1998 NISSAN GT-R fuel pressure

ENGINE AND EMISSION CONTROL OVERALL SYSTEM
Vacuum
Hose Drawing (Cont'd)
Canister purge control vzlve
1. lntake manifold collector to Recirculation valve
2. One-way valve to lntake manifold collector
3. Canister purge control valve to One-way valve
4. Canister purge control valve to Vacuum pipe
5. Turbo pressure sensor to Vacuum tank
6. Turbo pressure control solenoid valve.to Air tube
7. Turbo pressure control solenoid valve to Three-way
connector
8. Air inlet tube to Three-way connector
9. Swing valve controller to Three-way connector Canister
to Vacuum pipe
Pressure regulator to lntake manifold collector
Fuel damper to lntake manifold collector
lntake manifold collector to Vacuum pipe
Vacuum pipe to Vacuum pipe
Power steering air valve to Vacuum pipe
Power steering air valve to Air inlet hose
Air inlet pipe to Vacuum tank

ENGINE AND EMISSION CONTROL OVERALL SYSTEM
ECM (-TCM) Terminal Layout
I GY
CH~'GN- (Data link connector for CONSULT)
Terminal NO.
1 Description Terminal 1 No I Description - - 1 I lgnition
signal (Power transistor drrve signal) Cyl. No. 1 1 '34 Iu1" positron switch signal -- ---- 2 1 Ignition signal (Power transistor drive signal) Cyl. No. 5 1 '35 1 ''2" posifion switch signal - - 3 1 Ignition signal (Power transistor drive signal) Cyl. No. 3 1 36 1 -
4 I ECM 6 IGN coil relay control signal 1 37 1 Throttle opening signal
[RB25DE.4WD,M/TS RB25DE.m RB25DEll
- - - -- - - - - 8 ( Ignition signal (Power transistor drive signal) Cyl. No. 2 ( '41 1 f-k swltch signal
5
6
7
11 ( AAC valve control signal ( 44 1 Crankshaft position sensor 120' (REF) signal
Tachometer
drive signal
-
Ignition signal (Power transistor drive signal) Cyl. No. 6
9
10
'38
39
'40
Ignition signal (Power transistor drive signal)
Cyl.
No. 4
-
12
13
"D" position switch signal
Neutral signal
(Parklneutral position switch)
"R" position switch signal
14
Symbols in ( ) next to terminal numbers indicate the data link connector terminals. Items marked with are available on RB20DE (UB) and RB25DET.m models only.
42
43
-
Fuel pump relay control signal
15
16
17
18
19
20 21
22 (CHK)
23
24 (IGN)
25
26
27
28
29
30
31
32
'33
- -
Sensor around
Air conditioner relay control signal 45
46
-
-
Malfunction indicator lamp
-
-
Ignition switch (START) signal
Air conditioner switch signal
Check (Diagnosis start)
Throttle position sensor signal
Ignition switch
(IGN) signal
Control unit ground
Power steering oil pressure switch signal
-
1 SB (select bit) 1 signal [RB25DET.A/Tl
1 Vehicle speed sensor signal (Vehicle speed sensor 2)
Headlamp switch signal
Ignition power supply
Control unit ground
Idle position switch signal Crankshaft
position sensor 120" (REF) signal
Crankshaft position sensor 1
" (POS) signal
47 Ring gear crankshaft position sensor signal [RB20DE (UB)]
Turbo pressure sensor signal
LRB25DEl-J
48
49
50
51
52
53
54
55
56
57
'58 59
'60 61
62
63
64
65
66 Power
supply for throttle position sensor, refrigerant pressure
sensor, and turbo pressure sensor
Rear defogger switch signal
Heated oxygen sensor signal
Throttle motor sensor signal [RB25DET]
SB
(select bit)
2 signal (RB25DET.ATJ
Motor throttle switch signal
[RB25DET]
Mass air flow sensor signal
Mass air flow sensor ground
Engine coolant temperature sensor signal
Refrigerant pressure sensor signal
Output shaft rotation sensor signal (Vehicle speed sensor 1)
Turbine sensor signal
[RB25DET.AlTj
Oil temperature sensor signal
Knock sensor signal
1
Knock sensor signal 2
PJT mode switch signal (POWER) [RB20DE (UB).A/Tl
DB (data bush) 1 signal [RB25DET.W
DB (data bush)
3 signal [RB25DET.W

