1998 NISSAN GT-R brake

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)

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
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'.

TCS/ABS SYSTEM
CONSULT for TCS/ABS Control Unit Control
System (Cont'd)
9. "ACTIVE TEST' screen is displayed.
ABS solenoid valve
a To check that ABS solenoid valves (inlet and outlet) ooerate in
I I I - --
': Solenoid valve stays ON for 1 to 2 seconds after touching the key, and then
turns OFF. =
the following manner, touch "UP", "KEEP" and "DOWN" on the @
screen while observing the monitor.
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
Y
the operation is started. ST
a If the active test needs to be performed again after "TEST IS
STOPPED" is displayed, repeat step 8. RS
Operation
IN ABS
SN
OUTABS SN
ABS motor
Touch "ON" and "OFF' on the screen to check that ABS motor EL
relay and ABS actuator relay operate as follows:
UP
OFF
OFF
Operation ON
@
KEEP
ON
OFF
ABS actuator relay
ABS
motor relay DOWN
Ee
ON
ON'
A'
a If the active test is conducted with brake pedal depressed, the
brake pedal travel limit may change. This is a normal condition.
a "TEST IS STOPPED" message is displayed 10 seconds after
the operation is started.
ON
ON OFF
ON
OFF

TCS/ABS SYSTEM
Self-diagnostic check ter (Terminal 4 of data link c
Data link connector for CONSULT
Self-diagnosis for TCSfABS Control Unit
Control System
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 on the data link
connector for CONSULT.
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. Do not start engine. (Self-diagnosis
would
not start.)
When SLlP indicator lamp does not start blinking, check
TCSfABS
control unit power supply circuit and ground
circuit.
7. The SLlP indicator lamp starts blinking to indicate the malfunc-
tion code No.
3 or 4 seconds after the self-diagnostic results
mode is started.
The indication terminates after 5 minutes. Turning the igni-
tion switch from
"OFF" to "ON" resumes blinking the indi-
cation.
During the SLIP indicator lamp operation shown above,
TCS
OFF indicator lamp and ABS warning lamp are lit.
8. Vsrify the location of the malfunction with "MALFUNCTION
CODUSYMPTOM
CHART", BR-36. 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.
When the malfunction codes have been erased, the start
code is only indicated.
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. 1 minute, and then
check that the
TCS OFF indicator lamp, the SLlP indicator
lamp and the ABS warning lamp are OFF.
HOW TO READ SELF-DIAGNOSTIC RESULTS
(Malfunction codes)
Determine the code No. by observing the time and the fre-
quency that the SLlP indicator lamp flashes ON and OFF.
Refer to the next page.
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. After that 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.

TCS/ABS SYSTEM
Self-diagnosis for TCS/ABS Control Unit
control System (Cont'd)
Example: Code No. 25 Front left wheel sensor (open-circutt)
lnd~cat~on
start Start code No.
12
HOW TO ERASE SELF-DIAGNOSTIC RESULTS
(Malfunction codes)
1. Turn the ianition switch "ON" and start the engine.
ABS warnlng lamp - ON
ABS warning lamp
OFF
2. Drive the iehicle at approx. 30 km/h for appfox. 1 minute to
check that there
is no other malfunction.
3. Stop the vehicle and turn the ignition switch "OFF'. I88
4. Ground the self-diagnostic check terminal 4 on the data link
connector for CONSULT.
5. Turn the ignition switch "ONn to start the self-diagnostic results /,%@A
mode.
I---------- -------------- -?-I 3 06 0.9 03C303 3 3 06 3.6 06 09 030303030303030303
Unit: seconds BRG1185D
Tens drglts Units drgits Code No. 25
I -----l
7. Under the self-diagnostic results mode, the malfunction
memory erase mode starts when the check terminal
is discon-
nected from the ground.
8. Ground the check terminal 3 times or more in succession
-.
self-d~agnosts complete
SLlP ndicator lamp i
I ON r
f OFF - c 4 i
ground J Erase -- - - - - - - - - -i - - - - ---f2.i geconds-- - - - - - - .. t mode
Malfunct~on
memory
Malfunct~on
memory
IS erase mode starts. 1s erased. BRZOO~~D
within 12.5 seconds after the erase mode starts. (Each ground-
ing must be
2 seconds or longer.)
9. Disconnect the grounding cable from the check terminal to
erase the malfunction memory and complete the
self-diagno-
-----
CAUTION:
Keep terminal 4 grounded during self-diagnosis. Do not EL
depress the brake pedal during self-diagnosis. Do not start the
engine.
6. The SLIP indicator lamp starts blinking to indicate the malfunc- SD
tion code No. 3 or 4 seconds after the self-diagnostic results
mode is started.
The indication terminates after 5 minutes. Turning the igni-
tion switch from
"OFF" to "ON" resumes blinking the indi-
cation. During the SLlP indicator lamp operation shown
above,
TCS OFF indicator lamp and ABS warning lamp are
lit.
sis.
10. Rerun the self-diagnostic results mode to verify that the mal-
function codes have been erased.
0 When the malfunction codes have been erased, the start
code No.
12 is only indicated.
11. Disconnect the check terminal from the ground. The self-diag-
nostic results mode is now complete.
12. Drive vehicle at approx. 30 kdh for approx. 1 minute, and then
check that the
TCS OFF indicator lamp, the SLlP indicator
lamp
and the ABS warning lamp are OFF.
13. Turn the ignition switch "OFF.

