1999 HONDA CIVIC Transmission

Brake Booster InsPection
FunctionalTest
1. With the engine stopped, depress the brake pedal
several times to deplete the vacuum reservoir, then
depress the pedal hard and hold it for 15 seconds lf
the pedal sinks' either the master cYlinder is
bypassing internally, or the brake system (master
cylinder. lines. modulator, proportioning control
valve, or caliPer) is ieaking.
2. Start the engine with the pedal depressed lf the
pedal sinks slightly, the vacuum booster is operating
normally. lf the pedal height does not vary, the
booster or check valve is faultY.
3. With the engine running. depress the brake pedal
lightly. Apply just enough pressure to hold back
automatic transmission creep. lf the brake pedal
sinks more than 25 mm (1.0 in.) in three minutes,
the master cvlinder is faulty. A slight change in
pedal height when the A'lC compressor cycles on
and off if normal. (The A/C compressor load
changes the vacuum available to the booster')
Leak Test
1. Depress the brake pedal with the engine running.
then stop the engine. lf the pedal height does not
vary while depressed for 30 seconds, the vacuum
booster is OK. lf the pedal rises. the booster is
faulty.
2, With the engine stopped, depress the brake pedal
several times using normal pressure When the
Dedal is first depressed, it should be low On con-
secutive applications, the pedal height should grad-
uallv rise. lf the pedal position does not vary, checK
the booster check valve.
l./
19-23
Booster Check Valve Test
1. Disconnect the brake booster vacuum hose at the
booster.
2. Stan the engine and let it idle. There should be vac-
uum. lf no vacuum is available, the check valve is
not working properly. Replace the brake booster
vacuum hose and check valve, and retest.
BRAKE BOOSTERVACUUM HOSE(Check valve
built-in)

l'f .
Electrical
Special Toofs .,....................,23-2
Troubleshooting
Tips and Precautions ..............,.................... . 23-3
Five-step Troubleshooting .............. ......... . . 23-5
wire color codes ..........,23-5
Schematic Symbols ........,................... . . .. .... 23-6
Relay and Control Unit Locations
Engine Compartment ...,..................... ... .. . 23'7
Dashboard ......................23-8
Dashboard/Door ......... 23-12*Airbags ................. ....... Section 24
Air Conditioning ......... Section 21
Aftelnator ..........."""" """ 23-112
Anti-lock Brake System {ABS) Section 19*A/T Gear Position Indicator .....................,. .... ... 23-149
Automatic Transmission Svstem .... . ....... Section 14
Batterv ......... . . . ... ...... .......23-91
Blower controls .. . ... Section 2l
Charging System ....'...........23'112
Connector ldentilication and Wire Harness
Routing .................. ......23'13
Cruise Control ............,........23-240
Dash Lights Brightness Controller ............. ....... 23-180
Fan controfs "" 23'126
Fuel PumD ........ . ........ section 11
Fuses/Refay ...............,..,,.. 23'62
PGM-FI Control System ......................,....... Section 1 1
*Gauges
Circuit Diagram ....,.,.......23-131
Fuef Gauge ...........'.'.......23-142
Gauge/lndicator .. . .. 23-129
Ground Distribution .. . 23-75
Heatei controls .. . ..... Section 21*Horn................. ...............23-196
*tgnition Switch ....................23-89
lgnition System .......,.... 23-102
*lntegrated Control Unit ....................................... 23-156
fnterlock System ,........ . . , ,23-144
Lighting System . . . .. ......... 23-161
Lights, Exterior
Back-up Lights ..'............23'171
Brake Lights .................. 23'174
Daytime Bunning Lights (Canadal ............... 23'166
Front Parking Lights ......,................ .'. .......... 23-167
Front Turn Signal Lights .......... . . ............ ..,.23-167
Headtights ....".'....-... ..... 23'167
High Mount Brake Light ...................... ... .23'179
License Plate Lights ...... 23'176
Taitfights ................ .......23'171
lnterior Lights ..-.......,, . 23-142
Moonroof ..,.................,........ 23-235
Power Distribution ....... . . .23-61
Power Door Locks .......,,,. .23'251
Power Mirrors ,..............,.,...23'206
Power Relays ....... . ...... . . .. 23-86
Power Windows ............,,....23-220
Rear Window Defogger .......................... . . ... . . 23-2OO
Spark Plugs . ..... . ........ .....23-111
Slarting System ................23-93*stereo Sound Svstem ,................. ..... ... . ... ,.,.,,23'147'Supplemental Restraint System (SRS) ... . Section 24
Turn Signal/Hazard Flasher System .......'.'....-... 23-173
*Undel-dash Fuse/Relay Box ............,.................. 23-85
vehicfe soeed sensor (VSSI """" ""' 23-140+Wipers/Washers .........,.,.,...23-214
NOTE: Unless otherwise specified, references to auto-
matic transmission (Mf) in this section include the CVT.

