ignition NISSAN GT-R 1998 Workshop Manual

ANTI-LOCK BRAKE SYSTEM
Self-diagnosis
DESCRIPTION
When a problem occurs in the ABS, the ABS warning lamp on the
instrument panel comes on. To actuate the self-diagnostic results
mode, ground the self-diagnostic check terminal
4 located on the
data
link
connector for
CONSULT. The ABS warning lamp, then,
flashes and indicates the location of the malfunction.
SELF-DIAGNOSIS PROCEDURE
1. Collect information on the concern from the customer, and then
perform basic inspections.
2. Drive vehicle at approx. 30 km/h for approx. 1 minute.
3. Stop vehicle and start diagnosis.
4. Turn ignition switch "OFF'.
5. Ground the self-diagnostic check terminal 4.
6. Turn ignition switch "ON" to start the self-diagnostic results
mode.
CAUTION:
Keep terminal 4 grounded during self-diagnosis.
Do not depress brake pedal. (Self-diagnosis would not
start.)
Do not start engine. (Self-diagnosis would not start.)
7. After 3 or 4 seconds, ABS warning lamp starts blinking to indi-
cate the malfunction code No.
The indication terminates after 5 minutes. Turning the ignition
switch from
"OFF" to "ON" resumes blinking the indication.
8. Verify the location of the malfunction with "MALFUNCTION
CODUSYMPTOM CHART", BR-16. Then make the necessary
repairs.
9. After the malfunctions are repaired, erase the malfunction
codes stored in the control unit. Refer to "HOW
TO ERASE
SELF-DIAGNOSTIC RESULTS" on the next page.
10. Rerun the self-diagnostic results mode to verify that the mal-
function codes have been erased.
11. Disconnect the check terminal from the ground. The self-diag-
nostic results mode is now complete.
12. Drive vehicle at approx. 30 km/h for approx. I minute, and then
check that the ABS warning lamp is off.
HOW TO READ SELF-DIAGNOSTIC RESULTS
(Malfunction codes)
Determine the code No. by observing the time and the fre-
quency that the
ABS warning lamp blinks ON and OFF.
When multiple malfunctions occur at a time, up to three code
numbers can be stored; the latest malfunction will be indicated
first.
The indication begins with the start code No. 12. A maximum
of three code numbers appear in the order of the latest one
first. The indication then returns to the start code No.
12 to
repeat.
The start code No. 12 is only indicated repeatedly when there
is no malfunction.

ANTI-LOCK BRAKE SYSTEM
Self-diagnosis (Cont'd)
Example: Code No. 25 Front left wheel sensor (open-ccrcuit)
lnd~cat~on
s:arl
Start code No. i2
Unit: seconds BRG1185D
ABS warnq lamp ON -
A9S warnrng lamp OFF
Self-d~agnosis complete , C ABS warning lamp !
I i I I I
................ &. j(j(?.:e~o"dd~i!~?!!f!!. . -----... .-.---.--. iiii rase 1 12.5 seconds I mode
Malfunct~on
memory Malfunction memory is Nn. erase mode starts. Is erased BRG0057C
Tens d~g~ts Un~ts digits Code No 25 I I - I
HOW TO ERASE SELF-DIAGNOSTIC RESULTS
(Malfunction codes)
r--------- -T---t----t-l-T-l-
1. Turn the ignition switch "ON" and start the engine.
-.
---------- -I--I--t--l-i-"I
2. Drive the vehicle at approx. 30 kmh for approx. 1 minute to
check that there is no other malfunction.
ST
3. Stop the vehicle.
4. Turn the ignition switch "OFF'.
5. Ground the self-diagnostic check terminal. RS'
6. Turn the ignition switch "ON" to start the self-diagnostic results
-
-.
3 06 0.9 03C303 3.3 06 0.6 0.6 09 050303030305030303
-----
mode.
CAUTION:
c--
Do not depress the brake pedal during self-diagnosis. Do not
start the engine. (The self-diagnosis
would not start.)
7. The ABS warning lamp starts to blink 3 or 4 seconds after the EL
self-diagnostic results mode is started.
8. Under the self-diagnostic results mode, the malfunction $jD
memory erase mode starts when the check terminal is discon-
nected from the ground.
