1995 ACURA TL Service Repair Manual

ABS Control Unit Terminal Arrangement

ABS CONTROL UNIT 12P CONNECTOR

Wire side of female terminals

VB: Battery VoltageProCarManuals.com

Troubleshooting Precautions

ABS Indicator Light

1. If the system is OK, the ABS indicator light goes off two seconds after turning the ignition switch ON (II) without start-

ing the engine. After starting the engine, the ABS indicator light comes on again and goes off after two seconds. This

occurs because the ABS control unit is activated by the IG2 power source.

2. The ABS indicator light comes on when the ABS control unit detects a problem in the system. However, even though

the system is normal, the ABS indicator light comes on, too, under the following conditions. To determine the actual

cause of problem, question the customer about the problem, talking the following conditions into consideration.

Only drive wheels rotate

One wheel stuck of drive wheels

Vehicle spin

ABS operate condition continue for long time

Signal disturbance

3. When a problem is detected and the ABS indicator light comes on, there are cases when the indicator light stays on

until the ignition switch is turned OFF, and cases when the indicator light goes off automatically when the system

returns normal. For the DTC 61 and 62, the indicator light goes off automatically when the system returns normal. For

all other codes, the indicator light stays on until the ignition switch is turned OFF.

4. For DTCs 12, 14, 16, 18, 21, 22, 23, 24, 51, 52 and 53, the indicator light goes off when the vehicle is driven again and

the signals are OK after the ignition switch is turned from OFF to ON (II). However, if the DTC is erased, the CPU is

reset and the indicator light goes off right after the engine is started if the signals are OK.

Diagnostic Trouble Code (DTC)

1. The DTC is not memorized if the CPU cannot be activated or the CPU fails and the indicator light comes on.

2. The memory can hold any number of DTCs. However, when the same DTC is detected more than once, the later one

is written over the old one. Therefore, when the same problem is detected repeatedly, it is memorized as one DTC.

3. The DTCs are indicated in the order of ascending number, not in the order they occur.

4. The DTCs are memorized in the EEPROM (non-volatile memory). Therefore, the memorized DTCs cannot be canceled

by disconnecting the battery. Perform the specified procedures to erase the DTCs.

Self-diagnosis

1. The self-diagnosis can be classified into two categories.

Initial diagnosis: Performed right after the engine starts and until the ABS indicator light goes off.

Regular diagnosis: Performed right after the initial diagnosis until the ignition switch is turned OFF.

2. When a problem is detected by self-diagnosis, the system

Turns the ABS indicator light ON

Memorizes the DTC

Turns the fail-safe relay OFF

Stops ABS controlProCarManuals.com

Troubleshooting Precautions

Kickback

1. The motor operates when the ABS is functioning, and the fluid in the reservoir is forced out to the master cylinder

causing kickback at the brake pedal.

Pump Motor

1. The pump motor operates when the ABS is functioning.

2. The ABS control unit checks the pump motor operation during initial diagnosis and vehicle starts. You may hear the

faint operation sound at this time, but it is normal.

Brake Fluid Replacement/Air Bleeding

1. Brake fluid replacement and air bleeding procedures are the same as vehicles without ABS. To ease bleeding, start

with the front wheels.

Troubleshooting

1. The troubleshooting flowcharts procedures assume that the cause of the problem is still present and the ABS indica-

tor light is still on. Following the flowchart when the ABS indicator light does not come on can result in incorrect

judgment.

2. Question the customer about the conditions when the problem occurred, and try to reproduce the same conditions

for troubleshooting.

Find out when the ABS indicator light came on, such as during initial diagnosis, during ABS control, after ABS con-

trol, when the vehicle started, when vehicle speed was at 19 mph (30 km/h), when the problem continued for a few

seconds or a few minutes, etc.

3. When the ABS indicator light does not come on during the test-drive, but the troubleshooting is performed based on

the DTC, check for the loose connectors, poor contact of the terminals, etc, before troubleshooting.

4. After troubleshooting, erase the DTC and test-drive the vehicle. Be sure that the ABS indicator light does not come on.

5. The connector illustrations show the female connectors with a single outline and the male connectors with a double

outline.ProCarManuals.com

Diagnostic Troubl e Cod e (DTC )
Diagnosti c Troubl e Cod e (DTC ) Indicatio n (SC S Mode )
NOTE: Thi s operatio n ca n als o b e don e wit h th e Hond a PG M Tester .
1 . Connec t th e SC S servic e connecto r t o th e servic e chec k connecto r (2P ) unde r th e glov e box .
2 . Tur n th e ignitio n switc h O N (II ) withou t brak e peda l depressed .
NOTE : I f th e brak e peda l i s depresse d whe n turnin g th e ignitio n switc h O N (II) , th e syste m shift s t o ME S mode .
3 . Th e blinkin g frequenc y indicate s th e DTC .
NOTE : I f th e DT C is no t memorized , th e AB S indicato r ligh t goe s of f fo r 3. 6 second s an d the n stay s on .
4 . Tur n th e ignitio n switc h OFF , an d remov e th e SC S servic e connector .
NOTE : Th e Malfunctio n Indicato r Lam p (MIL ) wil l sta y o n afte r th e engin e i s starte d i f th e SC S servic e connecto r i s
connected .
Condition s fo r DT C indicatio n
Vehicl e spee d is a t 6 mp h (1 0 km/h ) o r less .
Th e SC S servic e connecto r i s connecte d befor e th e ignitio n switc h i s turne d O N (II) .
Th e brak e peda l i s released .
SCS SERVIC E CONNECTO R07PAZ - 001010 0
SERVIC E CHEC KCONNECTO R (2P )
ABS INDICATO R LIGH T
When ignitio n switc h i s turne d O N (II) , th e AB S indicato r ligh t come s o n fo r tw o second s t o chec k th e bulb . D o no t
coun t thi s a s a DTC .
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Diagnostic Trouble Code (DTC)

DTC Erasure (MES Mode)

NOTE: This operation can also be done with the Honda PGM Tester.