Connector ldentification and Wire Harness Routing
Connector or
Terminal
Number of
CavitiesLocalionConnec{s toNotes
T,I
r2
Right side of engine compartment
Right side of engine compartment
Under-hood fuse/relay box
Starter motor
BatteryBattery positive terminal
Starter Cables
A/C Wire Harness
Battery Ground Cable
Connector or
Terminal
Number of
CavitiesLocationConn€cts toNotos
Right front shock towerBody ground, via battery ground
caDte
oBafteryBattery negative terminal
Engine Ground Cable A
Conn€qtor or
Terminal
Number ot
CavitiosLocationConnects toNoles
T3Left side of enginePower steering pump bracket
G2Left side of engine compartmentBody ground, via engine ground
cable A
Engine Ground Cable B
Connector or
Terminal
Number of
CavitiesLocationConnecls toNoles
T4Right side of engine compartmentTransmission
Right side of front frameBody ground, via engine ground
cable B
Under-hood ABS Fusa/Relay Box Wire Harness
Connector or
Tgrminal
Number oI
CavitiesLocationConneqts toNotes
T5Right side of engine compartmentUnder-hood fuse/relay box
@BaneryBattery positive terminal
Connector or
Terminal
Number of
CavitiesLocationConnects toNotes
c753
c754
1
2
Right side of engine compartment
Right side of engine compartment
Right side of engine compartment
Right side of engine compartment
Engine compartment wire harness(c209)
Compressor clutch
Condenser fan motor
A,/C pressure switch
Left side of engine compartmentBody ground, via A,/C wire harness
23-14

Connector ldentification and Wire Harness Routing
Connector or
Terminal
Number of
CavhiosLocationConnocts ioNotes
c401
c402
c403
c404
c405
c406
c407
c407
c408
c409
c410
c411
c412
c413
c414
c415
c416
c417
c418
c4l9
c420
c42'l
c423
c424
c425
c426
c427
c42A
c429
c430
c431
c432
c433
c434
c435
c431
c438
c439
'14
't4
I
I
10't2
24
16
7
o
18
20
18
7
6
I
o
4
7
8
14
1
Above under-dash fuss/relay box
Under left side ot dash
Under left sid€ of dash
Under left side of dash
Under left side of dash
Und€r left side of dash
Under left side of dash
Under left side of dash
Under left side of dash
Behind under-dash fuse/relay box
Under left side of dash
Under left side of dash
Above under-dash fuse/relay box
Under left side of dash
Under left side of dash
Above under-dash fuse/r€lay box
Under left side of dash
Under left side of dash
Under left side of dash
Behind under-dash fuse/relay box
Eehind under-dash fuse/relay box
Behind under-dash fuse/relay box
Behind under-dash fuse/relay box
Behind under-dash fuse/relay box
Under left side of dash
Under left side of dash
In the steering column cover
In the steering column cover
In the steering column cover
In the steering column covEr
Under left side of dash
Under left side of dash
Under middle of dash
Under middle of dash
Under middle of dash
Under middle of dash
Under left side of dash
Under left side of dash
Eehind under-dash fus€/relay box
Floo. wire harness (C555)
Floor wire harness (C554)
Security system
Cruise control unit
Daytime running lights control unit
Daytime running lights control unit
Roof wire harness (C701)
Moonroof wire harness (C7l1)
Front fog light connector
Integrated control unit
Dashboard wire harness (C504)
Dashboard wire harness (C502)
SRS main harness (C802)
Data link connector
Starter cut relay
lgnition switch
Security system
Clutch switch
Clutch interlock switch
Under-dash fuss/relay box (C9191
Undor-dash fuse/r€lay box {C920)
Under-dash tuse/relay box (C922)
Under-dash luse/relay box (C914)
Under-dash fuse/rBlay box (C915)
Horn relay
Brake swilch
Windshield wiper/washer switch
Rear window wiper/washer switch
Turn signal switch
Combination lighvturn signal switch
Cable reel
lnterlock control unit
Secondary heated oxygen sensor sub-
harn€ss (C781)
Ay'T gear position switch
Shift lock solenoid
Park pin switch and Ay'T gear position
console light
Transmission control module (TCM)
Transmission control module {TCM)
Under-dash fuse/relay box {C925)
ABS
Optional
Canada
Canada
Optional
Atr
MTT
Optional
Mlf
NT
Atf
CVT
CVT
Optional
AN
Atr
G401Left kick panelBody ground, via main wire harness
Main Wir€ Harness (Loft side of da3h and floor branch): '96 - 97 models
*2:Without moonroof*4: With moonroof*5: M/T (with cruise control or for D16Y5 engine)*6: With secondary heated oxygen sensor (H02S)
23-32

