ECU NISSAN GT-R 1998 Service Manual

CONSULT CHECKING SYSTEM
Function and System Application
Diagnostic test mode
Work support
Self-diagnostic results
Trouble diagnostic record Function
This mode enables a technician to adjust some devices faster
and more accurately by following the indications on CONSULT.
ECU discriminated
No.
Data monitor
I I whether each system is "OK" or 'NG". lxH-1-
Conducted by CONSULT instead of a technician to determine
Function test Self-diagnostic
results can be read and erased quickly.
Current self-diagnostic results and all trouble diagnostic records
previously stored can be read.
Active test
ECM part number
L x: Applicable ENGINE
x
Classification
number of a replacement ECU can be read to pre-
vent an incorrect ECU from being installed.
InputIOutput data in the ECM can be read.
Lithium Battery Replacement
x
Diagnostic Test Mode in which CONSULT drives some actuators
apart from the
ECMs and also shifts some parameters
in a
specified range.
ECM part number can be read.
CONSULT contains a lithium battery. When replacing the battery obey the following:
WARNING:
Replace the lithium battery with SANYO Electric Co., Ltd.,
CR2032 only. Use of another battery may
present
a risk of fire or explosion. The battery may present a fire or chemical burn hazard if mistreated.
Do not recharge, disassemble or dispose of in fire.
Keep the battery out of reach of children and discard used battery conforming to the local regulations.
AfT
-
-
x
Checking Equipment
x
-
x
x
When ordering the below equipment, contact your NlSSAN distributor. Air
bag
-
-
-
x
!
Tool name ABS
-
x
X
-
x
NISSAN CONSULT
@ CONSULT unit
and accessories
@ Program card
UE990: For Automatic
transmission of
Dual
rnatic M-ATx
EE980: Except for Auto-
matic transmission
of Dual
matic
M-Atx
x
-
--
X
-
Description
-
x
-
-
x
x

TROUBLE DIAGNOSES
Self-diagnosis
(Cont'd)
SELF-DIAGNOSTIC INDICATION ITEMS
I time while the engine is running. I
MIL indication
-
DTC No.
,,
MIL lights up. l2
Self-diagnostic test items
Crankshaft position sen-
sor signal circuit Malfunction (DTC No.)
indication conditions (Malfunction is detected when ...)
lo (POS) signal or 120" (REF) signal is not input for predetermined time
while the engine is running.
Abnohal correlation is detected between 1" (POS) signal and 120" (REF)
sianal.
Mass air flow sensor
signal circuit
MIL lights up.
Engine coo'ant tempera-
"
Mass air flow sensor output voltage is 4.9V or greater for predetermined
time when ignition switch is turned from OFF to ON, or after the engine is
stalled.
Mass air flow sensor output voltage is less than 0.3V for predetermined
Engine coolant temperature sensor output voltage is approx.
4.8V or
greater (open circuit) or less than
0.06V (short circuit) for predetermined
MIL lights up.
-
14
ABS-TCS control unit
circuit JRB25DEl-l
ture sensor signal circuit Throttle control unit detects malfunction
in the system. (Open throttle sen- sor harness, etc.)
Ignition signal circuit
Turbo pressure sensor
signal circuit
[RB25DET]
Overheat
I 1 mined time. I
time-
Vehicle speed sensor
signal circuit
Motor throttle switch sig-
nal circuit
[RB25DET]
TCS/ABS control unit detects malfunction. 1 -
I Knock sensor signal cir-
cuit
- --
No vehicle speed signal is input for predetermined time while the vehicle is
being driven after warm up.
Abnormal correlation is detected between input voltages from the throttle
motor sensor and from the motor throttle switch for predetermined time.
I
MIL lights up. Heated oxygen sensor
signal circuit
Throttle position sensor
signal circuit
No consecutive ignition signal while the engine is running.
Turbo pressure sensor output voltage is approx. 4.8V or greater (open cir-
cuit) or less than
0.06V (short circuit) for predetermined time.
Engine coolant temperature sensor output voltage is approx. 0.35V or less
(sensor normal) for predetermined time.
a Heated oxygen sensor output voltage is approx. 0.2V or greater and less
than approx.
0.4V for predetermined time while the vehicle is being driven
aner warm up. Heated oxygen sensor output voltage is approx. 2V or greater for predeter-
ABS-TCS communica- tion circuit
[RB25DET]
Throttle motor sensor
signal circuit
[RB25DET]
Afr communication cir-
cuit
MIL lights up.
lights
up.
MIL lights up.
NQ malfunction
I a At least one knock sensor indicates the output voltage of approx. 4V or
greater (open circuit) or less than approx.
1V (short circuit).
Throttle position sensor output voltage is approx. 4.7V or greater (open cir-
cuit) or less than
0.06V
(short circuit) for predetermined time while ark/
a Throttle motor sensor input voltage is approx. 418~or greater (open circuit) MIL lights up.
or less than
0.3V
(short circuit) for predetermined time. I
-
MIL liqhts up. neutral position switch is OFF and vehicle speed is 4 kdh or higher.
a Malfunction (openlshort circuit, etc.) is detected in multiplex communication
line between enaine and
TCWABS.
Malfunction is detected in PA communication circuit in ECM (-TCM).
[RBZODE (UB), RB25Dm a Malfunction (open circuit, short circuit, etc.) is detected in multiplex commu-
nication line between ECM and TCM.
[RB25DE1
-
-
No malfunction is detected in all the above circuits. I - - --
Some of the above ~elfaia~nostic test items can cause related malfunctions to be detected in M,
throttle control, and ABS seif-diagnosis when malfunction is detected. Therefore, malfunctions should
also be checked in self-diagnostic tests for systems other than engine.
CONDITIONS TO TURN OFF MALFUNCTION INDICATOR LAMP
Vehicle speed sensor signal circuit: Correct the sensor signal, then drive the vehicle at 4 km/h or higher.
Overheat: Check
for causes of overheat, then erase self-diagnostic results.
Other items: Malfunction indicator lamp turns
OFF when the vehicle returned to normal condition.
HOW TO ERASE SELF-DIAGNOSTIC RESULTS
In Diagnostic Test Mode II, with the engine stopped (ignition switch ON), connect terminals "CHK" and "IGFP
on the data link connector for
2 or more seconds with a suitable harness, then disconnect them.