ENGINE AND EMISSION CONTROL OVERALL SYSTEM
ECM (-TCM) Terminal Layout (Cont'd)
Terminal
No.
67
'68
69 Description
70
'71
72 I
Control unit power supply
O/D OFF indicator
lamp
DB (data bush) 2 signal
[RB25DET.AIT]
73
101
104
1 [RB~ODE (LIB), BR25DEl -
Turbo oressure control solenoid valve control signal I I16 I lnjector ground
Terminal
No.
AK mode switch signal (SNOW) [RB20DE (UB).AIT]
Stop lamp switch signal
Control unit power
102
103 Description
74
75 (RX)
76
(TX)
1 I . .
-
Receive (Data input to control unit)
Transmit (Data output from control unit)
77
78
79
-
Injector No. 3 cylinder drive signal
Variable air intake control solenoid valve control
sianal
105
'106
107
-
Auxiliary electric fan relay control signal [RB25DE, RB25DElJ
ECM.TCM. TCSIABS integrated control signal [Multiplex
com-
munication] [RB25DENT. RB25DEl
Battery power supply
Line pressure solenoid valve control signal (Dropping resistor
circuit)
-
lnjector No. 1 cylinder drive signal
1 08
log
80
"I3
114
'1 15
[RB~~DET]
Injector No. 2 cylinder drive signal
Line pressure solenoid valve control signal
Air jet swirl control solenoid valve control signal
[RB20DE
(U ,\I
110 111
112 Injector No.
4 cylinder
drive signal
Overrun clutch solenoid valve control signal
"11
Canister purge control valve control signal
Control unit power supply (Counter-electromotive current
feedback
circuit) 11
7
118
.119
Symbols
in ( ) next to terminal numbers indicate the data link connector terminals. Items marked with ' are available on RB20DE (UB) and R825DET.All models only.
Injector No. 5 cylinder drive signal
Fuel pump terminal voltage control output signal
[RB25DET]
Injector No. 6 cylinder drive signal Variable
timing control solenoid valve control signal
Heated oxygen sensor heater control signal
Power indicator lamp
'120
'121 Lockup solenoid valve control signal
Shift solenoid valve
A control signal I '122
123 124 Shift solenoid valve B control signal
-
Injector ground

TROUBLE DIAGNOSES --- - - - -- -- - -
Fail-safe and Backup Functions
0 The fail-safe function estimates the opening conditions with other input signals and selects safer condi-
tions for the engine (vehicle) control, based on the data previously stored in the control unit, when any of
the critical sensors in the
ECM fails.
The backup function allows the vehicle to be driven, using control signals previously stored in the control G]
unit, even if the critical part of the system fails.
MIL indication
I
Related
sensor
Function
Backup Malfunction
Fail-safehacku p
Fixes the ignition timing, fuel injection pulse width, and
AAC valve opening to the preset values so that the vehicle
can be driven.
ECM
(-TCM)
Mass air
flow
sensor
Engine
coolant
tempera- ture sen-
sor The
microcomputer in the control
unit (CPU) is malfunctioning. MIL lights
up. A'
-- --
Selects the fuel injection pulse width according to the
engine speed and the throttle opening so that the vehicle
can be driven. Fuel injection will be inhibited when the
engine speed exceeded approx.
2,400 rpm. During fail-safe
control, idle speed is controlled to 800
rpm.
Uses the estimated engine coolant temperature (varies with
elapsed time after start) to perform controls so that the
vehicle can be driven normally. The auxiliary electric fan
relay is turned ON. On
RB25DET
model, the turbo pres-
sure control solenoid valve remains OFF.
%R
MIL lights up.
ST
Output voltage dropped below
0.3V while the engine is running.
MIL lights up.
R8 Same as self-diagnostic malfunc-
tion detection conditions.
Heated
owen
sensor Heated oxygen sensor output
voltage exceeded approx.
2V for
predetermined time.
Same as self-diagnostic malfunc-
tion detection conditions. MIL
lights up. d d Inhibits aidfuel ratio feedback control.
Judges the vehicle as of regular specification. Retards the
ignition timing within the knocking range so that the vehicle
can be driven normally.
Determines idle position according to the throttle position
and the engine speed.
Fixes the output to the preset value so that the vehicle can
be driven normally.
On
RB25DET model, the turbo pressure control solenoid
valve remains OFF.
Fail-safe
function Knock
sensor
Throttle position
sensor Same
as self-diagnostic malfunc-
tion detection conditions. MIL
lights up.
Throttle motor
sensor
--
Fixes the throttle motor sensor output to the preset value
by turning the TCS switch
ONIOFF, so that the vehicle can
Same
as self-diagnostic malfunc-
tion detection conditions. MIL
lights up.
be driven normally.
Motor
throttle
switch Same
as
self-diag
nostic
malfunc-
tion detection conditions. Fixes the
TCS switch OFF.
t.. -