Connector ldentification and Wire Harness Routing
Connoctor or
Tgrminal
Number of
CavitiesLocationConneqts toNot€s
c401
c402
c403
c404
c405
c406
c407
c407
c408
c409
c410
c411
c4't2
c413
c414
c415
c416
c417
c418
c419
c420
c421
c422
c423
c424
c425
c426
c427
c428
c429
c430
c431
c432
c433
c434
c435
c437
c438
't4
l4
8,
1
10
12
24
7
6
18
20
18
7
6
8
7
8
14
2
Above under-dash fuse/relay box
Under left side of dash
Under left side of dash
Under left side of dash
Under left side of dash
Under left side of dash
Under left side of dash
Under left side of dash
Under left side of dash
Behind under-dash fuss/relay box
Under left side of dash
Under left side of dash
Above under-dash fuse/relay box
Under left side of dash
Under-dash relay box
Above under-dash fuse/relay box
Under left side of dash
Under left side of dash
Under left side of dash
Eehind under-dash fuse/relay box
Behind under-dash fuse/relay box
Behind under-dash fuse/relay box
Behind under-dash fuse/rslay box
Behind under-dash fuse/relay box
Under-dash relay box
Under left side of dash
In the steering column cover
In the steering column cover
In the steering column cover
In the steering column cover
Under left side of dash
Under left side of dash
Under middle of dash
Under middle of dash
Under middle of dash
Under middle of dash
Under left side of dash
Under left side of dash
Floor wire harness (C555)
Floor wire harness (C554)
Security system
Cruise control unit
Daytime running lights control unit
Daytime running lights control unit
Roof wiro harness (C7011
Moonroof wire harness (C711)
Front fog light connector
Integrated control unit
Dashboard wire harness (C504)
Dashboard wire harness (C502)
SRS main harness (C802)
Data link connector
Starter cut relay
lgnition switch
Security system
Clutch switch
Clutch inlerlock switch
Under-dash fuse/relay box (C919)
Under-dash fuse/relay box (C920)
Under-dash fuse/relay box (C922)
Under-dash fuse/relay box (C914)
Under-dash fuse/relay box (C915)
Horn relay
Brake switch
Windshield wiper/washer switch
Rear window wiper/washer switch
Turn signal switch
Combination light/,turn signal switch
Cable reel
lnterlock control unit
Secondary heated orygen sensor sub-
harness (C781)
Ay'T gear position switch
Shift lock solenoid
Park pin switch and Aff gear position
console light
Transmission control module (TCMI
Transmission control module (TCM)
ABS
Optional
Canada
Canada
Optional
M
MIT
Optionsl
MlT
Alr
NT
NT
CVT
CVT
G401Left kick panelBody ground, via main wire harness
Main Wire Harn€ss {Left side ot dash and floor branchl: '98 model
*2: Without moonroof*4:With moonroof*5: M/T (with cruise control or for D16Y5 engine)*6: With secondary heated oxygen sensor (H02S)
23-34

