1998 NISSAN GT-R brake fluid

TROUBLE DIAGNOSES
Symptom Matrix Chart (Cont'd)
Engine mechanical-related malfunction I Symptom characteristics and inspection hints
Airffuel
ratio becomes lean.
Air sucked in at oil filler cap
Aidfuel ratio compensation factor becomes higher.
a Intake manifold induction vacuum becomes lower.
I Cracked intake manifold I
Misconnection of canister piping Use an induction vacuum (pressure) gauge for check.
' Common to all air sucking conditions from air intake system.
-
PCV valve stuck open
I Malfunctioning pressure regulator I Various symptoms occur depending on the fuel pressure.
Abnormal noise (peep) may
be heard.
Air/fuel
mixture
Improper gasoline properties Various
symptoms occur depending on the properties.
IEGRiale
stuck open
I
Clogged fuel strainer .
Clogged air cleaner element
Deposits on valve
r
Symptoms vary with the condition how they are clogged. However, the
symptoms tend to occur when the vehicle is driving at high speed and
under high load.
I
Air/fuel ratio becomes lean. Airfluel ratio compensation factor becomes
higher.
Excessive canister purge volume
I
Engine may stall when the accelerator pedal is lightly pressed. (Especially
in summertime.)
Misconnection of high-tension wire Check if the ignition timing
is correct. 1 Improperly adjusted ignition timing 1
Malfunctioning spark plug 1
Corn- I Improper valve contact I Symptoms vary with the degree of contact and the number of cylinders. '
High-tension wire leaks
Distributor
cap leaks Symptoms
vary with the degree of leaks.
Clogged catalytic converter or exhaust sys-
l tem , In many cases, engine stalls and then restarts after a while. I
pression I
Low base idle speed
pressure
Worn piston ring I
Engine may
stall while the vehicle is decelerating or when the power '
steering load or electrical load is applied.
Symptoms vary
with the degree of wear and the number of cylinders.
I
Air conditioner load too heavy I Too much refrigerant in the system. j
Others Dragging
brake
Belt tension too high
1
I Clogged radiator or capacitor I
ArJ load too heavy
Foreign material (vinyl, etc.) in fuel tank Insufficient A/T fluid (FR model)
Symptom tends to occur when fuel level in the tank becomes lower.

TROUBLE DIAGNOSES
Control Unit
InputlOutput Signal Specifications
Terminal
No.' Operation
or measurement condition Specifications
Idle switch
(in throttle position switch) After
engine warm-up, release accelerator pedal.
After engine warm-up, depress accelerator
pedal.
PNP switch "1"
position
(c > is used for M-AT.) Battery voltage
@ Approx.
OV
PNP switch
"2"
<"33 position
(c > is used for M-AT.) Selector lever:
"1"
&?"2 position
Selector lever;
Exce~t
"1"
<"2"> ~osition Battery voltage
gz
A~~rox.
OV
PNP switch
"Dm position Selector
lever:
2" <3*> position
Selector lever: Except
"Y 4'3'5 position
Selector lever;
"Dn
position Battery voltage
Approx. OV
Battery voltage
Neutral signal
(PNP switch
"N-P"
position)
- -- Selector lever: Except "Dm position Approx.
OV
PNP switch
"Rn
position RR Selector lever: "Nn, "P" position
Selector lever: Except
"N", "Pn position
Selector lever:
"Rn
~osition
I Selector lever: Except "Rn position 1 Approx. OV
U" " Approx. OV
Approx. 4.7V
. Batterv voltaae ST
I
After engine warm-up, depress accelerator pedal
partially. (Throttle opening: More than 50%) Battery voltage i% Full
switch
(in throttle position switch)
I After engine warm-up, release accelerator pedal. I Approx. OV
Sensor ground
Throttle position sensor
power -- -- - - - I
-- --- Turn iqnition switch ON. Ao~rox. OV @z!.
Shift control signal SB2
(Except RB20DE) Turn ignition switch
ON. Turn ignition switch
OFF.
Approx.
4.5 - 5.5V
Approx. OV
EL
Vehicle speed sensor 1
(Output shaft speed sensor) When vehicle
cruises at 30 kwh (Inspected in AC posi-
tion) More
than approx. 1 V
80
(Voltage increases in
resDonse to vehicle
meed.)
Turbine sensor (Except
RB20DE)
When vehicle parks (Inspected in AC position)
When turbine rotates at approx. 1,000
rpm I Approx. 0.1 V
Approx.
OV
rn fluid temperature sensor 5 I A/l fluid temperature: Approx. 20°C Approx. 1.5V
c
3 V) Battery voltage
Approx. OV .- Y .- c a, -
Afr mode switch (POWER)
(Except M-AT)
A/T fluid temperature: Approx. 80°C ,
AIT mode switch: POWER
A/T mode switch: Except POWER - - - - - - -- Shift control signal DB1
(Except RB20DE)
Shift control signal
DB3
(Except RB20DE) Approx. 0.5V
Overdrive control switch
(Except M-AT) Battery voltage
z g 0
Shift
control signal DB2
(Except RB20DE)
A/T mode switch (SNOW)
(Except TCS) Overdrive
control switch: ON (Contact: OFF)
- .= c .- & .&!
- 5
Stop lamp switch Overdrive
control switch:
OFF (Contact: ON)
CONSULT
(RX) signal Approx.
OV
Battery voltage Appro~. OV
Battery voltage
Approx. OV
.z w .- cJ=- T) .g
2
CONSULT (TX) signal
A/l mode switch: SNOW
A/l mode switch: Except SNOW
Depress brake pedal.
' Release brake pedal.
*: Each number in parenthesis ( ) shows the terminal No. for TCM (RB25DE).
AT-1 1

