1996 ACURA RL KA9 check engine

TCS CONTROL UNIT 20P CONNECTOR

Wire side of female terminals

VB: Battery Voltage

Terminal

number

1

2

4

5

6

9

10

11

12

13

14

15

16

17

20
Wire

color

BLK/YEL

GRN/RED

BLU

PNK/BLU

BLK/WHT

BLK

BRN/WHT

GRN/WHT

BLU

GRN/ORN

BLK/ORN

BRN/BLK

WHT/BLU

BLU/GRY

GRN

BRN
Terminal sign

(Terminal name)

IG1

(Ignition 1)

PARK

(Parking)

SCS

(Service check

signal)

STR-GND

(Steering ground)

AT-SHIFT

(AT shift)

FSR

(Fail-safe relay)

PMG

(Power motor

Ground)

VPM

(Voltage power

motor)

STOP

(Stop)

NEP (Engine

speed pulse)

BARO

(Barometric)

TC-FC

(Traction control

fuel cut)

LG2

(Logic ground 2)

STR-VCC (Steer-

ing power supply)

WARN2

(Warning 2)

SH-MOT

(Shield motor)

MOT +

(Motor +)

MOT-

(Motor -)
Description

Detects ignition switch

IG1 signal

Detects parking brake

switch signal

Detects service check

connector signal

(Diagnostic trouble

code indication)

Ground for the steering

angle sensor

Detects A/T shift posi-

tion signal

Drives fail-safe relay

Power ground for the

TCS control valve

actuator motor

Power source for the

TCS control valve

actuator motor

Detects brake pedal

position switch signal

Detects engine speed

signal

Detects barometric

sensor signal

TCS Fl, Fuel cut

(torque down) signal

Ground for the logic

circuit

Power source for the

steering angle sensor

Drives TCS indicator light

(The indicator light comes

on by the self-bias)

Shield for the TCS con-

trol valve actuator motor

Drives TCS control

valve actuator motor

Drives TCS control

valve actuator motor
Measurement

terminals

1-GND

2

3-GND

4-GND

5-GND

6-GND

9-GND

10-GND

11-GND

12-GND

13-GND

14-GND

15-GND

16-GND

17-GND

19-20

20-19
Voltage

Conditions

(Ignition Switch ON (II))

Depress the parking

brake pedal.

Release the parking

brake pedal.

SCS service connector

connected.

SCS service connector

disconnected.

Shift the transmission

to position, then

start the engine.

Start the engine.

Start the engine.

Brake pedal depressed.

Brake pedal released.

Engine idling

TCS is functioning,

(maximum fuel cut)

TCS is not functioning.

Indicator light ON

Indicator light OFF

TCS is functioning.

TCS is not functioning.

TCS is functioning.

TCS is not functioning.
Output

voltage

VB

Below 0.6 V

VB

0V

5V

Below 0.3V

About 4V

(5V 0V)

VB

1.5V

Below 0.3 V

0V

VB

VB

0V

About 6V

(12V
0V)

About 3 V

About 1.5V

About 4.5 V

(5 V,
PWM)

Below 0.3V

About 5 V

About 2 V

VB

VB

0V

VB

0VProCarManuals.com

Troubleshooting

TC-INH Signal (No PGM-FI DTC is indicated)

Check for a short to body ground

in the TC-INH circuit:

1. Disconnect the PCM connec-

tor C (12P) and TCS control

unit 14P connectors.

2. Check for continuity between

the PCM connector C (12P) ter-

minal No. 9 and body ground.

Is there continuity?

Check the PCM:

1. Connect the PCM connector C

(12P).

2. Start the engine.

3. Measure the voltage between

the PCM connector C (12P) ter-

minal No. 9 and body ground.

Does the tester needle swing

to about 2.5 V?

Check for an open in the TC-INH

circuit:

Measure the voltage between the

TCS control unit 14P connector

terminal No. 8 and body ground.

Does the tester needle swing

to about 2.5 V?

Check for loose TCS control unit

connectors. If necessary, substi-

tute a known-good TCS control

unit and recheck.
PCM CONNECTOR C (12P)

Repair short to body ground in

the wire between the PCM and

TCS control unit.
Wire side of female terminals

NOTE: Check under the following condi-

tions.