TROUBLE DIAGNOSES m
CONSULT (Cont'd)
SELF-DIAGNOSTIC RESULTS MODE
When any of the control unit input/output signal circuits fails and the self-diagnostic malfunction detection
conditions
are satisfied, the malfunctioning circuit is stored in the memory and displayed later.
Self-diagnostic test items I Malfunction is detected when ... Data storage
Malfunction display item I (Yes/No,
Crankshaft position sen-
sor signal circuit
I predetermined time while the engine is running. 1 1 mm
Mass air 'low sensor sig- nal circuit
1" (POS) signal or 120" (REF) signal is not input for pre-
determined time while the engine is running.
Abnormal correlation is detected between 1" (POS) sig-
nal and 120" (REF) signal.
Mass air flow sensor output voltage is 4.9V or greater for
Vehicle speed sensor sig-
No vehicle speed signal is input for predetermined time Vehicle speed sensor I I Yes ST nal
circuit I while the vehicle is beina driven after warm UD.
predetermined time when ignition switch is turned from
OFF to ON, or after the engine is stalled.
Mass air flow sensor output voltage is less than 0.3V for
Engine coolant tempera-
ture sensor signal circuit
Crankshaft position sen-
sor
Mass air flow sensor
AT
Yes RS
-.
yes I
Engine coolant temperature sensor output voltage is
approx. 4.8V or greater (open circuit) or less than 0.06V
(short circuit) for predetermined time.
switch sig- nal circuit JRB25DETI
Engine coolant tempera- ture sensor
Abnormal correlation is detected between input voltages
from the throttle motor sensor and from the motor
throttle switch for predetermined time.
ABS-TCS control unit cir- cuit [RB25DETJ
19 L~J
Yes
--
Motor throttle switch
lgnition signal circuit
Turbo pressure sensor
signal circuit [RB25DETl
Overheat
Yes
Throttle control unit detects malfunction in the system.
(Open throttle sensor harness, etc.)
TCS/ABS control unit detects malfunction.
Heated oxygen sensor signal circuit ABS-TCS
C/U SIGNAL
No consecutive ignition
signal while the engine is run-
ning.
Turbo pressure sensor output voltage is approx. 4.8V or
greater (open circuit) or less than
0.06V (short circuit) for
predetermined time.
Engine coolant temperature sensor output voltage is
approx.
0.35V or less (sensor normal) for predetermined
time.
Yes
Heated oxygen sensor output voltage is approx. 0.2V or
greater and less than approx.
0.4V for predetermined
time while the vehicle is being driven after warm up.
Heated oxygen sensor output voltage is approx. 2V or
greater for medetermined time.
Knock cuit lgnition
switch (Start sig-
nal)
TURBO PRESS SENSOR
OVER HEAT
Oxygen sensor
Yes Yes
EL
Yes
8D
Yes
At
least one knock sensor indicates the output voltage of
approx. 4V or greater (open circuit) or less than approx.
1 V (short circuit).
Throttle position sensor
signal circuit
ABS-TCS communication
Malfunction (openlshort circuit, etc.) is detected in multi- ABSrrCS C,u circuit [RB25DETl 1 plex communication line between enaine and TCS/ABS. I
Knock sensor
Throttle position sensor output voltage is approx. 4.7V or
greater (open circuit) or
0.06V or less (short circuit) for
predetermined time while
parkheutral position switch is
OFF and vehicle
s~eed is 4
km/h or hiaher. Thronle
position sensor
Throttle motor sensor sig- nal circuit
[RB25DET] Yes
AiT communication
circuit
Yes
Throttle motor sensor input voltage is approx. 4.8V or
greater (open circuit) or less than
0.3V or less (short cir-
cuitl for
redetermined time.
No malfunction Motor
throttle sensor
Malfunction is detected in A/T communication circuit in
ECM
(.TCM).
(RB2ODE
(UB), RB25DET]
a Malfunction (opedshort circuit, etc.) is detected in multi-
plex communication line between ECM and TCM.
[RB25DE1
No malfunction is detected in all the above circuits.
A/T COMM LINE
NO SELF DIAGNOSTIC
FAILURE INDICATED.
FURTHER TESTING MAY
BE REQUIRED.
Some of the above self-diagnostic test items can cause related malfunctions to be detected in An;
throttle control, and ABS self-diagnosis when malfunction is detected. Therefore, malfunctions should
also
be checked in self-diagnostic tests for systems other than engine.

