Due to the adoption of the electronic brake-force
distribution (EBD*) system to secure the maximum
braking force regardless of laden conditions of a
vehicle, the layout of the ABS-ECU terminals and
ABS circuit have been changed so that the service
procedures have been established.

NOTE
*EBD: Electronic Brake-force Distribtion

EBD CONTROL

The vehicle with ABS can electronically control brake
fluid pressure to rear brakes during applying braking
force corresponding to deceleration and slip at the
front/rear wheels calculated by wheel speed sensor
signals using rear wheel solenoid valves. EBD

control allows braking force of the vehicle to be
compatible with stability at a high level characterized
by the following features:

Since ideal braking force to rear wheels can be
obtained regardless of laden conditions of the
vehicle or road surface, applied force to the
braking pedal on a high-friction coefficient road
can be reduced especially when the vehicle is
laden.

Due to a reduction of the load on the front brakes,
temperature increase in the pads during
applying braking force can be suppressed.
Thus, tolerance for wear is improved.

Control valves, such as proportioning valves
are unnecessary.

TROUBLESHOOTING

The same procedures as before are applied except for the items shown below.

INSPECTION CHART FOR DIAGNOSIS CODES

Diagnosis
code No.

Inspection item

Diagnosis content

Reference page

Front right wheel speed sensor

Open circuit

35B-3

Front left wheel speed sensor

Rear right wheel speed sensor

Rear left wheel speed sensor

Front right wheel speed sensor

Short circuit

35B-3

Front left wheel speed sensor

Rear right wheel speed sensor

Rear left wheel speed sensor

Stop lamp switch system

35B-4

ABS <2WD> –

Troubleshooting

35B-3

INSPECTION PROCEDURE FOR DIAGNOSIS CODES

Code Nos.11, 12, 13 and 14 Wheel speed sensor open
circuit

Probable cause

Code Nos.21, 22, 23 and 24 Wheel speed sensor short
circuit

Code Nos.11, 12, 13 and 14 are output if the ABS-ECU detects an open circuit
in any one of the four wheel speed sensors.

Malfunction of wheel speed sensor

Malfunction of wiring harness or connector

Malfunction of ABS-ECU

Code Nos.21, 22, 23 and 24 are output in the following cases.

When there is no input from any one of the four wheel speed sensors when
traveling at 12 km/h or more, even though open circuit verified.

When a chipped or blocked-up ABS rotor is detected during driving at 12 km/h
or more.

Malfunction of wheel speed sensor

Malfunction of wiring harness or connector

Malfunction of rotor

Malfunction of ABS-ECU

Malfunction of wheel bearing

Wheel speed sensor installation in-
spection.

Repair

Measure at the ABS-ECU connector
A-47.

Disconnect the connector and
measure from the harness side.

Resistance values between 1 and
2, 4 and 5, 6 and 7, 8 and 9.
OK: 1.28 – 1.92 k

Ω

Check the following connectors:
A-22, A-02, B-42, D-15, D-14, D-12

Repair

Check trouble symptoms.

Check the harness wire between each
wheel speed sensor and ABS-ECU,
and repair if necessary.

Wheel speed sensor output voltage in-
spection

Wheel speed sensor inspection

Replace the wheel speed sensor.

Rotor inspection

Replace the rotor.

Wheel bearing inspection

Check the following connector:
A-47

Repair

Check trouble symptoms.

Replace the hydraulic unit assembly.

ABS <2WD> –

Troubleshooting

35B-4

Code No. 38 Stop lamp switch system

Probable cause

These codes are output at the following times:

When the stop lamp switch is not be turned off (when the stop lamp switch
stays on for 15 minutes or more although the ABS is not operating).

When the ABS-ECU determines that there is an open circuit in harness of the
stop lamp switch system.

Malfunction of stop lamp switch

Malfunction of harness or connector

Malfunction of ABS-ECU

Does the stop lamp illuminate and
switch off normally?

Stop lamp switch installation inspection.

Repair

Stop lamp switch inspection.

Replace the stop lamp switch.

Check the harness between dedicated
fuse No. 8 and the ABS-ECU, and re-
pair if necessary.

Yes

Measure at ABS-ECU connector A-47.

Disconnect the connector and
measure at the harness side.

Stop lamp switch ON.

Voltage between 14 – body earth
OK: System voltage

Check the following connectors:
A-47, B-42, B-61X, B-39<Petrol engine
vehicles>, B-95<Diesel engine
vehicles>, B-43

Repair

Check trouble symptom.

Check the harness between dedicated
fuse No. 8 and the ABS-ECU, and repair
if necessary.

Check the following connector:
A-47

Repair

Check trouble symptom.

Replace the hydraulic unit assembly.

INSPECTION CHART FOR TROUBLE SYMPTOMS

Get an understanding of the trouble symptoms and check according to the inspection procedure chart.

Trouble symptoms

Inspection
procedure
No.

Reference
page

Communication with MUT-

Communication with ABS only is not possible.

35B-5

Communication with MUT

is not possible.

Communication with ABS only is not ossible.

35B 5

Faulty ABS operation

Unequal braking power on both sides.

35B-6

Insufficient braking power.

ABS operates under normal braking conditions.

ABS operates before vehicle stops under normal
braking conditions.

Large brake pedal vibration (Caution 2).

–

Caution
1.

If steering movements are made when driving at high speed, or when driving on road surfaces
with low frictional resistance, or when passing over bumps, the ABS may operate even though
sudden braking is not being applied. Because of this, when getting information from the customer,
check if the problem occurred while driving under such conditions as these.

During ABS operation, the brake pedal may vibrate or may not be able to be depressed. Such
phenomena are due to intermittent changes in hydraulic pressure inside the brake line to prevent
the wheels from locking and is not an abnormality.

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