The coolant temperature is above 32°F

(0°C).

The MIL does not come on.

NOTE: Use the 10 V range or a similar

range in an analog tester.

Check for loose PCM connectors.

If necessary, substitute a known-

good PCM and recheck.

NOTE: Check under the following condi-

tions.

The coolant temperature is above 32°F

(0°C).

The MIL does not come on.

NOTE: Use the 10 V range or a similar

range in an analog tester.
TCS CONTROL UNIT UP CONNECTOR

Repair open in the wire between

the PCM and TCS control unit.

Wire side of female terminalsProCarManuals.com

PGM-FI DTC : 3 5 (TC-ST B signa l doe s no t matc h TC-F C signal )
Check fo r a shor t t o bod y groun d
i n th e TC-ST B circuit :
1 . Disconnec t th e PC M connec -
to r C (12P ) an d TC S contro l
uni t 14 P connectors .
2 . Chec k fo r continuit y betwee n
th e TC S contro l uni t U P con -
necto r termina l No . 1 0 an d
bod y ground . TC
S CONTRO L UNI T 14 P CONNECTO R
Wir e sid e o f femal e terminal s
I s ther e continuity ? Repai
r shor t t o bod y groun d in
th e wir e betwee n th e PC M an d
TC S contro l unit .
TCS CONTRO L UNI T 20 P CONNECTO R
Chec k fo r a shor t t o bod y groun d
i n th e TC-F C circuit :
1 . Disconnec t th e TC S contro l
uni t 20 P connector .
2 . Chec k fo r continuit y betwee n
termina l No . 1 4 an d bod y
ground .
Is ther e continuity ?Repair shor t t o bod y groun d in
th e wir e betwee n th e PC M an d
TC S contro l unit . Wir
e sid e o f femal e terminal s
Chec k th e TC S contro l uni t (TC -
STB) :1. Connec t th e TC S contro l uni t
14 P an d 20 P connector s an d
PC M connecto r C (12P) .
2 . Rais e th e fron t o f th e vehicle ,
and suppor t i t wit h safet ystands.
3 . Star t th e engine .
4 . Measur e th e voltag e betwee n
th e TC S contro l uni t 14 P con -
necto r termina l No . 1 0 an d
bod y ground . TC
S CONTRO L UNI T U P CONNECTO R
Wir e sid e o f femal e terminal s
I s th e voltag e a s specified ?
TCS is functioning :about 0 V
TC S is no t functioning :
abou t 5 V Chec
k fo r loos e TC S contro l uni t
connectors . I f necessary , substi -
tut e a known-goo d TC S contro l
uni t an d recheck .
To pag e 19-17 4
NOTE : Sto p th e wheel s b y depressin g
th e brak e peda l lightly .
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Troubleshooting
Engine Spee d (NEP ) Signa l
Diagnosti c Troubl e Cod e (DTC ) 3-2 : Engin e Spee d (NEP ) Signa l Diagnosi s
With engin e running , TC S indi -
cato r ligh t i s ON .
Wit h th e SC S servic e connec -
to r connecte d (se e pag e
19-159 ), DT C 3- 2 is indicated .
Chec k fo r a shor t t o bod y groun d
i n th e NE P circuit :
1. Disconnec t th e TC S contro l uni t20P , PC M C (12P ) an d gaug e
assembl y 22 P connectors .
2 . Chec k fo r continuit y betwee n
th e PC M connecto r C (12P ) ter -
mina l No . 8 an d bod y ground .
Is ther e continuity ?
Is ther e abou t 6 V ?
Chec k fo r a n ope n in th e NE P cir -
cuit :
Measur e th e voltag e betwee n th e
TC S contro l uni t 20 P connecto rterminal No . 1 2 an d bod y ground .
Is ther e abou t 6 V ?
Th e syste m is O K a t thi s time .
I f th e proble m recurs , replac e
the TC S contro l unit .
PCM CONNECTO R C (12P )
Wir e sid e o f femal e terminal s
Repai r shor t t o bod y groun d i n
th e wir e betwee n th e TC S contro l
unit , PC M an d gaug e assembly .
Chec k fo r loos e PC M connectors .
I f necessary , substitut e a known -
goo d PC M an d recheck .
NOTE :
Us e th e 1 0 V rang e o r a simila r rang e in a n
analo g tester .
Chec k wit h th e engin e idlin g an d warmed-up .TC
S CONTRO L UNI T 20 P CONNECTO R
Repai r ope n in th e wir e betwee n
th e PC M an d TC S contro l unit .
Wire sid e o f femal e terminal s
Chec
k th e PCM :
1 . Connec t th e PC M connecto r
C(12P).2. Star t th e engine .3. Measur e th e voltag e betwee nthe PC M connecto r C (12P ) ter -mina l No . 8 an d bod y ground .
Use th e 1 0 V rang e o r a simila r rang e in a n
analo g tester .
Check wit h th e engin e idlin g an d warmed-up .
