wheel SUZUKI GRAND VITARA 1999 2.G Service Manual

ANTILOCK BRAKE SYSTEM (ABS) 5E2-3
General Description
Components/Parts Location
The ABS (Antilock Brake System) controls the fluid pressure applied to the wheel cylinder of each brake from
the master cylinder so that each wheel is not locked even when hard braking is applied.
This ABS has also the following function.
While braking is applied, but before ABS control becomes effective, braking force is distributed between the
front and rear so as to prevent the rear wheels from being locked too early for better stability of the vehicle.The
main component parts of this ABS include the following parts in addition to those of the conventional brake sys-
tem.
Wheel speed sensor which senses revolution speed of each wheel and outputs its signal.
ABS warning lamp which lights to inform abnormality when system fails to operate properly.
ABS hydraulic unit/control module assembly is incorporated ABS control module, ABS hydraulic unit (actua-
tor assembly), fail-safe relay and pump motor relay.
–ABS control module which sends operation signal to ABS hydraulic unit to control fluid pressure applied to
each wheel cylinder based on signal from each wheel speed sensor so as to prevent wheel from locking.
–ABS hydraulic unit which operates according to signal from ABS control module to control fluid pressure
applied to wheel cylinder of each 4 wheels.
–Fail-safe relay (solenoid valve) relay which supplies power to solenoid valve in ABS hydraulic unit and
pump motor relay.
–Pump motor relay which supplies power to pump motor in ABS hydraulic unit.
G sensor which detects body deceleration speed. (For 4WD model only)
This ABS is equipped with Electronic Brake force Distribution (EBD) system that controls a fluid pressure of rear
wheels to best condition, which is the same function as that of proportioning valve, by the signal from wheel sen-
sor independently of change of load due to load capacity and so on. And if the EBD system fails to operate prop-
erly, the brake warning lamp lights to inform abnormality.
1. Wheel speed sensor (Right-front) 6. Wheel speed sensor (Left-rear) 11. G sensor (For 4WD model only)
2. Stop lamp switch 7. Ground 12. Wheel speed sensor rotor (ring)
3. Data link connector 8. Diagnosis connector (Black connector) 13. 4WD switch (For 4WD model only)
4.“ABS” warning lamp 9. Wheel speed sensor (Left-front) 14. EBD warning lamp (Brake warning lamp)
5. Wheel speed sensor (Right-rear) 10. ABS hydraulic unit/control module assembly
(with ABS pump motor relay and fail-safe relay)
NOTE:
Above figure shows left-hand steering vehicle.
For right-hand steering vehicle, parts with (*) are installed at the side of symmetry.

ANTILOCK BRAKE SYSTEM (ABS) 5E2-5
Diagnosis
To ensure that the trouble diagnosis is done accurately and
smoothly, observe “PRECAUTIONS IN DIAGNOSING TROU-
BLES” and follow “ABS DIAGNOSTIC FLOW TABLE”.
Precautions in Diagnosing Troubles
If the vehicles was operated in any of the following ways,
ABS warning lamp may light momentarily but this does not
indicate anything abnormal in ABS.
–The vehicle was driven with parking brake pulled.
–The vehicle was driven with brake dragging.
–The vehicle was stuck in mud, sand, etc.
–Wheel spin occurred while driving.
–Wheel(s) was rotated while the vehicle was jacked up.
Be sure to read “PRECAUTIONS FOR ELECTRONIC CIR-
CUIT SERVICE” in Section 0A before inspection and
observe what is written there.
Be sure to use the trouble diagnosis procedure as described
in the flow table. Failure to follow the flow table may result in
incorrect diagnosis. (Some other diagnosis trouble code may
be stored by mistake in the memory of ABS control module
during inspection.)
When disconnecting ABS hydraulic unit/control module con-
nector (1), pull up lock (2) of connector.
When connecting, set the connector on ABS hydraulic unit/
control module assembly and push the lock (2) down.
D : Disconnect
C : Connect

