1998 NISSAN GT-R diagram

HOW TO USE THIS MANUAL
b This Service Manual only contains the service data specifications and trouble diagnosis informa-
tion such as self-diagnosis,
CONSULT, circuit diagram and so on.
b For other information not specified in this manual, refer to Japanese version Service Manual (Pub.
No. A006029) and wiring diagram manual (Pub. No.
WD8EOR34JO).
IMPORTANT SAFETY NOTICE
The proper performance of service is essential for both the safety of the technician and the efficient
functioning of the vehicle.
The service methods in this Service Manual are described in such a manner that the service may be
performed safely and accurately.
Service varies with the procedures used, the skills of the technician and the tools and parts available.
Accordingly, anyone using service procedures,
took or parts which are not specifically recommended
by
NISSAN must first be completely satisfied that neither personal safety nor the vehicle's safety will
be jeopardized by the service method selected.

ENGINE CONTROL SYSTEM
SECTION EC
CONTENTS
ENGINE AND EMISSION CONTROL OVERALL
SYSTEM..
....................................................................... \
..2
System Description ...................................................... 2
Description of Engine Control ...................................... 2
System Diagram
.......................................................... 3
Component Parts Location .......................................... 6
Vacuum Hose Drawing ................................................ 8
Circuit Diagram
........................................................ 11
.................................... ECM (.EM) Terminal Layout 13
TROUBLE DIAGNOSES ............................................... 15
Fail-safe and Backup Functions 15 RS ...............................
Self-diagnosis .......................................................... 16
CONSULT .................................................................. I9 MA ............................................... Symptom Matrix Chart 28
Idle Speed Inspection and Adjustment
..................... ;35
................ Ignition Timing Inspection and Adjustment 36
AirIFuel Ratio Inspection ........................................... 37
Fuel Pressure Inspection ........................................... 38
ECM (.TCM) InpuVOutput Signal Reference 9D
........................................................................\
. Value .39

ENGINE AND EMISSION CONTROL OVERALL SYSTEM
RB20DE (UB)
System Diagram
c !! I-
a
5 a - w 2 LL
Malfunction indicator lamp
-!
Fuel pump control signal
Parwneutral position switch signal
C
Vehicle speed signal - - 5 Vehicle speed signal -

ENGINE AND EMISSION CONTROL OVERALL SYSTEM
System
Diagram (Cont'd)
a
E a - al 1 U.
Malfunction indicator lamp
Fuel pump control signal
+
ParWneutral position switch signal 2 - 1 F
Vehicle speed signal D 4 -
Crankshaft position sensor signal - - - m 2 c 0, Air conditioner switch signal * Y .- "Y
~ngine coolant temperature sensor signal - B * 4 C C Ignition timing control signal 0, P - ID - - Auxiliary air control signal a C - 2s
Refrigerant pressure sensor signal +
Power steering oil pressure switch signal
Variable valve timing control sign
- Variable air intake control
I I
solenoid valve control sig

ENGINE AND EMISSION CONTROL OVERALL SYSTEM
System Diagram (Cont'd)
Resistor a
I I~I I 1
w
C LLOE Malfunction indicator lamo
I Fuel DU~D control sional I Vehicle soeed sianal I
Parklneutral position switch signan I Refrigerant pressure sensor sianal
Air conditioner switch signal- rr -
- Power steering oil pressure switch signal
Crankshaft position sensor signal s - 0 Heated oxygen sensor output signal
Engine coolant temperature sensor signalC k - Mass air flow sensor signal r
- Ignition timing control signal ,- U I W Knock sensor output signal
Airlfuel
ratio control
signal-
Variable valve
timing
control
s~anal
Turbo pressure signal
Auxiliarv
air amount control
I
signal 2 L
g E8z E $, r
Air regulator
LT Turbo pressure sensor

ENGINE AND EMISSION CONTROL OVERALL SYSTEM
Circuit Diagram
RB20DE (UB).MTT, RB25DE, RB25DET.MTT MODELS
Fan motor
Auxtliary
electric
Ian
relay
-
Alr cmdll~oner compressor
Arr
conduoner
relay
14
Y Mallunct~on indcator lamp A 17
26 $7 = Power steenng 011
pressure sw~icr.
I
23
43 Engine Want
temwrature sensor B.
Tachometer drive signal Check connmr
To rear defogger relay
/ [RB2MWD TO starter motor *'""L'*" - > TO PNP switch
I TO Starter relay
[Except lor ' - RB25DE.4WDI

ENGINE AND EMISSION CONTROL OVERALL SYSTEM
Circuit Diagram (Cont'd)
RB2ODE (UB).A/T, RB25DET.AfT MODELS
".--- , - TC rear de'ogger relay 4 49
T 176
. . .- . . . . . , ,. - . . . , 59 . : . Turbine
at -.. A sensor A
Overrun clutzh
. shdt ~lenwd valve k pressure detection switch
I' Sh:H control unit Droppins revstor 8 18 9 'S 10

AUTOMATIC TRANSMISSION
SECTION
AT
CONTENTS
SHIFT LOCK SYSTEM .................................................... 2
Component Parts Location .......................................... 2
Shift Lock Circuit Diagram ........................................... 2
Reverse Buzzer Circuit Diagram ................................. 2
TROUBLE DIAGNOSES ................................................. 3
System Description .................................................... ..3
Fail-safe Function ...................................................... ..3
................... Shift Mechanism ............. .........,,.............. .5
Clutch and Band Chart ................................................ 6
Component Parts Location .......................................... 7
........................................................... Circuit Diagram .8
Control Unit Input/Output Signal Specifications ....... .I0
Shift Pattern .............................................................. 1 3
............................................................ Shift Schedule 15
....................................................... Basic Inspection. -16
Line Pressure Test ..................................................... 16
................................................................... Stall Test 17
.................................................................. CONSULT 9
.......................................................... Self-diagnosis ..23
Symptom Chart. ........................................................ -25