TROUBLE DIAGNOSES
Self-diagnosis (Cont'd)
I Malfunction indicator lamp
MALFUNCTiON INDICATOR LAMP (MIL) INDICATION
Diagnostic test mode I - BULB CHECK
0 The malfunction indicator lamp bulb check is carried out when
the ignition switch is turned
ON (engine not started).
The malfunction indicator lamp should come ON when the
ignition switch is turned
ON, and go OFF when the engine is
started.
Example: Blinking pattern for DTC "43"
ONh
OFF
Approx. 8.7 S
OFF (Rich)
Duty ratio in 1 cycle 1 Lean: Al(A + B) x 100 Rich: B/(A + B) x 100
EFJ0041 C
Diagnostic test mode I - MALFUNCTION WARNING
The system goes into the malfunction warning mode when any of
the following conditions is satisfied, and warns the driver by light-
ing up the malfunction indicator lamp in the combination meter.
Microcomputer in the ECM control unit (CPU) is malfunction-
1
ing.
Malfunction is detected during mass airflow sensor circuit self-
diagnosis.
Malfunction is detected during engine coolant temperature
sensor circuit self-diagnosis.
Malfunction is detected during vehicle speed sensor circuit
self-diagnosis.
Malfunction is detected during ignition signal circuit
self-diag-
nosis.
Malfunction is detected during overheat self-diagnosis.
Malfunction is detected during heated oxygen sensor circuit
self-diagnosis.
~alfunsion is detected during throttle position sensor circuit
self-diagnosis.
Malfunction is detected during Turbo pressure sensor circuit
self-diagnosis.
[RB25DET model]
Malfunction is detected during throttle motor sensor circuit self-
diagnosis.
[RB25DET model]
Diagnostic test mode I1 - SELF-DIAGNOSTIC RESULTS
0 This mode indicates the malfunctioning system(s) by the mal-
function indicator lamp blinking pattern (indicating the DTC).
0 When no malfunction is detected, DTC "55" is indicated.
Diagnostic test mode II - HEATED OXYGEN SENSOR
MONITOR
0 This mode indicates status of the aidfuel ratio by blinks of the
malfunction indicator lamp.
Warm up the engine and increase and maintain the engine
speed at 2,000 rpm. Check that the malfunction indicator lamp
blinks at least five times in
10 seconds.
During airlfuel ratio feedback control,
when heated oxygen sensor output is high (rich): MIL goes
OFF.
when heated oxygen sensor output is low (lean):
MIL comes
ON.
When aidfuel ratio feedback control is clamped: Status just
before clamp
is maintained.
When airifuel ratio feedback control is stopped: MIL goes OFF.

TROUBLE DIAGNOSES
CONSULT (Cont'd)
FUNCTION
Self-diagnostic results Diagnostic test mode
Work support
Self-diagnostic resuits can
be read and
erased quickly. Function
A technician can adjust some devices faster
and more accurately by following indications
on CONSULT.
Data monitor
Active test
WORK SUPPORT MODE
Input/Output data in the ECM can be read.
CONSULT drives some actuators apart from
the
ECM's and
also shifts some parameters in
a specified range.
Conducted
by CONSULT instead of a techni-
Function test
ECM part number
WORK ITEM I CONDITION I USAGE
cian to determine whether each system is
"OK" or
"NG".
ECM part number can be read.
THRTL
POS SEN ADJ CHECK THE THROTTLE POSITION SENSOR SIGNAL.
ADJUST IT TO THE SPECIFIED VALUE
BY ROTATING
THE SENSOR BODY UNDER THE FOLLOWING CONDI-
TIONS.
0 IGN SW "ONn
0 ENG NOT RUNNING When adjusting
throttle position
sensor initial position
I ACC PEDAL NOT PRESSED 1 I
IACV-AAC VALVE ADJ I SET ENGINE SPEED AT THE SPECIFIED VALUE UNDER I 1 THE FOLLOWING CONDITIONS.
ENGINE WARMED UP
When releasing fuel pressure I
from fuel line
FUEL
PRESSURE RELEASE
0 NO-LOAD
FUEL PUMP WILL STOP BY TOUCHING "START"
DURING IDLING.
CRANK A FEW TIMES AFTER ENGINE STALLS.
i J