TROUBLE DIAGNOSES
CONSULT (Cont'd)
DATA MONITOR MODE (M)
1 I Monitor item
I
tem Display ECU
input Main
signals
-
Description Remarks
signals
VHCUS
SE.A'T
[kmlh] or [mph]
I-
Vehicle speed computed from When
racing engine in "Nn or "P" signal of revolution sensor is position
with vehicle stationary,
displayed. CONSULT
data may not indicate
0 kmlh (0 mph).
Vehicle speed computed from Vehicle
speed display may not be
signal of vehicle speed sensor accurate under approx. 10 kmlh
is displayed. (6 mph). It may not indicate 0
kmlh (0 mph) when vehicle is sta-
tionary.
Throttle position sensor signal
voltage is displayed.
AlT fluid temperature sensor
signal voltage is displayed.
Signal voltage lowers as fluid
temperature rises.
Source voltage of TCM is dis-
played.
Engine speed, computed from Engine speed display
may not be
engine speed signal, is
dis- accurate under approx. 800 rpm.
played. It
may not indicate
0 rpm even
when engine is not running.
Turbine revolution computed Error
may occur under approx.
from signal of turbine revolution 800 rpm and will not indicate
0
sensor is displayed. rpm even if engine is not running.
ONIOFF state computed from
signal of overdrive control SW
is displayed.
ONIOFF state computed from
signal of PIN position SW is
displayed.
ONIOFF state computed from
signal of
R position SW is dis-
played.
ONIOFF state computed from
signal of D position SW is dis-
played.
ONIOFF status, computed from
signal of 2 position SW, is dis-
played.
signal of
1 position SW, is dis-
displayed. ASCD is mounted.
ON
... Cruising state
OFF ... Normal running state
Vehicle
speed sensor
1 (All) (Revolution sensor)
Vehicle speed sensor
2 (Meter) VHCUS SE,MTR
[kmk] or
[rnph]
Throttle position sensor
ITHRTLPOS SEN
I ,
AT fluid temperature sensor
PI
FLUID TEMP SE
Battery voltage
A
Engine speed ENGINE SPEED
[rpml
Turbine revolution sensor
TURBINE REV
[rpml
I
Overdrive control switch
OVERDRIVE SW
[ONIOFFJ
I
PIN position switch
PIN POSI SW
[ONlOFF]
R position switch
R POSITION SW
[OWOFF]
I
2 position switch
1
2 POSITION SW
[ONIOFF]
I
D position switch
1 position switch 1 POSITION SW
[ONIOFF]
I
D POSITION SW
[ON/OFF] X
ASCD OD cut signal
ASCD.OD CUT
[ONIOFF]
X
ASCD cruise signal
Status of ASCD OD release
signal is displayed.
ON
... OD released
OFF ... OD not released
ONIOFF status, computed from
signal of
kickdown SW, is dis-
played.
ONIOFF status, computed from
signal of HOLD shift SW, is dis-
played.
ONIOFF status, computed from
signal of closed throttle position
SW, is displayed.
ONIOFF status, computed from
signal of wide open throttle
position SW, is displayed.
ASCD.CRUISE
[ONIOFF]
This
is displayed even when no
ASCD is mounted.
This is displayed even when no
kickdown switch is equipped.
Kickdown
switch
KICKDOWN
SW
[ONIOFq
Wide open throttle position switch X .
X A/T mode switch
t
WIO THRUP-SW
[ONIOFq POWERSHIFT SW
[ONIOFF]
Closed
throttle position switch
, CLOSED THUSW
[ONIOFF]