9. Ground the check terminal 3 times or more in succession
within 12.5 seconds after the erase mode starts. (Each ground-
ing must
be 1 second or longer.)
10. Disconnect the grounding cable from the check terminal to
erase the malfunction memory and complete the
self-diagno-
sis. The ABS warning lamp
, then, turns off.
11. Turn the ignition switch
"OFF'.

ANTI-LOCK BRAKE SYSTEM
Self-diagnosis (Cont'd)
MALFUNCTION CODEISYMPTOM CHART
Malfunction code No. Malfunctioning
part ABS warning
lamp
ON
Fail-safe
operation
18 1 Different number of teeth of sensor rotors 1010
2 1
26 I Front left wheel sensor (short-circuiQ.4 1010
- --
22
25
3 1 I Rear wheel sensor (open-circuit) 1010
Front right wheel sensor (open-circuit)
32 Rear wheel sensor (short-circuit)'4 1 0 1 0
Front right wheel sensor (short-circuit)'4
Front left wheel sensor (open-circuit)
41
I Front right outlet ABS solenoid valve and circuit 1010
0 0
0
0
0
0
- -
42
-- - -
46 Front left inlet ABS solenoid valve and circuit 0 1 0
45 Front
left outlet ABS solenoid valve and circuit
55
1 Rear outlet ABS solenoid valve and circuit 1010
Front right inlet ABS solenoid valve and circuit
56
1 Rear inlet ABS solenoid valve and circuit 1010
0
57 1 Power supply (Low or high voltage)*2 I 0 I -'I
0
0
0
I At self-diagno- ( ABS control unit or data link connector for CONSULT is poorly 1 I
61
63
At self-diagno-
I ABS control unit
sis only
ABS
actuator motor or motor relayg3
ABS
actuator relay
No indication
I I ABS control unit1ABS actuator relay is stuck to OFFJABS I Stays ON power supply circuit, ABS actuator relay drive side power sup-
lgnition switch
ply (coil side) circuit, and ABS warning lamp circuit are
short-
circuited./ABS control unit connector is disconnected or poorly
0
0
I
sis only
Ignition switch
ON
I I connected. I I
0
0
connected.
ABS control
unit1Fuse is blown or ABS warning lamp has an
open circuit.
- -- '1: Fail-safe operation does not activate. A signal from ABS control unit suspends ABS control operation. Brakes operate con-
ventionally. After specified power supply voltage resumes, ABS warning lamp goes out, allowing for ABS control operation. '2: The code No. does not indicate a malfunction related to the ABS control unit. Do not replace the ABS control unit even if the code No. appears. '3: The code No. can sometimes appear when the ABS motor ground circuit is loose or disconnected. When it appears, always
check the ground circuit for improper installation.
'4: ABS warning lamp turns on if a wheel or wheels spin for 10 to 80 seconds (depending on the wheel speed) with the vehicle
stuck in snow, ice, or mud. This is a normal condition. After repairing short-circuited sensor, turning ignition switch ON lights
up
ABS warning lamp. Check that ABS warning lamp turns off when the vehicle is driven at approx. 30 krnlh for approx. 1 minute as shown in the self-diagnosis procedure.

TCSIABS SYSTEM
Control Unit
InputlOutput Signal Specifications
USING CIRCUIT TESTER
TCS/ABS control unit - -
To perform the following inspection, the ignition switch should be turned ON with TCS/ABS control unit con-
nector and actuator connector properly connected.
I
TCS/ABS contro! unit connector
Terminal No.
P Front right wheel I
Item
sensor
I
Specifications'l
Rear right wheel Wheels are turning (Approx.
30 km/h)'3: Pulse generates.
Front: Approx. 200
Hz
Rear: ADDrox. 200 Hz I . , sensor
Rear left wheel
sensor
I
I
Brake pedal is depressed: Battery voltage (Approx. 12V)
Stop lamp signal Brake pedal is not depressed: Less than approx. 2V
Actuator relay is activated (with engine running): Less than approx.
2V
Actuator relay Actuator relay
is not activated (with fail-safe function activated and engine
not running): Battery voltage (Approx.