5E2-10 ANTILOCK BRAKE SYSTEM (ABS)
Diagnostic Trouble Code (DTC) Check (Using
ABS Warning Lamp)
1) Perform ABS WARNING LAMP CHECK described above.
2) Using service wire (4), connect diagnosis switch terminal (2)
of monitor coupler (1) to ground (3).
3) Turn ignition switch ON.
4) Read flashing of ABS warning lamp which represents DTC
as shown in example below and write it down. When more
than 2 DTCs are stored in memory, flashing for each DTC is
repeated three times starting with the smallest DTC number
in increasing order.
For details of DTC, refer to “DTC TABLE”.
Example : When right-front wheel speed sensor circuit opens (DTC 21)
5) After completing the check, turn ignition switch off, discon-
nect service wire from monitor coupler.

5E2-12 ANTILOCK BRAKE SYSTEM (ABS)
4) Repeat disconnecting and reconnecting of service wire
between diagnosis and ground terminals 5 times or more at
about 1sec. interval within 10 seconds.
5) Turn ignition switch OFF and disconnect service wire from
monitor coupler.
6) Perform “DRIVING TEST” (Step 2 of “ABS DIAGNOSTIC
FLOW TABLE” in this section) and “DTC CHECK” and con-
firm that normal DTC (DTC 12) is displayed ; not malfunction
DTC.
Diagnostic Trouble Code (DTC) Table
O : Open
S : Short
T : About 10 seconds
NOTE:
It is also possible to clear DTC by using SUZUKI scan
tool. Refer to Cartridge Manual for procedure to clear
DTC.
CAUTION:
Be sure to perform “ABS DIAGNOSTIC FLOW TABLE” before starting diagnosis.
DTC
(displayed
on SUZUKI
scan tool)DTC
(indicated by
ABS warning
lamp)ABS warning lamp flashing
patternDIAGNOSTIC ITEMS
NO DTC 12 Normal
C1015 15 G sensor circuit and 4WD lamp circuit
C1021 21 RF
Wheel speed sensor circuit C1025 25 LF
C1031 31 RR
C1035 35 LR

ANTILOCK BRAKE SYSTEM (ABS) 5E2-13
C1022 22 RF
Wheel speed sensor circuit
or sensor ring C1026 26 LF
C1032 32 RR
C1036 36 LR
C1041 41
RFInlet solenoid valve circuit
C1042 42 Outlet solenoid valve circuit
C1045 45
LFInlet solenoid valve circuit
C1046 46 Outlet solenoid valve circuit
C1055 55
REARInlet solenoid valve circuit
C1056 56 Outlet solenoid valve circuit
C1057 57 Power source
C1061 61 ABS pump motor and/or motor relay circuit
C1063 63 Fail safe-relay
C1071 71 ABS control moduleDTC
(displayed
on SUZUKI
scan tool)DTC
(indicated by
ABS warning
lamp)ABS warning lamp flashing
patternDIAGNOSTIC ITEMS