Contents
How to Use This Manual ICircuit Schematics (see Circuit Index)Fuse/Relaylnformation 6Ground-to-Componentslndex 6-6ComponentLocationPhotooraohs 201Conriector Views 202
Circuit Index
Accessory power socket 155Air conditionerAir delivery'96198 models 61'99-'00 models 61-2Blower controls'96198 models 60'99100 models 60-1Compressor controls 62Fans 63Anti-lock brake system (ABS) 44A/T gear position indicatorCVT 89All except CVT 89-1Automatic transmission controlsAll '96-'98 models except CVT and GX 39All '99100 models except CVT 39-8All GX models 39-8'96-'98 CVT 39-4'99100 cw 39-12Back-up lightsCoupe and Sedan 110Hatchback l'10-1Brake lightsAll Coupes and'96-'98 Sedans 110-15'99-'00 Sedans 110-16Hatchback 110-17Brake system indicator light'96198 models 7'1'99100 models 71-1Ceiling light 114-3Charging system 22Condenser fan 63Console lights 114Cruise control 34Dash lights 114Daytime running lights 110- 13Engine coolant temperature gauge 81-1Fog lights 110-10Front parking lights 110-2Fuel gauge 81-1Fuse/relay boxUnder-dash 6Under-hood 6-4Underhood ABS 6-3Gauges 81Ground distribution 14Ground-to-Componentslndex 6-6Hazard warning lightsAll except '99100 Sedans 110-6'99100 Sedans 110-8Headlights 110-12Headlight switch 100Heater - See Air ConditionerHorn'96197 models 40'98 model 40-1'99100 models 40-2lgnition key reminder 73lgnition systemAll '96198 models except Dl685 20All '99100 models except D16Y5 with Mn 2O-2All D1685 engines 20-2'99-'00 D 16Y5 with M/T 20
lndicators 80Integrated control unit 70lnterlock systemAll except'96J98 CVT 138'96198CVT 138-1License plate lightsAll Coupes and '96-'98 Sedans I l0-3'99100 Sedans 1 10-4Hatchback 110-5Low fuel indicator light 74Moonrool'96197 models |22'98-'00 models 122-1Odometer 81Oil pressure indicator light 80-3Power distributionBattery to ignition switch, fuses, and relaysFuses to relays and components 10-2Power door locksAll models without keyless entry 130'96-'98 models with keyless entry 130-2'99100 models with keyless entry 130-12Power mirrorsWithout detogger 141With defogger '141-2
Power windows 120Programmed fuel injection system (PGNr-Fl)All '96-98 models except D1685 23All '99-'00 models except D16Y5with M/T and D1685 24All D1685 engines 25'99100 D16Y5 with M/T 23Radiator fan 63Rear window defogger'96-,98 models 64'99100 models 64-1Seat belt reminder 73Security system'96.'98 USA HX, LX, EX 133'96-'98 Canada EX, Si 133'99TOO USA HX, LX, EX, DX.V Si 133-4'99100 Canada EX, Si 133-4All CX and DX models 133-8Speedometer 81Starting systemA./T (All except Dl685) 21A"/r (D16Bs) 21-1Manualtransmission 21-2Slereo sound system 150Supplemental rastraint system (SRS) 47Tachometer 81TailliqhtsAllboupes and'96-'98 Sedans 110-3'99100 Sedans 1 10-4Hatchback 110-5Trunk light 114-3Turn signal lightsAll except'99100 Sedans 110-6'99-'00 Sedans 1 10-8Vehicle speed sensor (VSS) 33Wiper/washerFront 91Rear 92
10