TROUBLE DIAGNOSES
CONSULT (Cont'd)
DATA MONITOR MODE
ECM input
signals
Monitored item
[Unit] Main
signals Remarks
Description
lndicates the engine speed computed
from the POS signal (lo signal) of the
camshaft position sensor.
When the engine is stopped, a certain
value is indicated.
When the engine coolant temperature
sensor is open or short-circuited, ECM
enters fail-safe mode. The engine coolant
temperature determined by the ECM is
displayed.
The signai voltage of the mass air flow
0 sensor is displayed.
The engine coolant temperature (deter-
mined by the signal voltage of the engine
0 coolant temperature sensor) is displayed.
-
MAS AIRiFL SE [V]
The signal voltage of the oxygen sensor
is displayed.
02
SEN [V]'
0 After turning ON the ignition switch, "RICH" is displayed until air-fuel mixture
ratio feedback control begins.
When the air-fuel ratio feedback is
clamped, the value just before the clamp-
ing is displayed continuously.
MiR
F/C MNT*
[RICH/LEAN] Display of oxygen sensor signal during
air-fuel ratio feedback control:
RICH
... means the mixture became
"rich", and control is being affected
toward a leaner mixture.
LEAN
... means the mixture became
"lean", and control is being affected
toward
a rich mixture.
The vehicle speed computed from the
vehicle speed sensor signal is displayed. VHCL SPEED SE [krn/h] or [mph]
The power supply voltage of ECM is dis-
played. I BATTERY VOLT [V]
THRTL POS SEN [V] The throttle position sensor signal volt-
age is displayed.
Throttle motor sensor output voltage Approx. 4.6V THRTL POS SE2 [V] 0 RB25DET
TURBO BOOST
SENSOR
RB25DET
Turbo pressure sensor output voltage 0 Approx. 2.7V
Indicates [ON/OFF] condition from the After starting the engine, [OFF] is dis-
0 starter signal. played regardless of the starter signal.
lndicates [ON/OFF] condition from the 0 throttle position sensor signal.
-
START SIGNAL
[ON/OFF]
CLSD THUP SW
[0
N/O
FF]
0 lndicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner sianal. AIR COND SIG
[ON/OFF]
lndicates [ON/OFFj condition from the
parldneutral position switch signal.
PiN
POSl SW [ONIOFF)
PW/ST SIGNAL
[ONIOFF]
LOAD SIGNAL
[ON/OFF]
lndicates [ON/OFfl condition from the
electrical load signal
andlor lighting
switch.
ON ... rear defogger is operating.
OFF ... rear defogger is not operating.
NOTE: Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically. *: Models with three way catalyst.

TROUBLE DIAGNOSES .
CONSULT (Cont'd)
Monitored item
[Unit] signals Description
Remarks
INJ
PULSE [msec]
I
When the engine is stopped, a certain
computed value is indicated. lndicates the actual fuel injection pulse
width compensated by ECM according to
the input
siqnals.
IGN TIMING [BTDC]
I lo
lndicates the ignition timing computed by ECM according to the input signals. When the engine is stopped, a certain
value is indicated.
IACV-AACN
I%]
I lo
lndicates IACV-AACN control value com-
puted by ECM according to the input sig-
nals.
PURG VOL CN
[ONIOFF dutyj lndicates the EVAP canister purge vol-
ume control valve computed by the ECM according to the input signals. The opening becomes larger as the
value increases.
AIF
ALPHA [%]
- The mean value of the air-fuel ratio feed-
back correction factor per cycle is indi-
cated. -- - When the engine is stopped, a certain
value is indicated.
This data also includes the data for the
air-fuel ratio learning control.
AIR COND
RLY [ONIOFF] The air conditioner relay control condition
(determined by ECM according to the
input signal) is indicated.
-- - - Indicates the fuel pump relay control con-
dition determined by ECM according to
the input signals.
The control condition of the intake valve
timing control solenoid valve is indicated.
ON
... Intake valve timing control is oper-
ating. OFF
... lntake valve timing control is not
operating.
VlAS
SN [ONIOFF] RB20DE (UB), RB25DE
Control conditions computed by ECM Solenoid valve activated: ON Solenoid valve not activated: OFF
SWRL CONT SN
[ON/OFF]
0 RB20DE (UB)
COOLING FAN
[HVLOW/O FF] RB25DE, RB25DET
The control condition of the cooling fan
(determined by ECM according to the
input signal) is indicated.
HI
... High speed operation LOW ... Low speed operation
OFF ... Stop
TURBO CONT
SN 0 RB25DET Control conditions computed by ECM
Solenoid valve activated: ON Solenoid valve not activated: OFF
PD PRESSURE
SENSOR M Refrigerant pressure sensor output volt-
age Approx. 0.36V min.
(Varies with air conditioner refrigerant
pressure)
, VOLTAGE Voltage measured by the voltage probe.
Pulse width, frequency or duty cycle
measured by the pulse probe. Only "#" is displayed if item is unable to
be measured.
r Figures with "#"s are temporary ones.
They are the same figures as an actual
piece of data which was just previously
measured.