TCS/ABS SYSTEM
Self-diagnosis for TCSfABS Control Unit
Control System (Cont'd)
MALFUNCTION CODE/SYMPTOM CHART I I I
75, 'I:
'2: '3: '4:
'5:
Fail-safe operation is not activated. A signal from control unit suspends TCS and ABS control operation. Brakes operate
conventionally and the vehicle operates in the same manner as a vehicle without the TCS. After specified battery voltage
resumes, the TCS
OFF indicator lamp and the ABS warning lamp go off, allowing for TCS and ABS control operation.
TCS operation only stops and fail-safe operation is activated, allowing for ABS control operation.
Malfunction is detected only when TCS is in operation.
When there are malfunctions in the self-diagnostic check terminal circuit (terminal
4 of the data link connector for CONSULT)
and SLlP indicator lamp circuit, fail-safe operation is not activated.
Some malfunctions in the
TCS/ABS
control unit cause the SLlP indicator lamp and the
ABS warning lamp to go off sepa-
rately.
Malfunc-
tion code
No.
12
21 22
25
26
31
32
35
36
41
42
45
46
55
56
57
58
61
63
71
75
80
83
84
85
86
NO indi-
cation
(no blink-
ing)
NOTE:
When the
80, 83,
84, 85 or 86 is indicated, perform the self-diaqnosis for ECM-TCM or ECM.
Check
item
Normal
Front right wheel sensor (open-circuit)
Front right wheel sensor (short-circuit)
Front left wheel sensor (open-circuit)
Front left wheel sensor (short-circuit)
Rear right wheel sensor (open-circuit)
Rear right wheel sensor (short-circuit)
Rear left wheel sensor (open-circuit)
Rear left wheel sensor (short-circuit)
Front right outlet solenoid valve and circuit
Front right inlet solenoid valve and circuit
Front left outlet solenoid valve and circuit
Front left inlet solenoid valve and circuit
Rear outlet solenoid valve and circuit
Rear right inlet solenoid valve and circuit
Battery voltage (low)
Throttle control unit system or circuit for the corn-
munication
line between TCSIABS control unit
and
throttle control unit
Actuator motor and motor relay circuit
Actuator relay circuit
TCSIABS
control
unit
Total control signal (multiple signal) for engine,
IVT
and TCS/ABS
Engine speed signal
Monitoring of total control signal (multiple signal) for
engine,
AfT and TCS/ABS
Engine system component fuel condition
Incomplete start process of total control signal (mul-
tiple signal) for engine,
AfT and TCSIABS
Continuous start process of total control signal
(multiple signal) for engine, and
TCS/ABS
Remains OFF: Data link connector circuit
Remains ON: SLIP indicator lamp circuit shorted,
TCSIABS
control unit or self-diagnostic check termi-
nal circuit open
malfunction code No. 58 is indicated, perform the Detection
Engine
running
-
0 -
0
-
0 -
0 -
0
0
0
0
0
0
0
0
0
0
0
0
-
0
0
0
0
0
0
throttle control time
In driving
-
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0 -
0'3
0
0
0
0
0
0
unit
a Fail-safe
operation
-
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-'I
0
0
0
0
0
0
0
0
0
0
-'4
-'4
code Nos.
ABS
-
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-*2
0
0
05
-
-
-
-
-
-
-
0
self-diagnosis. Lamp
ON
TCS OFF
-
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-
0
When the SLlP
-
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0'5
0
0
0
0
0
0
-
0
malfunction

ELECTRIC SUPER HICAS
Control
Unit Input/Output Signal Specifications
USING CIRCUIT TESTER
Terminal No.
Check item Specification
When control unit is disconnected
: Continuity exists.
Control unit ground circuit
Motor driving output signal
When ignition switch is
ON : Power supply voltage
(In fail-safe mode
: OV)
Motor voltage
When vehicle speed is
0 krn/h : Approx. 4.4 - 6.6V
When vehicle speed is
100 km/h : Approx. 2.4 - 3.6V EPS solenoid driving signal
Battery voltage
I Power supply voltage
Data link connector for CONSULT
(TX) I -
Engine speed signal Measure
tachometer driving signal.
Refer to EC section YECM (TCM) Input/Output Signal
Reference
Value7
.
When ignition switch is ON : Power supply voltage
When ignition switch is OFF
: OV Ignition voltage
Body
/ ground HlCAS waming
lamp When HlCAS warning
lamp is ON
: Approx. OV
When
HlCAS
warning
lamp
is
OFF : Approx. 12V
When ignition switch is ON : Approx. 12V
(In fail-safe mode : Approx. OV)
Output
signal for driving motor relay
Data link connector for CONSULT
(RX) I -
Stop lamp switch signal
(Send brake pedal operation signal to control unit.) When
pedal is depressed : Power supply voltage
When
pedal is not depressed
: OV
Continuity exists.
v Steering angle sensor 2
Steering angle sensor 1
Body
ground When steering wheel
is turned, the voltage changes
between 0 and 5V.
Ground
circuit for rear steering angle sensor
Output signal of rear steering angle sensor
I When neutral : Approx. 2.4V
-
Neutral signal of rear steering angle sensor
When ignition switch is ON
When ignition switch is
OFF
--
When neutral : Appro~. 5V
: Approx. 5V
: Approx. OV Power supply for rear steering angle sensor