12V)
ABS motor is running (in CONSULT active test mode): Battery voltage
ABS motor monitor (Approx. 12V)
ABS motor is stopped (with ignition switch ON): Approx. OV
SLIP
indicator
SLIP
indicator lamp
ON'S: OV
lamp
SLIP
indicator lamp
OFF'5: Battery voltage (Approx. 12V)
TCS OFF indicator TCS OFF indicator lamp
ON'4: OV
lamp TCS OFF indicator lamp
OFF'4: Battery voltage (Approx. 12V)
TCS OFF switch TCS OFF switch is pressed: Approx. OV
signal TCS OFF switch is not pressed: Approx. 4
- 5V
Engine speed sig-
nal Pulse generates.
Refer to EC section
("ECM.TCM Input/Outout Reference Value")
Total control signal
(Multiple communi-
cation) for engine,
A/T and TCSIABS Check item (Refer-
ence)
Wheel sensors
and circuit Stop lamp switch
and circuit
ABS actuator relay
and circuit
ABS motor monitor
circuit
SLlP indicator
lamp and circuit
TCS OFF indicator
lamp and circuit
TCS OFF switch
and circuit
Engine speed sig-
nal circuit
Circuit for total
control signal (Mul-
tiple communica-
tion) for engine, A/T and TCSIABS

TCS/ABS SYSTEM
Control Unit InputlOutput Signal Specifications
(Cont'd)
Terminal No.
Specifications'l
- - --
Check item (Refer-
ence)
- - -
Body
ground
-
Approx. 7V - - or higher Communication
line circuit between
TCSIABS control
unit and throttle
control unit
DKV
(throttle angle
output)
Acceleration pedal is released: approx. 1 ms (reference)
ABS warning lamp ABS warning
lamp
and circuit 4B3 warning lamp 0Nr2: Approx. OV
4BS
warning lamp 0FF72: Battery voltage (Approx. 12V)
cictuator
relay is activated (with engine running): Battery voltage
(Approx.
12V)
ktuator
relay is not activated (with fail-safe function activated and engine
70t
running): Approx.
OV
ABS warning lamp
and circuit,
ABS
actuator relay and
circuit
Actuator relay
monitor
48s
motor is running (in
CONSULT active test mode): Less than approx.
2V
4BS motor is stopped: Battery voltage (Approx. 12V)
TCS is not activated: ABS
motor, motor
relay and circuit
ABS
motor relay
Approx. 7V - -
OV I I Communication
line circuit between TCSfABS control
unit and throttle
control unit
DKR
(throttle
motor target angle
signal) Approx. 9 ms (Reference)
Front
right inlet
solenoid
Front right outlet
solenoid
4ctuator
is activated (in CONSULT active test mode), or actuator relay is
lot
activated (with fail-safe function activated and engine not running):
4pprox.
OV
4ctuator
is not activated and actuator relay is activated (with vehicle
stopped and engine running): Battery voltage (Approx.
12V)
Rear inlet solenoid
Rear outlet
sole- ABS solenoid and
circuit
Front left inlet
solenoid
Front left outlet
solenoid
Battery gnition switch
ON: Baitery voltage
(Approx. 12V) Control
unit power
supply circuit
'1: Do not force to oDen a connector terminal when usina a circuit tester for ins~ection. '2: ABS warning lamp ON: When the ignition switch is t6ned ON (before startirig the engine) or a malfunction is detected
ABS warning lamp OFF: When the engine has started (with the system in normal condition)
'3: Tire pressure must be in accordance with specification. '4: TCS OFF indicator lamp ON: When the ignition switch is turned ON (before starting the engine), a malfunction is detected,
or TCS OFF switch is turned ON TCS OFF indicator lamp OFF: When the engine has started (with the system in normal condition) and the TCS OFF switch
is off '5: SLlP indicator lamp ON: When the ignition switch is turned ON (before starting the engine) or a malfunction is detected
SLlP
indicator lamp OFF: When the engine has started (with the system in normal condition) and the TCS is inoperative

TCS/ABS SYSTEM
Control
Unit InpuVOutput Signal Specifications
(Cont'd)
Throttle control unit
Terminal No.
Specifications*
item Check
item (Refer-
ence)
Throttle angle sig-
nal Ignition switch
ON
Throttle valve is fully closed: Approx.
0.5V
Throttle valve is fully open: Approx.