NOTE:
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TCS Contro l Valv e Actuato r
Diagnosti c Troubl e Cod e 5- 4 : Initia l Moto r Operatio n Diagnosi s
5-5 : Moto r Operatio n (1 ) Diagnosi s
5-6 : Moto r Operatio n (2 ) Diagnosi s
5-7 : Ove r Limi t Moto r Curren t Diagnosi s
5-8 : Moto r Drive r Ope n Diagnosi s
5-9 : Unde r Limi t Moto r Curren t Diagnosi s
5-10: Moto r Drive r Shorte d Diagnosi s
With engin e running , TC Sindicato r ligh t i s ON .
Wit h th e SC S servic e connec -
to r connecte d (se e pag e
19-159 ), DT C 5-4 , 5-5 , 5-6 , 5-7 , 5-8 ,5-9 and/o r 5-1 0 ar e indicated .
Chec k th e TC S (1 5 A ) fus e i n th e
under-hoo d fuse/rela y box .
I s th e fus e OK ?
Replace th e fus e an d recheck .
NOTE : Reinstal l th e
fus e i f i t i s OK .
Chec k fo r a n ope n i n th e IG 1 cir -
cuit:1. Tur n th e ignitio n switc h O N (II) .2. Measur e th e voltag e betwee n
th e fail-saf e rela y connecto r ter -
mina l No . 4 an d bod y ground .
NOTE: Star t th e engine , an d rechec k th efuse . I f th e fus e i s blown , chec k fo r ashor t t o bod y groun d in th e VP M circui tbetwee n th e fail-saf e rela y an d TC S con -trol unit .
FAIL-SAF E RELA Y CONNECTO R
Wire sid e o f femal e terminal s
I s ther e batter y voltage ? Repai
r ope n i n th e wir e betwee n
th e EC U (2 0 A ) fus e an d fail-saf e
relay .
Chec k th e fail-saf e rela y (se e
sectio n 23).
I s th e rela y OK ?
Replac e th e fail-saf e relay .TCS CONTRO L UNI T 20 P CONNECTO R
FSR (BLK/WHT )
Check fo r a n ope n in th e FS R cir -cuit :1. Tur n th e ignitio n switc h O N (II) .2. Measur e th e voltag e betwee nthe TC S contro l uni t 20 P con -necto r termina l No . 6 an d bod yground .Wire sid e o f femal e terminal s
I s ther e batter y voltage ?
T o pag e 19-18 8 Repai
r ope n i n th e wir e betwee n
th e fail-saf e rela y an d TC S con -
trol unit .
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Steering Angl e Senso r
Replacemen t
SCREW
CAUTION : D o no t damag e o r dro p th e steerin g angl e senso r a s it i s sensitive .
1 . Remov e th e combinatio n switc h (se e sectio n 17 ).
2 . Remov e th e circli p an d screw , the n remov e th e steerin g angl e senso r fro m th e combinatio n switch .
3 . Installatio n i s i n th e revers e orde r o f removal .
CAUTION : D o no t appl y an y greas e o r oi l t o th e steerin g angl e sensor .
4 . Perfor m th e steerin g angl e senso r syste m check .
STEERIN G ANGL E SENSO R
COMBINATIO N SWITC H
CANCE L CA M
WAV E WASHE R
SPRING
LOWER COVE RJOINT
CIRCLI P
NOTE: Whe n reassembling , alig n th e tab s o f th e join t an dcance l ca m to th e sli t o f th e steerin g angl e sensor .
Steering Angl e Senso r Syste m Chec k
1. Star t th e engine .
2 . Pus h th e TC S switc h 3 time s withi n 3 seconds .
3 . Slowl y tur n th e steerin g whee l clockwis e mor e tha n 1. 5 turns .
NOTE :
Start checkin g afte r th e steerin g whee l move s a t leas t 1. 5 turns .
Tur n th e steerin g whee l slowly , n o faste r tha n 1 tur n in 4 seconds .
4 . Pus h th e TC S switc h twic e withi n 3 seconds .
5 . Slowl y tur n th e steerin g whee l counterclockwise , an d chec k th e numbe r o f time s th e TC S indicato r ligh t flashe s afte r
th e whee l ha s move d abou t 1 turn .
NOTE :
Start countin g afte r th e steerin g whee l move s 1 turn .
Tur n th e steerin g whee l slowly , n o faste r tha n 1 tur n in 4 seconds .
Alway s maintai n th e sam e numbe r o f rotations .
Standar d numbe r o f time s th e TC S indicato r ligh t flashes : 3 time s
6 . I f ther e is a n abnormality , chec k th e troubleshootin g flowchar t (se e pag e 19-168 ).
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Troubleshooting Precaution s
System Indicator s
If th e syste m is OK , th e AB S indicato r goe s of f onc e afte r turnin g th e ignitio n switc h O N (II ) withou t startin g th e engine ,
an d the n com e o n agai n an d g o of f severa l second s late r afte r startin g th e engine . Thi s occur s becaus e th e VS A contro l