5E2-14 ANTILOCK BRAKE SYSTEM (ABS)
System Circuit
1. Battery 11. ABS fail-safe transistor (Solenoid valve transistor) 21. To ECM and SDM (if equipped)
2. Main fuses 12. ABS pump motor transistor 22. Stop lamp
3. Ignition switch 13. Pump motor 23. Stop lamp switch
4. Circuit fuses 14. Solenoid valves 24. G sensor (For 4WD vehicle only)
5. Combination meter 15. Diagnosis monitor coupler 25. 4WD lamp (For 4WD vehicle only)
6. ABS warning lamp 16. Right-rear wheel speed sensor 26. ECM (PCM) (For 4WD vehicle only)
7. Brake warning lamp (“EBD” warning lamp) 17. Left-rear wheel speed sensor 27. 4WD switch (For 4WD vehicle only)
8. Warning lamp driver module (for ABS) 18. Right-front wheel speed sensor 28. ECM (PCM)
9. ABS hydraulic unit/control module assembly 19. Left-front wheel speed sensor
10. Terminal arrangement of connector E136 for
ABS hydraulic unit/control module assembly20. Data link connector
TERMINAL CIRCUIT TERMINAL CIRCUIT
E1361 Idle up signal
E13614 ABS warning lamp
2 Stop lamp switch 15 Left-front wheel speed sensor (+)
3 Right-front wheel speed sensor (+) 16 Left-front wheel speed sensor (–)
4 Right-front wheel speed sensor (–) 17 4WD switch
5–18 Ignition switch
6 Right-rear wheel speed sensor (–) 19 Left-rear wheel speed sensor (+)
7 Right-rear wheel speed sensor (+) 20 Left-rear wheel speed sensor (–)
8–21 Data link connector
9–22 Ground (for ABS pump motor)
10 Brake warning lamp (EBD warning lamp) 23 ABS pump motor relay
11 G sensor (For 4WD vehicle only) 24 Ground (for ABS control module)
12 Diagnosis switch terminal 25 ABS fail-safe relay
13 Ground (For G sensor) (For 4WD vehicle only)

ANTILOCK BRAKE SYSTEM (ABS) 5E2-19
Table-E EBD Warning Lamp (Brake Warning Lamp) Check – Lamp Comes
“ON” Steady
CIRCUIT DESCRIPTION
EBD warning lamp (brake warning lamp) is controlled by parking brake switch, brake fluid level switch and ABS
control module/hydraulic unit assembly through lamp driver module in combination meter. Refer to “TABLE – A”
for circuit diagram.
INSPECTION
Step Action Yes No
1 1) Make sure that :
Parking brake is completely released.
Brake fluid level is upper than the minimum
level.
Are the check results OK?Go to Step 2. Release parking brake
completely and/or replen-
ish brake fluid.
2Does “ABS” warning lamp come on? Perform “TABLE – B” pre-
viously outlined.Go to Step 3.
3 1) Disconnect ABS hydraulic unit/control mod-
ule connector.
2) Check for proper connection to ABS
hydraulic unit/control module connector at
terminals “E136-10”.
3) If OK, apply chocks to wheels and select
gear in neutral position (P range for A/T).
4) Keep brake pedal depressed and start
engine.
Release parking brake.
5) Connect terminal “E136-10” of discon-
nected connector to ground using service
wire.
Does EBD warning lamp (brake warning lamp)
turn off?Substitute a known-good
ABS hydraulic unit/con-
trol module assembly and
recheck.“BRN” circuit open.
If wire and connection are
OK, replace combination
meter.

5E2-20 ANTILOCK BRAKE SYSTEM (ABS)
DTC C1015 (DTC 15) – G Sensor Circuit and 4WD Lamp Circuit
DESCRIPTION
G sensor
While a vehicle is at stop or running, if the potential difference between the sensor signal terminal “E136-11” and
the sensor ground terminal “E136-13” is not within the specified voltage value, or if the signal voltage while at a
stop does not vary from that while running, this DTC is set.
Therefore, this DTC may be set when a vehicle is lifted up and its wheel(s) is turned. In such case, clear the
DTC and check again.
When G sensor is installed to 2WD vehicle, this DTC is set.
4WD lamp
When 4WD lamp circuit open or shorted, this DTC is set.
1. Ignition switch 3. ABS hydraulic unit/control module assembly 5. 4WD lamp 7. 4WD switch
2. G sensor 4. ABS hydraulic unit/control module connector 6. ECM (PCM)