ANTI-LOCK BRAKE SYSTEM
CONSULT (Cont'd)
I b~ SELECT DiAG MODE 01 r SELF-DIAG RESULTS
DATA MONITOR
ACTIVE TEST
ECU
PART NUMBER I
FR RH SOL TEST
I 1 !!! SELECT MONITOR ITEM I I
I I SELECTION FROM MENU I I
I I START 1
6. Touch "ACTIVE TEST'.
7. Select active test item by touching screen.
8. Touch "START'.
9. "ACTIVE TEST" screen is displayed.
ABS solenoid valve
To check that ABS solenoid valves (inlet and outlet) operate in
the following manner, touch
"UP*, "KEEP" and "DOWN" on the
screen while observing the monitor.
Operation I UP I KEEP ( DOWN
IN ABS SN I OFF 1 ON I ON
OUTABS SN I OFF I OFF I ON*
*: Solenoid valve stays ON for 1 to 2 seconds after touching the key, and then
turns OFF.
If the active test is conducted with brake pedal depressed, the
brake pedal travel limit may change. This is a normal condition.
"TEST IS STOPPED" message is displayed 10 seconds after
the operation is started.
If the active test needs to be performed again after "TEST IS
STOPPED" is displayed, repeat step 8.

TCS/ABS SYSTEM
CONSULT for TCS/ABS Control Unit Control
CONSULT
START I
I I BR455D I SUB MODE
I SELECT SYSTEM
ENGINE
Arr
1 ABS I
I
[ $ SELECT DlAG MODE 01
SELF-DIAG RESULTS
DATA MONITOR
ACTIVE TEST
ECU
PART NUMBER
FR RH SOL TEST I
$ SELECT MONITOR ITEM
SELECTION FROM
MENU
u
START
System (Cont'd)
ACTIVE TEST PROCEDURE
When conducting Active test, vehicle must be stationary.
Confirm that brakes have been bled completely.
When ABS warning
lamp stays on, never conduct Active test.
Turn ignition switch OFF.
Connect CONSULT to Data Link Connector for CONSULT.
Start engine.
Touch "START' on CONSULT screen.
Touch
"ABS".
Touch "ACTIVE TEST'.
Select active test item by touching screen.
Touch "START'.

