1998 NISSAN GT-R ignition

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
CONSULT for Throttle Control Unit Control
System
CONTROL UNIT PART NUMBER
The part number that is shown on the control unit label and CON-
SULT 23790 AA500
SELF-DIAGNOSIS PROCEDURE
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.
sir
Start engine and drive vehicle at approx. 30 kmlh for approx.
1 minute.
Stop vehicle with engine running and touch "START',
Rs
"THROTTLE CONTROL" and "SELF-DIAG RESULTS"
sequentially on the CONSULT screen.
If "START" is touched immediately after engine is started !iIA
or ignition switch is turned on, "THRORLE CONTROL"
may not be displayed on "SELECT
SYSTEM" screen. To a
display "THROTTLE CONTROL", repeat the self-diagnosis
procedure from the beginning.
Self-diagnosis results are displayed on the screen. (Touch 8~ "PRINT" to print out the self-diagnosis results, if necessary.)
If "NO FAIL" is displayed, inspect SLIP indicator lamp, TCS
OFF indicator lamp, and ABS warning lamp. Refer to BR-26.
Perform appropriate inspection from the self-diagnostic results
mode and repair or replace faulty parts.
Start engine and drive vehicle at approx. 30
krn/h for approx.
1 minute to ensure that there is no other malfunction in the
system.
Turn ignition switch OFF to prepare for erasing the trouble
stored in memory.
Start engine and touch "START', "THROTTLE CONTROL",
"SELF-DIAG RESULTS" and "ERASE sequentially on the
CONSULT screen to erase the trouble stored in memory.
If the malfunction stored in memory is not erased, repeat
step
6.
10. Drive vehicle at approx. 30 km/h for approx. 1 minute and then !
confirm that TCS OFF indicator lamp and SLIP indicator lamp
is OFF.

TCSIABS SYSTEM
CONSULT for Throttle Control Unit Control
System (Cont'd)
SELF-DIAGNOSTIC RESULTS MODE
- - Diagnostic item I Diagnostic item is detected when ... I Check item
THROTTLE
POSl
SEN
THROTTLE MOTOR Throttle
position sensor signal output is abnormally high or
continues to stay low for a certain period of time.
I
Throttle motor sensor signal output is abnormally high or con-
tinues to stay low for
a certain period of time. 1 Throttle motor sensor and circuit
Throttle
position sensor circuit
THRTL OPEN TRGET
THROTTLE ACTUATOR
RLY 1 Throttle motor relay is short-circuited.
[SHORT] Circuit
for throttle motor target angle signal (DKR line) is open
or shorted. TCS/ABS control unit
is abnormal.
Circuit for the communication
line between the throttle control
Throttle motor operation
does not accord with the throttle
motor target angle.
Throttle motor and circuit
I
ENGINE START SIG unit
and the TCSIABS control
unit
1 THROTTLE MOTOR
THROlTLE MOTOR RLY
[OPEN]
I Start signal is not correctiy entered due to short.
Overcurrent
is applied to the throttle motor drive circuit. I
Start signal circuit and
ECM-TCM or
ECM
Throttle motor relay is open.
Throttle motor relay and circuit
connector for
NEUTRAL POSl SW
DATA MONITOR PROCEDURE
Refer to CONSULT Instruction Manual for details on data
monitor function.
Turn ignition switch OFF.
Connect CONSULT connector to data link connector for
CON-
SU LT.
Turn ignition switch ON.
Touch "START' on CONSULT screen.
Touch ''THROTTLE CONTROL" on CONSULT screen.
Touch "DATA MONITOR".
Touch "SETTING" to set recording condition.
Touch one key from
"AUTO TRIG", "MANUAL TRIG" and
"SPECIAL", and then touch "LONG
TIME".
With "AUTO TRIG" selected, the data is automatically recorded
if a malfunction occurs during the data monitor. With "SPE-
CIAL" selected, the data is automatically recorded when TCS
is activated.
Touch "ENTER".
Return to
"SELECT MONITOR ITEM" screen and touch "ALL
SIGNALS". Display data monitor.
If necessary, sequentially touch "REC START', "REC STOP",
"DATA DISPLAY", "NUMBER
PRINT'
and "PRINT' to print
out
the data.
Bb38
Parkheutral position switch signal is not correctly entered due
to open or shorted circuit.
--
Neutral position switch circuit
and PNP switch circuit