4.2V
Throttle motor sen-
sor
Throttle motor angle signal Throttle
position
sensor circuit and
ECM
I
Throttle motor sen-
sor and circuit R8 Engine is idling: Approx. 4.4V
I
I Throttle motor
TCS switch signal Engine
is idling: Approx.
3.4V
lgnition switch ON: Approx. 5V
Throttle control
unit power supply angle
signal and
MA
circuit
TCS switch signal
circuit
EL
Body
jround
- - -- -- - - - --
lgnition switch ON: Battery voltage (Approx. 12V)
Throttle control
unit power supply
Throttle motor relay
Sensor battery
voltage
Throttle control
unit power supply
Throttle motor relay Throttle
control
unit power circuit @J
1
Throttle control
unit power circuit
lgnition switch
ON: Battery voltage (Approx.
12V)
Throttle motor relay and circuit
lgnition
switch ON: Approx.
OV
Throttle position
sensor power cir-
cuit
lgnition
switch ON: Approx. 5V
lgnition switch ON: Battery voltage (Approx. 12V) Throttle control
unit power circuit
lgnition switch ON: Battery voltage (Approx. 12V)
I
Throttle motor
relay
and circuit
Start signal lgnition
switch START (Disconnect ECM-TCM connector or ECM connec-
tor.): Approx.
10V
*: Do not force to open a connector terminal when using a circuit tester for inspection. Start
signal circuit
and ECM

TCSlABS SYSTEM
Control Unit InputfOutput Signal Specifications
(Cont'd)
USING CONSULT
Indicated are the controi unit computed data. If the output circuit (harness) should be open or short-
circuited, correct values may be displayed.
TCS/ABS control unit
Display
I Vehicle is stationary.
REVOLUTION SENSOR
W/hI
STOP LAMP SW [ON-OFF] Check
item (Reference)
Data monitor
the
same 'peed Wheel sensor circuit
as speedometer (within
~onttor
ltem
Wheel
speed'l
Vehicle is
driven.'l
Condition
Brake pedal is
Brake pedal is not
depressed.
Engine is stopped.
Engine is running at
more than
400 rpm.
Actuator (solenoid) is
activated (at CONSULT Specifications
Brake pedal status
-1 Engine speed signal cir-
cuit
ENG
RPM SIGNAL
[STOP-RUN] Engine operation
active test), or actuator
relay is not activated
(with fail-safe function
activated and engine not
running). Solenoid circuit
IN
ABS SOLENOID
[ON-OFF]
Solenoid status Actuator (solenoid) is
not
activated and actuator
relay
is activated (with
vehicle stopped and
engine running).
OUT
ABS SOLENOID
[ON-OFF] OFF
Actuator relay is acti-
vated (with engine run-
ning).
ABS ACTUATOR RELAY
[ON-OFF]
- Actuator relay and circuit
Actuator
relay status
Actuator relay is not acti-
vated (with fail-safe
function activated and
engine not running).
Motor relay and motor
are activated (at CON-
SULT active test).
Motor relay and motor
are not activated. OFF
I ABS
motor, motor relay
ABS MOTOR
RELAY
[ON-OFF]
Motor
relay
and motor
status
OFF and circuit
ABS warning lamp cir-
cuit
Controi unit power
sup-
WARNING LAMP
[ON-OFF]
4BS
warning lamp
sta-
:us'2
Warning lamp ON Warning lamp OFF
'ewer supply voltage
~rovided for control unit
BATERY
BOLT [V] Ignition switch ON
Acceleration pedal is not
depressed. (Ignition
switch
ON)
10 - 16V
I
Communication line cir-
cuit between TCS/ABS
control unit and throttle
I - 10096 control unit ply circuit and ground
circuit
rhrottle
angle condition
linked with acceleration
~edal)
THRTL OPENING
[%]
Acceleration pedal is
depressed. (Ignition
switch ON)

TCS/ABS SYSTEM
Control Unit Input/Output Signal Specifications
(Cont'd)
THRTL OPENING TAR-
GET
[%]
Display Monitor item
Motor throttle angle con-
dition
TCS
MODET3
TCS OFF LAMP Data monitor I Condition
Specifications
TCS is inoperative.
TCS is operational.
Communication line
cir-
TCS is inoperative.