1. Connect the SCS service connector to the service check connector (2P) under the glove box.

2. Depress the brake pedal.

3. Turn the ignition switch ON (II) while keeping the brake pedal depressed.

4. After the ABS indicator light goes off, release the brake pedal.

5. After the indicator light comes on, depress the brake pedal again.

6. After the indicator light goes off, release the brake pedal again.

7. After few seconds, the indicator light blinks twice and the DTC is erased. If the indicator light does not blink twice,

repeat steps 1 through 6. If the indicator light stays ON after the indicator light blinks twice, check the DTC because a

problem was detected during initial diagnosis before shifting to MES mode.

8. Turn the ignition switch OFF, and remove the SCS service connector.

Conditions for DTC erasure

Vehicle speed is at 6 mph (10 km/h) or less.

The SCS service connector is connected before the ignition switch is turned ON (II).

The brake pedal is depressed before the ignition switch is turned ON (II).ProCarManuals.com

Troubleshooting Inde x
NOTE : Thi s operatio n ca n als o b e don e wit h th e Hond a PG M Tester .
REFERTOPAG E
19-14 2
19-14 4
19-145
19-146
19-147
19-148
19-151
19-152
19-153
19-156
19-158
19-160
19-161
19-161
*1: Whe n th e proble m is detecte d an d AB S Indicato r ligh t come s on , th e indicato r ligh t wil l sta y o n unti l th e ignitio n switc h is
turne d fro m OF F to O N (II) , an d th e contro l uni t confirm s tha t th e syste m is O K whe n th e vehicl e starts .
*2 : Whe n voltag e return s normal , th e AB S indicato r ligh t goe s off .
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Modulator Unit

Removal/Installation

CAUTION:

Do not spill brake fluid on the vehicle; it may damage the paint; if brake fluid does contact the paint, wash it off

immediately with water.

Take care not to damage or deform the brake lines during removal and installation.

To prevent the brake fluid from flowing, plug and cover the hose ends and joints with a shop towel or equivalent

material.

NOTE: Tighten the flare nuts to 15 N-m (1.5 kgf-m, 11 Ibf-ft).

Removal

1. Disconnect the modulator unit 10P and pump motor 2P connectors.

2. Remove the proportioning control valve.

3. Disconnect the brake lines, then remove the modulator unit.

Installation

1. Install the modulator unit, then connect the brake lines.

2. Install the proportioning control valve.

3. Connect the modulator unit 10P and pump motor 2P connectors.

4. Bleed the brake system, starting with the front wheels.

5. Start the engine, and check that the ABS indicator light goes off.

6. Test-drive the vehicle, and check that the ABS indicator light does not come on.

MODULATOR UNIT

10P CONNECTOR
From right-front

From left-front

PUMP MOTOR

2P CONNECTOR

6 mm BOLT

9.8 N-m (1 .0 kgf-m, 7 Ibf-ft) PROPORTIONING

CONTROL

VALVE

6 mm NUT

9.8 N-m (1.0 kgf-m, 7 Ibf-ft)

BRACKET
RUBBER MOUNT

MODULATOR UNIT

8 mm BOLT

22 N-m (2.2 kgf-m, 16 Ibf-ft)ProCarManuals.com

ABS Contro l Uni t
Pulsers/Whee l
Sensors
Replacemen t
1. Remov e th e glov e bo x (se e sectio n 20 ).
2 . Remov e th e fou r mountin g bolt s o f th e AB S contro l
uni t moun t bracket .
'97 AB S CONTRO L UNI TRADIATO R FA N CONTRO L '9 8 AB S CONTRO L UNI T isMODUL E CONNECTO R behin d th e moun t bracke t
3.
4 .
5.
6.
AB S CONTRO L UNI TCONNECTOR S
ABS CONTRO L UNI TMOUN T BRACKE T
Move th e bracke t forward , an d disconnec t th e eac h
connector s fro m th e bracket .
Disconnec t th e AB S contro l uni t connector s an d
radiato r fa n contro l modul e connector .
Mov e th e bracke t dow n to remov e it fro m th e car .
Remov e th e radiato r fa n contro l modul e an d thre e
AB S contro l uni t mountin g bolts .
'97 AB S CONTRO L UNI T
ABS CONTRO L UNI TMOUN T BRACKE T
RADIATO R FA N
CONTRO L MODUL E
ABS CONTRO L UNI TMOUNTIN G BOLT S9.8 N- m (1. 0 kgf-m , 7 Ibf-ft )
7. Remov e th e AB S contro l uni t fro m th e bracket .
8 . Instal l th e AB S contro l uni t i n th e revers e orde r o f
removal .
Inspectio n
1. Chec k th e fron t an d rea r pulse r fo r chippe d o r dam -
age d teeth .
2 . Measur e th e ai r ga p betwee n th e whee l senso r an d
pulse r al l th e wa y aroun d whil e rotatin g th e pulser .
Standard : 0. 4 - 1. 0 m m (0.0 2 - 0.0 4 in )
NOTE : I f th e ga p exceed s 1. 0 m m (0.0 4 in) , th e
probabilit y i s a distorte d suspensio n ar m whic h
shoul d b e replaced .
Front/Rea r
0.4- 1.0 m m(0.0 2 - 0.04 in)
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