5E2-22 ANTILOCK BRAKE SYSTEM (ABS)
DTC C1021 (DTC 21), DTC C1022 (DTC 22) – Right-Front Wheel Speed Sensor
Circuit or Sensor Ring
DTC C1025 (DTC 25), DTC C1026 (DTC 26) – Left-Front Wheel Speed Sensor
Circuit or Sensor Ring
DTC C1031 (DTC 31), DTC C1032 (DTC 32) – Right-Rear Wheel Speed Sensor
Circuit or Sensor Ring
DTC C1035 (DTC 35), DTC C1036 (DTC 36) – Left-Rear Wheel Speed Sensor
Circuit or Sensor Ring
DESCRIPTION
The ABS control module monitors the voltage at the terminal of each sensor while the ignition switch is ON.
When the voltage is not within the specified range, an applicable DTC will be set. Also, when no sensor signal is
inputted at starting or while running, an applicable DTC will be set.
1. Ignition switch 4. Right-front wheel speed sensor 7. ABS hydraulic unit/control module connector
2. ABS control module/hydraulic unit assembly 5. Left-rear wheel speed sensor
3. Left-front wheel speed sensor 6. Right-rear wheel speed sensor
NOTE:
When the vehicle was operated in any of the following ways, one of these DTCs may be set even when
the sensor is in good condition. If such possibility is suspected, repair the trouble (dragging of brake,
etc.) of the vehicle, clear DTC once and then after performing the driving test as described in Step 2 of
“ABS DIAGNOSIS FLOW TABLE”, check whether or not any abnormality exists.
The vehicle was driven with parking brake pulled.
The vehicle was driven with brake dragging.
Wheel spin occurred while driving.
Wheel(s) was turned while the vehicle was jacked up.
The vehicle was stuck.

ANTILOCK BRAKE SYSTEM (ABS) 5E2-23
INSPECTION
Step Action Yes No
1 1) Disconnect applicable ABS wheel speed sensor coupler
with ignition switch OFF.
2) Measure resistance between terminals of ABS wheel
speed sensor. Refer to “FRONT WHEEL SPEED SEN-
SOR” and/or “REAR WHEEL SPEED SENSOR” in this
section.
Is measured resistance value as specified?Go to Step 2. Replace ABS wheel
speed sensor
assembly.
2 1) Turn ignition switch OFF.
2) Disconnect ABS hydraulic unit/control module connec-
tor.
3) Check for proper connection to ABS control module at
each sensor terminal.
4) If OK, then turn ignition switch ON and measure voltage
between sensor terminal of module connector and body
ground.
Is it 0V?Go to Step 3. ABS wheel speed
sensor circuit
shorted to power.
3 1) Turn ignition switch OFF.
2) Connect ABS wheel speed sensor coupler.
3) Measure resistance between the following points.
Both ABS hydraulic unit/control module connector termi-
nals of the corresponding sensor.
This check result should be the same as above Step 1.
Either terminal of wheel speed sensor coupler and body
ground.
This check result should be no continuity.
Are both check results OK?Go to Step 4. Circuit open or
shorted to ground.
4 1) Remove applicable ABS wheel speed sensor.
2) Check sensor for damage or foreign material attached.
Is it in good condition?Go to Step 5. Clean, repair or
replace.
5 Check front and/or rear sensor ring for the following
(remove rear drum as necessary) :
Rotor serration (teeth) neither missing nor damaged.
No foreign material being attached.
Rotor not being eccentric.
Wheel bearing free from excessive play.
Are they in good condition?Go to Step 6. Clean, repair or
replace.
6 1) Install ABS wheel speed sensor to knuckle.
2) Tighten sensor bolt to specified torque and check that
there is no clearance between sensor and knuckle.
Is it OK?Go to Step 7. Replace ABS wheel
speed sensor.
7 Referring to “Reference” of “FRONT WHEEL SPEED SEN-
SOR” and/or “Reference” of “REAR WHEEL SPEED SEN-
SOR” in this section, check output voltage or waveform.
Is specified voltage and/or waveform obtained?Substitute a known-
good ABS hydrau-
lic unit/control mod-
ule assembly and
recheck.Replace sensor and
recheck.