Number of cylinders to cuit between
TCS/ABS
which fuel is cut off control unit and
I.z /LT TCS is operational.
ECM-TCM or ECM
GEAR
TCS
SW
TCS OFF indicator lamp
TCS OFF indicator lamp
status
1 1 lEi3FF indicator amp
TCS OFF indicator lamp
@
Check item (Reference)
SLlP LAMP
0%
0 - 100%
Gear selection
TCS OFF switch status (ONIOFF)
P/N POSITION SIGNAL Communication line cir-
@
cuit
between TCSIABS
control unit and throttle
control unit
lzc
SLlP indicator lamp is / ow
TCS OFF switch circuit ST
I
1: 1st gear 2: 2nd gear 3: 3rd gear
4: 4th gear 5: 5th gear
SLIP
indicator lamp
sta-
cuit
TCS switch ON
TCS switch OFF
PNP switch signal or
neutral position switch
signal status (ONIOFF) ON
OFF
SLlP indicator lamp is
ON.
( A/T selector position: I I
I %~hift position: I ON
ON
SLIP indicator lamp cir-
1 Other than Neutral I 1
Neutral
A/T selector position:
Other than N and P
MA' shift position:
A/T PNP switch or neu-
tral position switch circuit
OFF
'1: Tire pressure must be in accordance with specification.
'2: ABS warning lamp ON: When the ignition switch is turned ON (before starting the engine) or a malfunction is detected ABS warning lamp OFF: When the engine has started (with the system in normal condition) '3: TCS mode: 0 - 24, number of cylinders to which fuel is cut off x 4
Throttle control unit
THRTL POS SEN
Display
TH MOTOR VOLT Monitor item I Sensor
voltage (V)
Sensor voltage
(V)
Throttle valve is fully
I Approx. 0.5V closed.
Engine is idling.
I
Data monitor
Approx. 3.4V
Condition
TH OPEN CONT Specifications
Motor throttle target
angle signal (ms)
NEUT
POSl
SW
START
SIGNAL
ONIOFF TCS
is inoperative
Shift (selector) lever is in
parkheutral
position. Approx.
9 ms Check
item (Reference)
ON
1
Throttle position sensor
circuit
ONIOFF Throttle motor sensor
circuit
Communication line cir-
cuit between
TCS/ABS
control unit and throttle
control unit
Start signal circuit
ParWneutral position
switch circuit
Ignition switch
ON
I

TCSlABS SYSTEM
Precautions for Trouble
Diagnosis
After performing trouble diagnosis, be sure to erase trouble stored in memory.
Refer to "CONSULT for
TCS/ABS Control Unit Control System"
(BR-27), "Self-diagnosis for TCSIABS
Control Unit Control System"
(BR-34), "CONSULT for Throttle Control Unit Control System" (BR-37) or
"Self-diagnosis for Throttle Control Unit Control System"
(BR-41).
The concerns that are difficult to duplicate may be caused by faulty electrical connections. Move harnesses
or harness connectors by hand to check if there is any poor mating of connector halves or faulty connec-
tion. Do not force to open a connector terminal when using a circuit tester for inspection.
Read GI section thoroughly in advance and make sure of all the general precautions.
Basic Inspection
BASIC INSPECTION 1 - Brake fluid level and leakage
1. Check brake fluid level in reservoir tank. Replenish brake fluid if necessary.
2. Check for leakage at or around brake piping and ABS actuator. If leakage or seepage is noted, proceed
as follows:
If ABS actuator connectors are loose, tighten to specified torque. Recheck to ensure that leakage is no
longer present.
If flare nut threads at piping connectors or actuator threads are damaged, replace faulty parts with new
ones. Recheck to ensure that leakage is no longer present.
If brake fluid leaks through areas other than actuator connectors, wipe off using a clean cloth. Recheck
for leakage or seepage. If necessary, replace faulty parts with new ones.
If brake fluid leaks at or seeps through ABS actuator, wipe off using a clean cloth.
Recheck for leakage or seepage. If necessary, replace ABS actuator with new one.
CAUTION:
ABS actuator cannot be disassembled. Do not attempt to disassemble it.