TCS/ABS SYSTEM
CONSULT for Throttle Control Unit Control
System (Cont'd)
DATA MONITOR MODE -- -
I Select monitor item
Display
I I
THRTL POS SEN [~l l o I n
I All signals
THRTL OPENING
lo] 1 0 I
Selection
from menu
THRTL POS SE2
MI 0 1;
THRL2 OPENING rOl / 0
BATTERY VOLT MI 0 I A
TH OPEN SIG ims]/ 0 I A
TH MOTOR DUTY I"/.] I 0 I A
CLOSED THUSW [ONIOFF]
NEUT POSl SW [ONIOFF]
START SIGNAL
[ONIOFF]
TH OPEN CONT
["I
TCS SIGNAL [ONIOFF] / OIa
TCS FLAG
0
0
0
0
A
A
A
A
TH CLSD LRN
PoNwEqI 0 / A
COMM COND [ONIOFFJ
VOLTAGE
PI I I A
0
Remarks
A
PULSE [ms, Hz, %I
Dispiays throttle position sensor signal voltage.
Displays throttle angle computed based on throttle position
EG
sensor signal voltage.
Displays throttle motor sensor signal voltage.
AT
-
Displays throttle motor angle computed based on throttle
motor sensor signal voltage.
Displays the battery voltage for the control unit.
h
Displays the pulse width of the throttle motor target angle
signal from the
TCSIABS control unit.
lndicates the switch status (ONIOFF) based on the throttle
position sensor signal.
lndicates the switch status (ONIOFF) based on the
parW
neutral position switch signal. lndicates the status (ONIOFF) based on the starter signal.
Displays the throttle motor control target computed by the
control unit based on each input signal.
lndicates the throttle motor drive duty.
lndicates the throttle motor relay status
(ON/OFF).
lndicates ON when the throttle motor angle reaches a
specified
iower limit.
lndicates "VALID" when throttle motor target angle signal is
received from the
TCS/ABS control unit and the throttle
control unit closes the throttle motor.
lndicates the condition of the communication between
TCS/
ABS control unit and throttle control unit. Normally ON is
indicated, and OFF is shown when there is failure.
lndicates
if the throttle motor has been fully closed before.
"DONE" is indicated when it has, and
"YET" is shown when
it has not yet.
lndicates the voltage measured with a voltage probe.
lndicates the pulse measured with a pulse probe.
If it cannot be measured,
"%" is shown on the display. The
%" mark is also shown to the left of the final data until the
measuring result is output.
I ACTIVE TEST PROCEDURE
1. Turn ignition switch OFF.
2. Connect CONSULT connector to data link connector for CON-
S U LT.
3. Turn ignition switch ON.
4. Touch "START" on CONSULT screen.
5. Touch "THROTTLE CONTROL" on CONSULT screen.

TCSfABS SYSTEM
Self-diagnosis for Throttle Control Unit Control
System
SELF-DIAGNOSIS PROCEDURE
1. Turn ignition switch ON or start the engine to start self-diagnosis. g 2. The control unit LED comes on to indicate the malfunction code No.
3. Verify the location of the malfunction with "MALFUNCTION CODEISYMPTOM CHART", BR-42. Then
make the necessary repairs.
4. After the malfunctions are repaired, erase the malfunction codes stored in the control unit. Refer to "HOW EC
TO ERASE SELF-DIAGNOSTIC RESULTS" shown below.
5. Turn ignition switch OFF and then turn ignition switch ON or start the engine to verify that the malfunction AT
codes have been erased.
6. Verify that SLIP indicator lamp and TCS indicator lamp are OFF.
HOW TO READ SELF-DIAGNOSTIC RESULTS (Malfunction codes)
p
Determine the code No. by observing the time and the frequency that the throttle control unit LED blinks
ON and OFF. When multiple malfunctions occur at a time, all the code numbers can be stored. The indi-
cation begins with the start code
No. 12, followed by the stored malfunction codes. The smallest number
of the stored codes appears first and the others follow sequentially. The indication then returns to the start RS code No. 12 to repeat.
The malfunction code No. 55 is only indicated repeatedly when there is no malfunction.
P L / L -Z Code No. 12 Code No. 33 Unit: seconds BR90025D
Example: Code No. 12 and No. 33
0.6 0.3 0.6 0.3
HOW TO ERASE SELF-DIAGNOSTIC RESULTS (Malfunction codes)
I. With the throttle fully open, turn the neutral position switch OFF (or a position other than P and N).
2. Turn ignition switch-ON without starting the-engine. Then, turn the pa;k/neutral position switch ON (or P
or N} and release the acceleration pedal.
As for the following items, self-diagnostic results can be erased if the conditions in the chart are met. In
this case the steps above are not necessary.
(tens digit) '
ON
OFF
Malfunction code
No.
1-1-t-r- =i i 0.9 0.3 3.3 0.6 0.9-1 -' 3.3 To be repeated
-
\5
'c - (units digit) -1-
-
Malfunctioning part
Start signal circuit
-
Condition
Circuit for the communication line
(DKR line) between
the TCS control unit and the throttle control unit
The start signal is detected next time the ignition
switch is turned ON.
LCIW
-
Normal communication synchronicity is achieved.
ParWneutral
position switch circuit
dbr I
ParWneutral position switch operation is detected next
time the ignition switch is turned
ON.
- - -
--.