uni t i s turne d o n b y th e IG 2 powe r source .
Th e AB S indicato r o r VS A syste m indicato r come s o n whe n th e VS A contro l uni t detect s a proble m in th e system .
Th e AB S indicato r o r VS A syste m indicato r wil l als o com e o n unde r thes e conditions , eve n thoug h th e syste m is oper -
atin g properly :
— Th e vehicl e goe s int o a spi n
— Th e AB S continue s t o operat e fo r a lon g tim e
— Th e vehicl e is subjecte d to a n electrica l signa l disturbanc e
I f ther e is a faul t i n th e PGM-F I system , onl y th e VS A syste m indicato r come s on .
Th e VS A Activatio n Indicato r wil l flas h whe n onl y th e driv e wheel s rotat e o r on e o f th e driv e wheel s is stuck . Whe n thi s
occurs , th e AB S indicato r an d VS A syste m indicato r d o no t com e on .
T o determin e th e actua l caus e o f th e problem , questio n th e custome r abou t th e problem , takin g thes e condition s int o con -
sideration .
Whe n a proble m is detecte d an d th e AB S o r VS A indicato r come s on , ther e ar e case s whe n th e indicato r stay s o n unti l
th e ignitio n switc h i s turne d OFF , an d case s whe n th e indicato r goe s of f automaticall y whe n th e syste m return s t o nor -
mal . Fo r DT C 6 1 an d 62 , th e indicato r goe s of f automaticall y whe n th e syste m return s t o normal . Fo r al l othe r codes ,
th e indicato r stay s o n unti l th e ignitio n switc h is turne d OFF .
Fo r DTC s 12 , 14 , 16 , 18 , 51 , 52 , 53 , 66 , 6 8 an d 84 , th e AB S indicato r goe s of f whe n th e vehicl e is drive n agai n an d th e
syste m is O K afte r th e ignitio n switc h is turne d fro m OF F to O N (II) . However , i f th e DT C is cleared , th e CP U reset s an d
th e indicato r goe s of f righ t afte r th e engin e is starte d if th e syste m is OK .
Th e AB S is no t operationa l whe n th e AB S indicato r i s ON ; th e VS A is no t operationa l whe n th e VS A indicato r i s ON .
Whe n th e VS A indicato r an d MI L ar e bot h ON , troubleshoo t th e PGM-F I syste m first .
Diagnosti c Troubl e Cod e (DTC )
Th e memor y ca n hol d an y numbe r o f DTCs . However , whe n th e sam e DT C is detecte d mor e tha n once , th e mor e recen t
DT C is writte n ove r th e earlie r one . Therefore , whe n th e sam e proble m is detecte d repeatedly , i t i s memorize d a s a sin -
gle DTC .
The DTC s ar e indicate d in ascendin g numbe r order , no t i n th e orde r the y occur .
Th e DTC s ar e memorize d in th e EEPRO M (non-volatil e memory) . Therefore , th e memorize d DTC s canno t b e cancele d
b y disconnectin g th e battery . Perfor m th e specifie d procedure s to clea r th e DTCs .
Self-diagnosi s
Self-diagnosis can be classifie d int o tw o categories :
— Initia l diagnosis : Performe d righ t afte r th e engin e start s an d unti l th e AB S o r VS A indicato r goe s off .
— Regula r diagnosis : Performe d righ t afte r th e initia l diagnosi s unti l th e ignitio n switc h is turne d OFF .
When a proble m is detecte d b y self-diagnosis , th e VS A contro l uni t shift s to fail-saf e mode .
Kickbac k
The pum p moto r operate s whe n th e AB S is functioning , an d th e flui d in th e reservoi r i s force d ou t t o th e maste r cylinder ,
causing kickbac k a t th e brak e pedal .
Pum p Moto r
Th e pum p moto r operate s whe n th e AB S is functioning .
The VS A contro l uni t check s th e pum p moto r operatio n durin g initia l diagnosi s whe n th e vehicl e is started .
You ma y hea r th e moto r operat e a t thi s time , bu t i t i s normal .
Brak e Flui d Replacement/Ai r Bleedin g
Brak e flui d replacemen t an d ai r bleedin g procedure s ar e identica l t o th e procedure s us e o n vehicle s no t equippe d wit h
VSA . T o eas e bleeding , star t wit h th e fron t wheels .
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DTC 11, 13, 15, 17: Wheel Sensor (Open/Short to Body Ground/Short to Power)

