traction control NISSAN X-TRAIL 2003 Service Repair Manual

SYSTEM DESCRIPTION
BRC-53
[ESP/TCS/ABS]
C
D
E
G
H
I
J
K
L
MA
B
BRC

3. During TCS operation, it informs a driver of system operation by flashing SLIP indicator lamp.
CAUTION:

During TCS operation, body and brake pedal lightly vibrate and the mechanical noise may be
heard. This is a normal condition.

Depending on road circumstances, a driver may have a sluggish feel. This is not abnormal,
because the optimum traction has the highest priority by TCS operation.

When the vehicle is passing through a road where the surface friction coefficient varies, down-
shifting or depressing the accelerator pedal fully may activate TCS temporarily.
ABS FunctionEFS0019U
1. In cases of braking suddenly or braking on slippery road (ice road), ABS functions prevent wheels from
lock, improve the stability in sudden braking, and make efficient avoidance of obstacles with steering
manipulation by detecting wheel speed and controlling brake fluid pressure.
2. EBD is integrated in ESP/TCS/ABS system.
CAUTION:

During ABS operation, brake pedal lightly vibrates and its mechanical noise may be heard. This is
a normal condition.

When starting engine, or just after starting vehicle, brake pedal may vibrate or the motor operating
noise may be heard from engine compartment. This is a normal status of the operation check.

The stopping distance may be longer than that of vehicles without ABS when vehicle drives on
rough, gravel, or snowy (fresh deep snow) road.
EBD FunctionEFS004HO

Electronic Brake Distributor is a function that detects subtle slippages between front and rear wheels dur-
ing braking, and it improves handling stability by electronically controlling the brake fluid pressure which
results in reduced rear wheel slippage.

In case of electrical system break down, the fail-safe function is activated, EBD and ABS becomes inoper-
ative, and ABS warning lamp and brake warning lamp are turned on.

Electrical System Diagnosis by CONSULT-II is available.
Fail-Safe FunctionEFS004HP
ESP/ TCS SYSTEM
In case of throttle control system trouble, ESP OFF indicator lamp and SLIP indicator lamp are turned on, and
the condition of vehicle is the same as the condition of vehicles without ESP/TCS equipment. In case of trou-
ble to the throttle control system, the ABS control continues to operate normally without ESP/TCS control.
CAUTION:
If the fail-safe function is activated, then perform the self- diagnosis for ESP/TCS/ABS control system.
ABS, EBD SYSTEM
In case of electrical malfunctions with the ABS, ABS warning lamp, ESP OFF indicator lamp and SLIP indica-
tor lamp will turn on. In case of electrical malfunctions with the EBD, brake warning lamp, ABS warning lamp,
ESP OFF indicator lamp and SLIP indicator lamp will turn on. Simultaneously, the ESP/ TCS/ABS become one
of the following conditions of the fail-safe function.
1. For ABS trouble, only the EBD is activated and the condition of vehicle is the same condition of vehicles
without ESP/TCS/ABS equipment.
2. For EBD trouble, the EBD and ABS become inoperative, and the condition of vehicle is the same as the
condition of vehicles without ESP/TCS/ABS, EBD equipment.
NOTE:
In condition 1 described above, an ABS self-diagnosis sound may be heard. That is a normal condition
because a self-diagnosis for “Ignition switch ON” and “The first starting” are being performed.

BRC-86
[ESP/TCS/ABS]
TROUBLE DIAGNOSIS

For Fast and Accurate DiagnosisEFS004H8
PRECAUTIONS FOR DIAGNOSIS

Before performing diagnosis, always read precautions. Refer to BRC-58, "How to Proceed With Diagno-
sis" .

If ESP/TCS/ABS control unit steering angle sensor, steering system parts or suspension system parts
have been replaced, or if alignment has been adjusted, be sure to adjust neutral position of steering angle
sensor before driving. Refer to BRC-51, "
Adjustment of Steering Angle Sensor Neutral Position" .

After diagnosis is finished, be sure to erase memory. Refer to BRC-79, "SELF-DIAGNOSIS" .

When checking continuity and voltage between units, be sure to check for disconnection, looseness,
bend, or collapse of connector terminals. If any malfunction is found, repair or replace connector termi-
nals.

For intermittent symptoms, possible cause is malfunction in harness, harness connector, or terminals.
Move harness, harness connector, and terminals to check for poor connections.

If a circuit tester is used for the check, be careful not to forcibly extend any connector terminal.

To use CONSULT-II to perform self-diagnosis of ESP/TCS/ABS control unit active tests, or work support,
first stop work, then connect CONSULT-II and select “ABS”.

While self-diagnostic results of CONSULT-II shows malfunction, if CONSULT-II active test is performed,
an engine system error may be indicated. In this case, start engine to resume the normal screen.

ESP/TCS/ABS system electronically controls brake operation and engine output. The following symptoms
may be caused by normal operations:
Symptom Symptom description Result
Motor operation noiseThis is noise of motor inside ESP/TCS/ABS control unit. Slight noise
may occur during ESP, TCS, and ABS operation.
Normal
When the vehicle speed goes over 20 km/h (12.5 MPH), motor and
valves operating noise may be heard. It happens only once after IGN
(ignition) is ON. This is a normal status of the system operation check.
System operation check
noiseWhen engine starts, slight “click” noise may be heard from engine room.
This is normal and is part of system operation check.Normal
ESP/TCS operation
(SLIP indicator lamp blink-
ing)TCS may activate momentarily if wheel speed changes when driving
over location where friction coefficient varies, when up/downshifting, or
when fully depressing accelerator pedal.
Normal
Cancel the ESP/TCS
function for the
inspection on a chas-
sis dynamometer. For inspection of speedometer or other instruments, press ESP OFF
SW to turn ESP/TCS function off.
When accelerator pedal is depressed on a chassis dynamometer (fixed
front-wheel type), vehicle speed will not increase. This is not normal. It is
result of TCS being activated by stationary front wheels. Warning lamp
may also illuminate to indicate “sensor system error”. This is also nor-
mal, and is the result of the stationary front wheels being detected. To be
certain, restart engine, and drive vehicle at 30 km/h (19 MPH) or more.
Make sure warning lamp does not illuminate.
ABS operation (Longer stop-
ping distance)On roads with low friction coefficients, such as snowy roads or gravel
roads, vehicles with ABS may require a longer stopping distance. There-
fore, when driving on such roads, avoid overconfidence and keep speed
sufficiently low.Normal
Insufficient feeling of accel-
erationDepending on road conditions, driver may feel that feeling of accelera-
tion is insufficient. This is because traction control, which controls
engine and brakes to achieve optimal traction, has the highest priority
(for safety). As a result, there may be times when acceleration is slightly
less than usual for the same accelerator pedal operation.Normal