
Approx. 5V
Approx.
OV
Changes from approx. 12 to OV and back
to approx. 12V.
Changes from approx.
12 to OV and back
to approx. 12V.

CENTRAL DOOR LOCK SYSTEM
Symptom
Passenger door lock and rear
RH & LH door locks do not lock or unlock with the
central door lock switch.
Passenger door lock, rear
RH door lock,
or rear LH dooc lock do not lock or unlock
with the central door lock switch.
Passenger door lock and rear
RH & LH door locks do not lock or unlock with the
driver door lock knob. (They operate
properly with the central door lock switch.)
Inspection before Trouble Diagnoses
Check that components connectors are properly connected.
Trouble Diagnoses
SYMPTOM CHART
Malfunctioning item
Door lock relay circuit Possible
cause E8G Faulty power window main switch (central door lock switch)
Power window main switch circuit
Faulty door lock relay
Faulty door lock relay to combination meter (meter control unit)
BR harness
0 Faulty power window main switch (central door lock switch) to
combination meter (meter control unit) harness
Faulty power window main switch (central door lock switch) ground
circuit
I Faulty door lock relay to door lock actuator harness
Door lock actuator circuit
Combination meter
(meter control unit)
0 Faulty door lock actuator Faulty door lock actuator to door lock relay harness
0 Faulty combination meter (meter control unit) ST
Driver door lock switch circuit
0 Faulty driver door lock switch . Faulty driver door lock switch to combination meter (meter control
unit) harness
Combination meter (meter control unit)
Faulty driver door lock switch ground circuit
Faulty combination meter (meter control unit) m

I Sunroof motor assembly 1 Component Parts Location
I Sunroof switch < OCEM57DI
Circuit Diagram
CIB PMl relay
Sunroof motor assembly (Fully-closed position)
I I Limit SW 2 I -1 I i
3
5
1 1 -- LL
1 --
CLOSE relay - I ~irnitsw~ I
Sunroof SW
Slide SW
CLOSE 5--1
Sunroof Switch and Sunroof Motor Assembly
InputlOutput Signal Specifications
-
Measuring condition
I I
- Operation
Terminal No.
1
2
Ignition switch
3
4
5
ON
ON
'lased
ON
ON
ON Approx.
12V
OV
~~ll~ closed position to fully open position
Approx. 2V
OV
Approx. OV OV
OV
'Pen
Position
to fully closed
position
Approx.
OV (Motor is running.)
Approx. 2V
Approx. OV OV
OV
Fully closed position
to tilt UP position
Approx.
12V
Approx. OV (Motor is running.)
Approx.
OV
Tilt UP position to
fully closed position
Approx.
OV (Motor is running.)
12'
Approx. 12V
Approx.
OV (Motor is running.)
ov
OV
Approx. OV
ov
OV
Approx. OV