3. Check brake disc rotors and pads for proper operation.
BASIC INSPECTION 2 - Loose power line terminal
Check battery terminals (positive and negative) and battery mounting (ground) for looseness. If necessary,
tighten to specified torque. Check the battery for lower voltage.
BASIC INSPECTION 3 - SLlP indicator lamp, TCS OFF indicator lamp and ABS warning
lamp
Turn ignition switch "ON" to ensure that TCS OFF indicator lamp lights up. If TCS OFF indicator lamp does
not light, check TCS OFF indicator lamp circuit.
Turn ignition switch
"ON" to ensure that SLlP indicator lamp lights
up. If SLlP indicator lamp does not light,
check SLlP indicator lamp circuit.
Turn ignition switch "ON" to ensure that ABS warning lamp lights up. If ABS warning lamp does not light,
check ABS warning lamp circuit.
Check that the SLlP indicator lamp and the ABS warning lamp go off approx.
1 second after the engine
has started. If either of the lamps still remains on, perform the self-diagnosis for TCSIABS control unit
control system and the self-diagnosis for throttle control unit control system.
After driving vehicle at approx. 30
km/h
for approx.
1 minute, check to ensure that the SLlP indicator lamp
and the ABS warning lamp are off. If either of the lamps still remains on, perform the self-diagnosis for
TCS/ABS
control unit control system and the self-diagnosis for throttle control unit control system.
Check that the TCS OFF indicator lamp turns ON and OFF when the TCS OFF switch is turned to
ON
and OFF respectively, with the engine running. If the lamp status does not correspond to the switch
position, check the TCS OFF switch circuit.
Check that the TCS OFF indicator lamp goes off when the engine has started with the TCS OFF switch
OFF. If the TCS
OFF indicator lamp does not go off even 10 seconds after the engine has started, per-
form the self-diagnosis for TCSIABS control unit control system and the self-diagnosis for throttle control
unit control system.
After driving vehicle at approx.
30 kmlh for approx. 1 minute with the TCS OFF switch OFF, check to ensure
that the TCS OFF indicator lamp is off. If the TCS OFF indicator lamp lights up, perform the
self-diagno-
sis for
TCS/ABS
control unit control system and the self-diagnosis for throttle control unit control system.
After performing self-diagnosis procedures, be sure to erase trouble stored in memory.

TCS/ABS SYSTEM
CONSULT for TCS/ABS Control Unit Control
System
CONTROL UNIT PART NUMBER
The part number that is shown on the control unit label and CON-
SULT
A/T model: 47850 AA310
M/T model: 47850 AA110
SELF-DIAGNOSIS PROCEDURE rn
Collect information on the concern from the customer, and then
perform basic inspections.
Turn ignition switch OFF and connect CONSULT connector to
data link connector for CONSULT on the vehicle.
ST
Start engine and drive vehicle at approx. 30 km/h for approx.
1 minute.
Stop vehicle with engine running and touch "START", "ABS"
38
and "SELF-DIAG RESULTS" sequentially on the CONSULT
screen.
If "START" is touched immediately after engine is started y;rjn
or ignition switch is turned on, "ABS" may not be dis-
played on "SELECT SYSTEM" screen. To display "ABS", E~
repeat the self-diagnosis procedure from the beginning.
Self-diagnosis results are displayed on the screen. (Touch
"PRINT' to print out the self-diagnosis results,
if necessary.) 8~ If "NO FAIL" is displayed, inspect the SLlP indicator lamp, the
TCS OFF indicator lamp and the ABS warning lamp. Refer to
the previous page.
Perform appropriate inspection from the self-diagnostic results
mode and repair or replace faulty parts.
Start engine and drive vehicle at approx.
30 km/h for approx.
1 minute.
Recheck to ensure that there is no other malfunction.
Turn ignition switch OFF to prepare for erasing the trouble
stored in memory.
Start engine and touch "START",
"ABS", "SELF-DIAG
RESULTS" and "ERASE" sequentially on the CONSULT
screen to erase the trouble stored in memory.
If the trouble stored in memory is not erased, repeat step
6.
Drive vehicle at approx. 30 krn/h for approx. 1 minute and then
confirm that the TCS OFF indicator lamp, the
SLlP indicator
lamp, and the ABS warning lamp are OFF.
TCS OFF switch is not in cancel condition.