TROUBLE DIAGNOSES
n t
\-Test port for "D", "2", and "1" positions
I 'Test port for "I?" position I
Line pressure specification
Basic Inspection
Arr FLUlD
Check A/T fluid for leakage and fluid level.
Check A/T fluid status.
SHIFT CONTROL
Check and adjust A/T position.
Line Pressure Test
1. Check engine oil level. If necessary, add oil.
2. Drive vehicle for approximately 10 minutes until A/T fluid
reaches normal operating temperature between
50 and 80°C,
and check A/T fluid level. If necessary, add fluid.
When
ambient temperature is 20°C, A/T fluid operating tem-
perature
usually becomes between 50 and 80°C for approxi-
mately
10 minutes' drive in urban traffic.
3. After warming up IW', remove fluid pressure detection plug,
and install pressure gauge (Special Service Tool:
ST2505
S001) to corresponding line pressure port.
CAUTION:
0 To remove or install the fluid pressure detection plug, use
standard socket wrench (width across flat:
12 mm).
Detection plug should not be reused because thread-lock
compound is applied
to the plug.
4. Set parking brake and block wheels.
5. Start engine and measure line pressure at idle and stall speed.
CAUTION:
When measuring line pressure, depress brake pedal fully.
When measuring line pressure at stall speed, refer to
"Stall Test" (AT-17).
I p- Line pressure MPa (kg/crn2)
Engine speed
I "RW position "On, 'Z", "1" positions (4AT)
"Dm,
"3", "2" positions (M-AT)
At idle speed
At stall speed 0.58 - 0.62 (5.9 - 6.3) 0.47 - 0.51 (4.8 - 5.2)
1.71
- 1.78 (1 7.4 - 18.2) 1.22 - 1.29 (1 2.4 - 13.2)