ELECTRIC SUPER HICAS
INSPECTION BEFORE DRIVING
Check fluid leakage from power steering components (gear, pump, piping, etc.), and check whether the
fluid level is within the proper range.
Check whether tire size and inflation pressure are within the specified limits. Check also whether the
steering wheel is a genuine part, and whether a non-genuine control unit is attached.
Check whether wheel alignment is within the specified limits.
Check whether suspension system is modified, and whether the modification, if any, has increased the
vehicle weight.
INSPECTION DURING DRIVING
Check facts about trouble (what, when, where, who, why and how).
Check whether the engine is running in good condition.
System Description
This system contains two functions for SUPER HICAS: self-diagnosis function and fail-safe function.
For self-diagnosis function, refer to "SELF-DIAGNOSIS PROCEDURE on pages ST-7 and
ST-12.
FAIL-SAFE FUNCTION
If the system detects some error, it halts the normal control and enters the fail-safe mode.
In this event, the system notifies the driver of a malfunction by turning ON the HICAS warning lamp.
The fail-safe mode is canceled when ignition switch
is turned OFF. If, however, the fail-safe mode is caused
by a vehicle speed signal error, it is automatically canceled when the signal is restored before the ignition
switch is turned OFF.
HICAS WARNING LAMP
When the system is in normal condition, HICAS warning lamp is turned ON by switching the ignition ON, and
is turned OFF after engine has started.

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

ELECTRIC SUPER HlCAS
Control Unit
Input/Output Signal Specifications
(Cont'd)
USING CONSULT
The displayed output signals represent the control unit com-
puted data. If the output circuit (harness) should
be open,
correct values may be displayed.
Monitor item
VHCL SPEED SE
[km/hj
STOP LAMP SW
[ON-OFF] Data monitor
I Condition
Specification
--
STEERING ANG Steering
wheel is turned right Steering angle (degrees) mea-
[R/Ll or left. sured from neutral position
NEUTRAL SIG Steering wheel is in neutral When neutral: ON
[ON-OFF] position
or turned right or left. When
turned (right or left): OFF
Brake pedal operation Check
item
Vehicle is running or driving
wheels are turning.
Steering angle sensor circuit
Approximately
equal to speed-
ometer reading
When pedal is depressed: ON
When pedal is not depressed:
I OFF
In neutral position:
Approx.
2.4V Vehicle
speed sensor circuit
Stop lamp switch circuit
ENGINE SPEED
[r~ml
1"l I Actuator is operating in active I In right lock position:
test. Engine
is running.
Approx. 4.4V
in left lock position:
Approx.
0.4V
Rear steering angle sensing
system
Approximately
equal to tachom-
eter reading
POWER STR SOL
[A1
Wiring
in ECM-HICAS control
unit
MOTOR CURRENT
PI
Vehicle speed is changed from
0 to 100 krnh.
HlCAS RELAY
[ON-OFF]
FAILSAFE
[ON-OFF] At
0 km/h:
Approx. 1.1 0A
At
100 krn/h: Approx. 0.48A
WARNING LAMP
[ON-OFF] System related to power steer-
ing solenoid output signal
RR ST
ANG-VOL
[Vl
MOTOR VOLTAGE
[vl
Actuator is operating in active
test.
Ignition switch is ON or engine
is running.
I Power supply system for
OK
if output current is detected
during operation Motor
and its power supply
system
1 signal from control unit
When ignition
switch is ON: ON
Not in operation HICAS
motor relay
System related to relay driving
Check malfunctioning parts
using self-diagnosis and data
monitor.
Approx.
5V
When warning lamp is ON: ON
When warning lamp is OFF:
OFF
Rear steering angle sensing
system Warning
lamp circuit
Power supply voltage Motor power
supply system
C/U
VOLTAGE
[VI Control unit power supply cir-
cuit
Ignition
switch is ON or engine
is running. Power
supply voltage