BRC-6
[4WD/ABS]
ALL MODE 4X4 SYSTEM
ALL MODE 4X4 SYSTEM
PFP:47850
System DescriptionEFS001CJ
ABS FUNCTION
●During ABS operation, brake pedal lightly vibrates and its mechanical noise may be heard. This is a nor-
mal condition.
●When starting engine, or just after starting vehicle, brake pedal may vibrate. Also motor operating noise
may be heard from engine compartment. This is a normal status of operation check.
● When vehicle drives on rough, gravel, or snowy (fresh deep snow) road, the following conditions occur.
Stopping distance may be longer than that of vehicles without ABS.
4WD FUNCTION
● Electronically controlled 4WD is controlled by the same control module as that for ABS (4WD/ABS control
unit). 4WD/ABS control unit controls both electronically-controlled 4WD and ABS, based on input signals
from several sensors.
●If electrical system-related malfunction occurred in 4WD/ABS system, control unit illuminates the following
lamps: 4WD warning lamp and/or ABS warning lamp on meter control unit assembly. This notifies driver of
malfunction. At the same time, control unit indicates malfunctioning part detected by self-diagnosis with
flashing pattern of LED. Indication on electronic system diagnosis tester (CONSULT) corresponds to this
flashing pattern as shown below.
Control System DiagramEFS001CK
Self-diagnostic test mode Remarks
Result of self-diagnosis Conformable to 4WD/ABS
Data monitor Conformable to 4WD/ABS
Active testChecks ABS solenoid valve ON/OFF, ABS motor ON/OFF, 4WD sole-
noid
Control unit part No. 4WD/ABS control unit
SFIA0350E
TROUBLE DIAGNOSIS
BRC-7
[4WD/ABS]
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BRC
TROUBLE DIAGNOSISPFP:00004
Fail-safe FunctionEFS001BB
●If a malfunction occurs in 4WD/ABS electrical system, and control unit detects the malfunction, 4WD
warning light on gauge turns ON to inform driver of system malfunction.
●When 4WD and ABS warning lamp is ON, vehicle is in 2WD.
How to Proceed with Trouble DiagnosisEFS001BC
BASIC CONCEPT
●The most important point to perform trouble diagnosis is to understand vehicle systems (control and
mechanism) thoroughly.
●It is also important to clarify customer complaints before inspec-
tion.
First of all, reproduce symptom, and understand it fully.
Ask customer about his/her complaints carefully. In some cases,
it will be necessary to check symptoms by driving vehicle with
customer.
CAUTION:
Customers are not professional. It is dangerous to make an
easy guess like “maybe the customer means that...,” or
“maybe the customer mentions this symptom”.
●It is essential to check symptoms right from the beginning in
order to repair a malfunction completely.
For intermittent malfunction, reproduce symptom based on inter-
view with customer and past examples. Do not perform inspec-
tion on ad hoc basis. Most intermittent malfunctions are caused
by poor contacts. In this case, it will be effective to shake sus-
pected harness or connector by hand. When repairing without
any symptom diagnosis, you can not judge if malfunction has
actually been eliminated.
●After completing diagnosis, always erase diagnostic memory.
Refer to BRC-24, "
Operation Procedure" .
●For intermittent malfunction, move harness or harness connector by hand. Then check poor contact or
false open circuit.
●Always read “GI General Information” to check general to confirm general precautions.
SEF234G
SEF233G
TROUBLE DIAGNOSIS
BRC-19
[4WD/ABS]
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BRC
CAUTION:
1. Light tight-corner braking symptom may occur depending on driving conditions in AUTO mode.
This is not malfunction.
2. Heavy tight-corner braking symptom occurs when vehicle is driven in the following conditions:
LOCK mode, steering wheel is turned fully to either sides, and accelerator pedal was depressed.