Ground-to-Components I ndex
f.,lONOTE: All ground wires are BLK unless otherwise noted.
GroundPageComponents or Circuit Grounded
Battery (BLKYEL)
Steering pump bracket
t+-rg ITransmission housing
l
G101
(-1)
G101
(-2)
14-2
and
14-3
ano
14-1
Powertrain or engine control module (PG1 and pG2 are BLK: LG1 and LG2 are
BRN/BLK), EGR control solenoid valve (CW, EGR valve and lift sensor (Dt6yS enginewith M,/T), Engine coolant temperature switch, pGM-Fl main relay, power steeringpressure switch (USA), Primary HO2S (D16Y5 engine with l\/,/T), Vehicle speed sensor,VTEC pressure switch (D16Y5/D16Y8 engines), CKF sensor (BRN/BLK), Transmission
control module (CYf) (Pc1 is BLK: LG1 is BRN/BLK)
Shielding betvveen the PCM or ECM and these components (all have BRN/BLK wires):
CKF sensor, TDC/CKP/CYP sensor. Primary and secondary heated oxygen sensors.
Knock sensor (CWDl6YB engine), Mainshaft speed sensor (AiT except CVT),
I Countershaft speed sensor (A/T except CVf)
Shielding between the TCM and these components (CVT) (all have BRN/BLK wires):
Drive pulley speed sensor, Driven pulley speed sensor, Secondary gear shaft
speed sensor
Powertrain or engine control module (PG1 and pG2 are BLK; LG1 and LGz are
BRN/BLK), EGR control solenoid valve (D16Y5 engine), EGR valve (Dt685), Engine
coolant temperature switch, Fuel pressure regulator shut-off solenoid valve (D1685),
PGM-FI main relay, Power steering pressure switch (USA), Vehicle speed sensor, VTECpressure switch (All except D16Y7 engine), CKF sensor (A

except 81642) (BRN/BLK)
Shielding between the PCM or ECM and these components (all have BRN/BLK wires):
CKF sensor, TDC/CKP/CYP sensor, Primary and secondary heated oxygen sensors,
Knock sensor (All except D16Y7 engine), i/ainshaft speed sensor (Arf except CW),
Countershaft speed sensor (A,/T except CVf), Drive pulley speed sensor (CW), Drivenpulley speed sensor (CVT), Secondary gear shaft speed sensor (CVf)
I Badiator fan motor, Right front parking/turn signat tight, Right headtight
G20214-4I Cruise control actuator, Left front parking/turn signal lights, Left headlight, Rear window
I washer motor, Windshield washer motor, Washer fluid level switch (,99-'00 Canada)
G401| +-o
and
14-7
Accessory power socket, Brake fluid level switch, Clutch interlock switch (M/T), Clutchswitch (lillT with cruise/D16Y5 engine with MfD, Combination wiper switch (Z wires),
Cruise control main switch, Cruise control unit, Dash lights brightness controller, Data
link connector, Daytime running lights control unit (Canada), Gauge assembly, Horn('96-'97 models), Integrated control unit, Interlock control unit (ArI), Keyless door lock
control unit ('99-'00 models with keyless), Moonroof close and open relays, Moonroof
switch, Park pin switch (A/r), Power window relay, Rear window defogger relay, Rear
window defogger switch ('96-'98 models), Steering lock, Stereo radio tuner (,96-,98
USA: LX, EX, and HX), Turn signal/hazard relay, Windshield wiper motor.....plus
everything grounded through G402
6-6

Power Distribution
- From Fuses to Relays and Components (contd)
FUSE 15AIITIFIIATORsP iE soa754
J-l
c4t912 I C421PHO|O 63virtu is-- : : I lj;:o,19^63
l,lll,nl
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: i Page 22
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VEW 5A
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TRANSMISSIONCONTROLMODULE [rCM]Page 39-4
vtEw 69
815
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GAUGEASSEMBLYPage 22-1
, a PHO|O S
, UNDER-HOOD' FUSE/RELAY BOXI PHO|O 7
- '96-'98 CVT
10-4