Check for a short to power in the

wheel sensor circuit:

1. Disconnect the VSA control

unit 42P connector.

2. Start the engine.

3. Measure the voltage between

the VSA control unit 42P con-

nector appropriate wheel sen-

sor (+) circuit terminal and

body ground (see table).
DTC

11 (Right-front)

13 (Left-front)

15 (Right-rear)

17 (Left-rear)
Appropriate Terminal

(+) Side

No. 16:FRS(+)

No. 28:FLS(+)

No. 31: RRS (+)

No.14: RLS(+)
(-) Side

No. 15: FRS(-)

No. 13:FLS (-)

No. 30:
RRS
(-)

No. 29: RLS (-)
VSA CONTROL UNIT 42P CONNECTOR

Is there battery voltage?
Repair short to power in the {+)

or (-) circuit wire between the

VSA control unit and appropriate

wheel sensor.
Wire side of female terminals

Check for a short to body ground

in the wheel sensor circuit:

1. Turn the ignition switch OFF.

2. Check for continuity between

the VSA control unit 42P con-

nector appropriate wheel sen-

sor (+) circuit terminal and

body ground (see table).

Is there continuity?
Repair short to body ground in

the (+) or (-) circuit wire between

the VSA control unit and the

appropriate wheel sensor.

Replace the appropriate wheel

sensor.

Check for an open in the wheel

sensor circuit:

Measure the resistance between

the VSA control unit 42P connector

appropriate wheel sensor (+) and

(-) circuit terminals (see table).

Is the resistance between

450 - 2,000 at 68°F?
• Repair open in the (+) or (-) cir-

cuit wire between the VSA con-

trol unit and the appropriate

wheel sensor.

• Replace the appropriate wheel

sensor.

Check for loose terminals in the

VSA control unit 42P connector.

If necessary, substitute a known-

good VSA modulator-control

unit, and recheck.ProCarManuals.com