1998 NISSAN GT-R check engine light

TCSIABS SYSTEM
System
Description
ABS FUNCTION
During ABS operation, the brake pedal pulsates along with a mechanical noise. This ensures that the ABS
is working properly. mP
When starting up the engine or immediately after the vehicle starts to run, the brake pedal pulsates and G'
a motor noise from the engine compartment can be heard. They are caused by the ABS operation check
and should not be considered abnormal.
A vehicle with the ABS may stop in a longer distance than a vehicle without the ABS when the brake is
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applied on a bad road, gravel road, or deep fresh snow.
TCS FUNCTION
TCS/ABS control unit monitors the speed of the driving wheels through 4 wheel speed sensors. If driving
wheel slip is detected, fuel to the engine is cut
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and the throttle valve is adjusted so that the engine
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torque is reduced. On vehicles with automatic transmission, transmission shift schedule is also changed
to control the rear wheel driving torque, which results
in the reduction of wheel slip. This system enables
the throttle valve to be controlled so that optimum engine torque can be achieved in accordance with the
driver's acceleration request.
The driver may not feel satisfied with acceleration on some road surfaces. This poor acceleration occurs
because the operating TCS gives priority to maintaining optimum traction. Therefore, this condition should
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be considered normal.
When shiftdown is made or the acceleration pedal is depressed while the vehicle is driven on the road
surface that has different friction coefficients, the TCS may operate temporarily.
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On vehicles with manual transmission, the SLlP indicator lamp and the TCS OFF indicator lamp may light
up when the engine is about to stall in the conditions shown below.
If the lamps go off when engine speed
increases, there is no problem in the system.
At start, the engine almost stalls and the engine speed is much lower than the idle speed.
The vehicle is driven at an extremely low speed with a high-speed gear engaged.
The clutch has been engaged until the vehicle almost stops. 8D
FAIL-SAFE FUNCTION
ABS system
If any malfunction is detected in the system, the ABS warning lamp, the TCS OFF indicator lamp and the SLlP
indicator lamp in the instrument panel is turned on with the TCSIABS deactivated and the vehicle's brake sys-
tem reverts to normal operation.
TCS system
If any malfunction is detected in the system, both the SLlP indicator lamp and the TCS indicator lamp on the
instrument panel light up and the TCS is shut down. The vehicle operates in the same manner as a vehicle
without the
TCS, while the ABS is operational.
If there is a malfunction in the throttle control system, the TCS becomes inoperative while the ABS
remains functional.
When fail-safe operation is activated, perform the self-diagnosis procedure for the TCSIABS first.
Refer to
BR-27 for details.

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.