4WD/ABS Control Unit Input/Output Signal StandardEFS001BG
4WD/ABS CONTROL UNIT CONNECTOR TERMINAL ARRANGEMENT
CAUTION:
When ignition switch is turned to ON with connectors of 4WD/ABS control unit and actuator con-
nected.
REFERENCE STANDARD TABLE
Specifications defined by circuit tester
Vehicle running, 4WD warning lamp
flashes slowly. (When it flashes for
Approx. One minute, then does not illu-
minate.) slow flashing: One flashing
per 2 seconds●Engine run-
ning
●Driving at
vehicle speed
30km/h (19
MPH)Tire size is different for front and rear of vehicle.BRC-45
Vehicle does not enter 4WD mode
even though 4WD warning lamp is off.Engine runningMechanical malfunction of electronically con-
trolled coupling (Mechanical engagement of
clutch is not possible.)BRC-46
Symptom Condition Check items Reference page
SFIA0351E
Te r m i n a l N o .
Location Standard (note 1)(Note) Check
points when result
was malfunctioning +–
3.
109Power supply Ignition switch ONB a t t e ry v o lta g e ( A p p ro x .
12V)Control unit power
supply circuit
BRC-30
[4WD/ABS]
TROUBLE DIAGNOSIS
ABS motor
Touch “ON” and “OFF” on screen. Check ABS motor relay operates
as shown in the following chart.
NOTE:
●If active test is performed with brake pedal depressed, pedal
stroke may be changed. This is a normal condition.
●“TEST STOP” is displayed 10 seconds later from the operation
start.
Active test
4WD solenoid valve
Under the vehicle stopped with engine running, touch UP, DOWN on
screen. Adjust 4WD solenoid command current.
Check the monitor current at that time. If monitor current is within
Approx. ±10%, light switch is normal.
CAUTION:
Do not continuously energize solenoid for long period of time.
Component InspectionEFS001BJ
ABS ACTUATOR
●Disconnect each ABS actuator E69, E70, E71 connector. Con-
firm continuity and resistance value between each pair of ABS
actuator-side terminal.
CAUTION:
Be sure ABS motor is securely grounded.
Operation ON OFF
ABS actuator ON ON
ABS motor ON OFF
SFIA0397E
SDIA0626E
SFIA1099E
TROUBLE DIAGNOSIS
BRC-31
[4WD/ABS]
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Continuity Exists, Resistance Value
Insulation Inspection
●Check resistance value between each pair of ABS solenoid connector E71 terminal No.6 and E70 and
E71 terminals No.1, 2, 3,12, 25, 26, 27, 28.
ABS Motor Operation Inspection
1. Connect 2-pin connector on ABS actuator harness connector
E69 terminals No. 9 (R/B) and No. 10 (Y).
2. Apply voltage of Approx. 12V voltage between connector E70
terminal No. 5 and E70 terminal No. 8 on ABS relay unit. Mea-
sure motor voltage (E70 terminal No. 4 - Body ground) using an
oscilloscope and check motor counter electromotive force dura-
tion when operation stops.
CAUTION:
●Before measuring time, check each part of ABS relay unit
and confirm motor relay is normal.
●To prevent overheating, ABS motor should be driven no
longer than 4 seconds.
●Motor counter electromotive force duration is based on the
time at 20°C, in ambient temperatures, with 12V battery volt-
age. If battery voltage is low, time will be slightly shorter.
SFIA0930E
Standard : 5.8 - 21.2 Ω
Motor counter electromotive force duration:
0.1 second or longer
SFIA0931E
BRC-40
[4WD/ABS]
TROUBLE DIAGNOSIS
2. CHECK USING THE DATA MONITOR FUNCTION OF THE CONSULT- II
●Perform inspection by the data monitor function of the CONSULT-II.
●Check that the operation is in AUTO mode.
●Measure voltage when the accelerator pedal is not depressed. (Accelerator pedal not depressed: Approx.