TROUBLE DIAGNOSES
Line Pressure Test (Cont'd)
JUDGEMENT OF LINE PRESSURE TEST
At idle
speed
At stall
speed Judgement
Line pressure is low in all
positions.
Line pressure is low in par-
ticular position.
Line pressure is
high.
Line pressure increase is
poorer than that measured at
idle speed.
Line pressure increases but
does not reach specification.
Line pressure is low in par-
ticular position. Possible
causes
Pressure supply system malfunction or low oil pump output
Examples:
0 Oil pump wear
Control piston damage
Pressure regulator valve or plug sticking, and weak spring
Fluid pressure leakage between oil strainer and pressure regulator valve through oil Eg
Pump
Low idle speed
After line pressure is supplied from manual valve, fluid pressure may leak between devices
or circuits of corresponding position.
1
Malfunctions of sensors or pressure regulation function. El
Examples:
Misadjustment of throttle position sensor
PJT fluid temperature sensor damaged ST
Poor operation of line pressure solenoid (stuck with OFF status, clogged filter, or open
harness)
Pressure modifier valve sticking F%
Pressure regulator valve or plug sticking
Malfunctions of sensors or pressure regulation function
Examples:
EILA
Misadjustment of throttle position sensor
TCM, ECM.TCM damaged la
Poor operation of line pressure solenoid (stuck or shorted with ON status)
Pressure regulator valve and plug sticking
Pressure modifier valve sticking
sf$
Pilot valve sticking and pilot filter clogged
Malfunctions of pressure supply system, sensors, or pressure regulation function
Examples:
Misadjustment of throttle position sensor
Control piston damage
Poor operation of line pressure solenoid, and filter sticking or clogged
Pressure regulator valve and plug sticking
Pressure modifier valve sticking
Pilot valve sticking and pilot filter clogged
After line pressure is supplied from manual valve, fluid pressure
may leak between devices
or circuits of corresponding position.
Stall Test
1. Check engine oil level. If necessary, add oil.
2. Drive vehicle for approximately 10 minutes until A/T fluid
reaches normal operating temperature between
50 and 80°C,
and check A/T fluid level. If necessary, add AfT fluid.
When ambient temperature is
20°C,
A/T fluid operating tem-
perature usually becomes between 50 and
80°C for approxi-
mately
10 minutes' drive in urban traffic.
3. Set parking brake and block wheels.
4. Statt engine, depress brake pedal, and move selector lever to
"D" position.

TROUBLE DIAGNOSES
Stall Test (Cont'd)
JUDGEMENT OF STALL SPEED
5. Depress accelerator pedal gradually while depressing brake
pedal.
6. Read stall speed quickly, and immediately release accelerator
pedal.
CAUTION: Do not
depress accelerator pedal for more than 5 seconds
when testing.
7. Move selector lever to "N" position.
8. Cool down fluid.
CAUTION:
Run engine at idle
for at least one minute.
Specification:
RB20DE 2,300 - 2,500 rpm
RB25DE 2,350 - 2,550 rpm
RB25DET 2,920 - 3,170 rpm
7 Lever position
Stall
speed status Possible causes
Forward
clutch
Forward one-way clutch
Low one-way clutch
Engine and torque converter one-way clutch
7-
0
Line pressure circuit (line pressure drop), forward clutch, low one-way clutch
and forward one-way clutch
Line pressure circuit (line pressure drop), reverse clutch and forward clutch
Forward clutch, low one-way clutch, forward one-way clutch, reverse clutch
and forward clutch
Line pressure circuit (line pressure drop), forward clutch, low one-way clutch,
forward one-way clutch, reverse clutch and
forward clutch
Clutches and brake are normal except high clutch, brake band, and overrun
It
I
0
0 0 Low & reverse brake
Reverse clutch
0: Within stall speed specification
H: Higher than stall speed specification
L: Lower than stall speed specification
0 0 0 clutch. (However, status of high clutch, brake band, and overrun clutch cannc
be confirmed by stall test.)