TCSIABS SYSTEM
CONSULT
for Throttle Control Unit Control
bJ SELECT DIAG MODE
SELF-DIAG RESULTS & I
DATA MONITOR 1
ACTIVE TEST I
ECU PART NUMBER I
I P?j SELECTTEST ITEM
I THROTIIEZ OPENING a
I THROTTLE MOTOR I
1 THROTLE MOTOR RLY 1
w ACTIVE TEST
THRTL2 OPENlNG 0.00" ---------- ---------- MONITOR ==========
THRL2 OPENING 0.00"
THMOTORDUTY 20.0°/0
System (Cont'd)
Touch "ACTIVE TEST".
Touch
"MOTOR THROSTLE OPEN" on the "SELECT TEST
ITEMn screen.
Touch "START' with "MAIN SIGNALS" reversed.
Set the motor throttle target angle to
0° (fully closed).
The motor throttle target angle shown on the screen is 2".
After the steps above, confirm that the engine speed is limited
when the acceleration pedal is depressed.
As shown above, change the motor throttle angle several times
while observing the limitation of the engine speed in accor-
dance with the throttle angle.

FULLY AUTOMATIC AIR CONDITIONER
Trouble Diagnosis
by Gauge Pressure
Connect the manifold gauge to the cooler cycle (service valve). Speculate and correct the root cause and
trouble location based on the cooler cycle pressure.
Probable cause
lnsufficient cooling
by con-
denser
Radiator fan malfunction
lmproper air guard attach-
ment
Clogged or dirty condenser
fins Corrective action
Symptom Cycle status
Repair or replace faulty parts.
Clean or repair the condenser
Pressure retums to normal
when water is splashed on the
condenser. fins.
Both high- and low-pressures
are high.
Recover all refrigerant. Re-
vacuum and charge to appro-
priate amount.
Refrigerant
over-charge
When the compressor is
stopped, the pressure drops
suddenly approx.
2 kg/cm2.
Then, the pressure drops
gradually. Recover
all refrigerant. Re-
vacuum and charge to appro-
priate amount.
Air is mixed
in the cooler cycle.
High-pressure is too high.
Temperature differences occurs
where the high-pressure pipe is
crushed or clogged. Crushed
or clogged high-pres-
sure pipe between the com-
pressor and condenser
High-pressure
is high, and
low-
pressure is too low. Repair or replace
faulty part.
Evaporator outlet is not cooled. Clogged
expansion valve
Gas leak at temperature sen-
sor
Clogging due to foreign mat-
ter
There
is a temperature differ-
ence at the liquid tank outlet
pipe, or liquid tank is covered
with frost. Remove
foreign matter in
expansion valve, or replace.
Liquid tank malfunction
(clogged strainer) Replace
liquid tank.
Both high- and low-pressures
are low. (Sometimes the low
pressure is negative.)
lmproper attachment or failure
of intake air temperature sen-
sor thermistor Replace
intake air temperature
sensor, or repair
thermistor
attachment position.
Evaporator
outlet pipe is cov-
ered with frost (no airflow).
I Inspect for refrigerant leakage.
There is some temperature dif-
ference between compressor
high- and low-pressure pipes. Recover
all refrigerant.
Re-
lnsufficient refrigerant vacuum and charge to appro-
priate amount.
Extract all refrigerant. Suff
i-
ciently vacuum and remove
moisture. Charge to appropri-
ate amount. At this time,
replace the liquid tank without
fail.
Sometimes, the evaporator out-
let is not cooled. Sometimes,
the evaporative inlet is covered
with frost. Moisture
is mixed in the cooler
cycle. (Clogging due to frozen
moisture in the expansion
valve)
Sometimes
high-pressure is
low, and low-pressure is nega-
tive.
When the compressor is
stopped, the pressures equal-
ize. There is no temperature
difference between the com-
pressor high-pressure pipe and
low-pressure pipe. Compressor
malfunction
(com-
I
pression defect)
Valve damage or failure
Faulty gasket Replace
the compressor.
High-pressure
is low, and
low-
pressure
is high.
HA-I 0

METER
Combination Meter (Cont'd)
Installation
1. Push the flexible print circuit into the connector and press it
down with the connector.
2. Verify that the flexible print circuit is securely connected with
the connector.
3. Check that there is continuity between the connector connect-
ing check terminals.
BEHIND COMBINATION METER AND INTERNAL
CIRCUIT
1 27 (Ground)
2 x
z g2
15 55 13 (Ground)
1 51 (Ground)
5 1 Ground) z I (Ground!
Bulb color: G: Green L: Blue R: Red Y: Yellow
51 27 (Ground)
(Ground)