0.5V or lower)
●Measure the current supplied to the E-TS solenoid valve. (Accelerator pedal not depressed: Approx. 0A)
OK or NG
OK >> GO TO 3. (No self-diagnosis malfunction indicated.)
NG >>
●Not in AUTO mode. GO TO 3.
●Voltage when accelerator pedal is not depressed is higher than approximately 0.5V.
●4WD solenoid valve current when the accelerator pedal is not depressed is other than 0A.
●Countermeasure: Keep the vehicle idling for approximately 15 minutes before checking again.
(Voltage when accelerator pedal is not depressed will be automatically reset to zero during this
period.)
3. INSPECTION USING 4WD MODE CHANGE-OVER SWITCH
●On data monitor screen of the CONSULT-II, check 4WD mode switch.
●Check if the display changes from ## to 2WD mode when the 2WD switch is pressed.
●Check if the display changes from ## to AUTO mode when the AUTO switch is pressed.
●Check if the display changes from ## to LOCK mode when the LOCK switch is pressed.
OK or NG
OK >> No malfunction detected.
NG >>
●Not in AUTO mode. (In 2WD or LOCK mode)
Countermeasure: Slightly depress the accelerator pedal and check that the operation mode
changes to LOCK mode.
●Check circuit between 4WD mode switch harness connector M39 terminal No.1 (BR) and
4WD control unit harness connector E122 terminal No. 27 (BR).
(AUTO mode is not available because a malfunction is present in the 2WD mode harness.)
NOTICE:
Mechanism of 4WD mode change-over
●2WD mode: Operation changes to 2WD mode when 4WD/ABS control unit harness connector
E122 terminal No. 27 (BR) is shorted to ground.
●AUTO mode: Operation changes to AUTO mode when 4WD/ABS control unit harness connec-
tor E122 terminals No. 27 (BR) and No. 26 (L) is shorted to ground.
●LOCK mode: Operation changes to LOCK mode when 4WD/ABS control unit harness connec-
tor E122 terminal No. 26 (L) is shorted to ground.
TROUBLE DIAGNOSIS
BRC-45
[4WD/ABS]
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BRC
3.INSPECTION USING DRIVE MODE CHANGE-OVER SWITCH
●On data monitor screen of the CONSULT, check 4WD mode switch.
●Check if the display changes from ## to 2WD mode when the 2WD switch is pressed.
●Check if the display changes from ## to AUTO mode when the AUTO switch is pressed.
●Check if the display changes from ## to LOCK mode when the LOCK switch is pressed.
Is inspection result OK?
YES >> No malfunction detected.
NO >>
●Not in AUTO mode. (In 2WD or LOCK mode)
Countermeasure: Slightly depress the accelerator pedal and check that the operation mode
changes to LOCK mode.
●Check path between drive mode switch and 4WD/ABS control unit E122 terminal No.27 (BR).
(AUTO mode is not available because a malfunction is present in the 2WD mode harness.)
NOTICE:
Mechanism of drive mode change-over
●2WD mode: Operation changes to 2WD mode when 4WD/ABS control unit connector terminal
No. 27 is shorted to ground.
●AUTO mode: Operation changes to AUTO mode when 4WD/ABS control unit connector termi-
nals No. 27 and No. 26 were shorted to ground.
●LOCK mode: Operation changes to LOCK mode when 4WD/ABS control unit connector E122
terminal No. 26 (L) is shorted to ground.
Drive Modes Cannot Be Switched After Engine Is Started.EFS001BU
1.INSPECTION USING DRIVE MODE CHANGE-OVER SWITCH
●Drive modes cannot be switched after the engine is started.
●On data monitor screen of the CONSULT, check 4WD mode switch.
●Check if the display changes from ## to 2WD mode when the 2WD switch is pressed.
●Check if the display changes from ## to AUTO mode when the AUTO switch is pressed.
●Check if the display changes from ## to LOCK mode when the LOCK switch is pressed.
Is inspection result OK?
YES >> No malfunction detected.