TROUBLE DIAGNOSES
CONSULT (Cont'd)
SELF-DIAGNOSTIC RESULTS MODE
Diagnostic item 1 Diagnostic item is detected when ... Inspection item - -- -
I TCM does not receive vehicle speed sensor 1 signal due to
open circuit, etc.
TCM receives improper signal during driving. After ignition switch is turned ON, vehicle speed sensor 2 receives improper signal until vehicle starts to run.
VHCL
SPEED
SEN.A/T Vehicle
speed sensor 1 circuit
TCM does not receive vehicle speed sensor 2 signal due to
open circuit, etc.
TCM receives improper signal during driving.
VHCL
SPEED
SEN.MTR Vehicle
speed sensor 2 circuit
TCM detects
folfowing conditions during driving (Except N and
P positions). 0 Excessively high throttle position sensor signal voltage Excessive1 low throttle position sensor signal voltage with idle
switch OF; or full switch ON
THROTTLE
POSl
SEN
Throttle position sensor circuit
SHIFT SOLENOIDN A
SHIFT SOLENOIDN B Shift
solenoid A circuit
Shift solenoid
B circuit
Overrun clutch solenoid circuit
TIC
CLUTCH SOW
I
OVERRUN CLUTCH SN
Lock-up solenoid circuit Specified voltage is not applied to solenoid due to open and/or
short circuit.
LINE
PRESSURE SN
I Line pressure solenoid circuit
0 Excessively low supply voltage to TCM during driving
Excessively high si nal voltage of AIT fluid temperature sensor
(excessively low d fluid temperature) during driving This message is displayed only when malfunction occurs with ignition switch ON, and does not have memory func-
tion.
fluid temperature sensor circuit,
TCM power supply circuit, or
throttle position sensor power sup-
ply circuit
BATT/FLUID
TEMP SEN
ENGINE SPEED SIG
I Excessively low engine speed during driving Engine speed
signal circuit
Turbine sensor circuit
TURBINE
SENSOR
(Except
RB20DE)
SHIFT SOLENOIDN C
(Except
RB20DE)
TCM does not receive input shaft speed sensor signal due to
open circuit,
etc.
0 TCM receives improper signal during driving.
0 TCM does not receive shift solenoid A pressure detection switch
signal due to open
andfor short circuit. Shift solenoid A pressure
detection
switch circuit
MANUAL MODE SW
(Except
RB20DE)
TCM does not receive proper manual mode switch signal due to
open and/or short circuit. Manual
mode switch circuit
ENGINE BRAKE
C/U'1
(Except
RB20DE)
Shift control unit does not operate properly due to open and/or
short circuit of each
input/output signal wire.
Malfunction occurs in shift control unit. Each
signal wire circuit connected
to shift control unit
'INITIAL START*
Power supply to TCM is shut down, and self-diagnostic memory
function is canceled due to battery removal, etc.
CONTROL UNIT (RAM)
I Malfunction is detected in TCM memory (RAM) function.
CONTROL
UNIT
(ROM)
I Malfunction is detected in TCM memory (ROM) function.
'1 : Indicates shift control unit.
DATA MONITOR PROCEDURE
Refer to "CONSULT Instruction Manual - Supplement" and "CON-
SULT Service Manual
- Supplement" in details.
1. Turn ignition switch OFF.
2. Connect CONSULT connector to data link connector.
3. Turn ignition switch ON.
4. Touch "START', ''AT and "DATA MONITOR" sequentially on
CONSULT screen.

TROUBLE DIAGNOSES
Symptom Chart
Sharp shock in Engine brake
applied
Shifting
Malfunctions
Slip
(Racing)
hifting
.- erator pedal
Shifting
Shifting
inspection item
Fluid level and status
Control linkage
PNP switch (short/open circuit)
Throttle ~osition sensor (installed)
I Vehicle weed sensor
I Enaine meed sensor
A/T fluid temperature sensor
Engine idle speed
Line
Dressure
Control valve assembly
Shift solenoid
A
Shift solenoid B
Line pressure solenoid
Lock-up solenoid
Overrun clutch solenoid
Accumulator N-D
Accumulator
1-2
Accumulator 2-3
Accumulator 3-4 (N-R) Ignition coil and starter motor
Overdrive control switch
I AfT mode switch (AUTO)
Torque converter
1 Oil pump
I Reverse clutch
I High clutch
I Forward clutch
I Forward one-wav clutch
I Overrun ciutch
1 Low one-wav clutch
I Low reverse brake
Brake. band (including servo)
Parking linkage

Symptom Chart (Cont'd)
Greater noise
Malfunctions
Inspection item No shifting
I Shifting I
Fluid level
and status 11
Control linkage
-
(I) C 0 .- c. .- (I) 0 a
v
-CU
n - 1
PNP switch
(shortlopen
circuit)
Throttle position sensor (installed)
2 2
Vehicle speed sensor
I Engine speed sensor -
-T
L o 1 Control valve assembly .- - -- Shift solenoid A 4 3
. ' Shift solenoid 6 4 cut I1
--, Line pressure solenoid .- 5 -t Lock-up solenoid ?
6 Overrun clutch solenoid 3
Accumulator N-D
1 Accumulator 1-2 I 1-
Accumulator 2-3
Accumulator 3-4 (N-R)
Ignition coil and starter motor
I Overdrive control switch I 1-
A/T mode switch (AUTO)
A/T mode switch (POWER) I - I Ail mode switch (SNOW) I
I Torque converter I I
1 Oil pump I I -- - - Reverse clutch 0 -
'g High clutch a 4 6
%I Forward clutch I I - .- a Forward one-way clutch -
$ Overrun clutch a, 8
Low one-way clutch
O Low reverse brake 7
Brake band (including servo) 7
Parking linkage