NO >>
●CONSULT-II display does not change from ## when the 2WD switch is pressed. Check harness
of the 2WD switch.
●CONSULT-II display does not change from ## when the AUTO switch is pressed. Check har-
ness of the 2WD switch and LOCK switch.
●CONSULT-II display does not change from ## when the LOCK switch is pressed. Check har-
ness of the LOCK switch.
●Perform drive mode change-over switch inspection.
Wheel Driving, 4WD Warning Lamp Flashes Rapidly. (When It Flashes For
Approx. One Minute, Then Does Not Illuminate.)
EFS001BV
●Wheel driving, 4WD warning lamp flashes rapidly. (When it flashes for Approx. 1 minute, then does not
illuminate.)
Rapid flashing: 2 times/second
This phenomenon protects drivetrain parts when a heavy load is applied to the electronically controlled
coupling and multiple disc clutch temperature increases. It is not a malfunction.
Wheel Driving, 4WD Warning Lamp Flashes Slowly. (When It Continues To Illu-
minate Until Engine Turns OFF.)
EFS001BW
1. Check using the data monitor function of the CONSULT-II.
●Perform inspection with the data monitor function of the CONSULT-II.
●Check if the value of IMPROPER SIZE TIRE MONITOR is 8 mm or more.
BRC-54
[ESP/TCS/ABS]
PRECAUTIONS
[ESP/TCS/ABS]PRECAUTIONSPFP:00001
Precautions for Brake SystemEFS0019O
●Recommended fluid is brake fluid “DOT 3” or “DOT 4”.
●Never reuse drained brake fluid.
●Be careful not to splash brake fluid on painted areas; it may cause paint damage. If brake fluid is splashed
on painted areas, wash it away with water immediately.
●Never use mineral oils such as gasoline or kerosene. They will ruin rubber parts of hydraulic system.
●Use flare nut wrench when removing and installing brake tubes.
●Always torque brake lines when installing.
●Before working, turn the ignition switch OFF and disconnect the
connectors for the ESP/TCS/ABS actuator and control unit or
the battery terminals.
●Burnish the brake contact surfaces after refinishing or replacing
drums or rotors, after replacing pads or linings, or if a soft pedal
occurs at very low mileage. Refer to BR-10, "
Brake Burnishing
Procedure" .
WARNING:
Clean brakes with a vacuum dust collector to minimize risk
of health hazard from powder caused by friction.
Precautions for Brake ControlEFS0019P
●During the ESP/TCS/ABS operation, the brake pedal vibrates lightly and its mechanical noise may be
heard. This is a normal condition.
●Just after starting the vehicle after ignition switch ON, the brake pedal may vibrate or the motor operating
noise may be heard from the engine compartment. This is a normal status of the operation check.
●The stopping distance may be longer than that of vehicles without ABS when the vehicle drives on rough,
gravel, or snowy (fresh deep snow) road.
●If a malfunction is indicated by the ABS warning lamp, or other warning lamps, collect the necessary infor-
mation from the customer (what symptoms are present under what conditions) and find out the possible
causes before starting the service. Besides the electrical system inspection, check the booster operation,
brake fluid level, and oil leaks.
●If the tire size and type are used in a improper combination, or the brake pads are not NISSAN genuine
parts, the stopping distance or steering stability may deteriorate.
●If there is a radio, antenna, or antenna lead-in wire (including wiring) near the control unit, the ESP/TCS/
ABS function may have a malfunction or error.
●If aftermarket parts (e.g. Car stereo equipment, CD player) have been installed, check the electrical har-
nesses for pinches, open, and improper wiring.
Precautions for CAN SystemEFS001CP
FOR INSPECTION
●Do not apply voltage of 7.0V or higher to the measurement terminals.
●Use the tester with its open terminal voltage being 7.0V or less.
●Before harness inspection, turn the ignition switch off, disconnect the negative battery terminal.
SBR820BA