1999 HONDA CIVIC Brake light switch

)
CavityWireTest conditionTest: Desired resultPossible cause if result is not obtained
BRNA/VHTUnder all conditionsCheck for resistance to ground:
There should be 80 - 120 O.
Fau lty actuator solenoid
Poor ground (G202)
An open in the wire
1BRNUnder all conditionsCheck for resistance to ground:
There should be 40 - 60 0.
11BRN/BLKUnder all conditionsCheck for resistance to ground:
There should be 70 - 110 0.
2GRY
lgn jtion switch ON (ll),
main switch ON and
brake pedal pushed,
then released
Check for voltage to ground:
There should be 0 V with the Pedal
pushed and battery voltage with
the pedal released.
'Faulty brake switch
. An open In the wlre
3BLKU nderall conditionsCheck for continuitY to groundl
There should be continuity
' Poor ground (G401, G402)
. An open in the wire
5GRNA,A/HT
Brake pedal pushed,
then released
Check for voltage to groundl
There should be batterY voltage
with the Pedal Pushed. and 0 V
with the pedal released
. Blown No. 52 (15 A) fuse in the
under-hood fuse/relaY box
. Faulty brake switch. An open in the wire
LT GRN/
RED
Set button pushedCheck for voltage to ground:
There should be batterY voltage.
Blown No. 52 (15 A) fuse in the
under-hood fuse/relaY box
Faulty horn relay
Faulty sevresume switch
Faulty cable reel
An open in the wire7LT GRN/
BLK
Resume button Pushed
10RED/BLU
lgnition switch ON (ll)Attach to ground:
Cruise indicator light in the gauge
assembly should come on.
Blown bulb
Blown No. 25 (7.5 A) fuse in the
under dash fuse/relay box
Faulty dimming circuit in the
gauge assemDly
An open in the wire
BLU,A/VHT
lgnition switch ON (ll)
and main swilch ON;
raise the front of the
car, and rotate one
wheel slowly with the
other wheel blocked.
Check for voltage between the
BLUMHT @ and BLK O terminals:
There should be 0- 5 V or more
-0- 5 V or more repeatedlY
. Faulty vehicle speed sensor {VSS)
. An open in the wire
LT GRN
lgnition switch ON (ll)
and main switch ON
Check for voltage to ground:
There should be batterY voltage.
Blown No. 14 (7.5 A)fuse in the
under-dash luse/relaY box
Faulty main switch
An open in the wire
14PNK
A,T: Shift lever in E,
ojorE
M/T: Clutch pedal
released
Check for continuity to ground:
There should be continuity.
NOTE: There should be no conti-
nuity when the clutch Pedal is
depressed or when the shift lever
is in other positions.
Faulty A/f gear position switch
Faulty or misadjusted clutch
switch (M/T)
Poor ground (G401, G402)
An open in the wire
BLU/GRN
Under all conditionsCheck for continuity between No. I
terminal and No. 5 terminal of the
PCM connector A.
There should be continuity
. An open in the wire
*: '99 - 00 models with A,/Tl-,
23-243

Circuit Diagram
UNDER-HOOD FUSE/RELAY 8OXIGNITIONSWITCH
WHT/8LI( +WHT
Brake systsm light
passenger's airbag
l----ltlI DUMMY II BESISTOR I
tll
tl
la rl
MEMORY ERASESIGNAT IMES)CONNECTOR I2P)
GRY{GRN)
I
BRN BRN
tl.-l- .-r-\./ \./
ECM/PCM SERVICECHECKCONNECTOR
ILT 8LU
I
t'7
DATA LINKCONNECTOR{DLC) {r6P)
GRY GRY(GRN) IGNN)
V:
G801
Teminalside oi thal€ terminals
24-6
4''
SRS UNIT TERMINALSG40tG402
SBS INDICATOR CIRCUIT{ln the gauge assembly)
PGM_FI
DRIVER'SAIRBAGINFLATOR
10 14 r 13 6 7(VAl 3{VBlSRS UNIT16 17 t5 9 18 8

Troubleshooting
The SRS Indicator Light Doesn't Come On
CAUTION: Whonever ths ignition switch is ON {ll}, or
has been turned OFF tor less than three minutes. be
careful not to bump the SRS unit; the airbagls) could
accidentally deploy .nd caus6 damage or iniuri€s.
Check tho pow€r supply (fuse):
Turn the ignition switch ON (ll), and check whether the otherindicator lights come on (brake system, etc.).
Oo the other indicator liohts como on?
YESNO
Check th6 fuso:Check the No. 25 {7.5 A) fuse in the under-dash tuse/relayb"t
ls th6 tu36 OK?
NOYES
Check the bulb:Replace the No. 25 (7.5 A) fuse, and check that theSRS indicator light comes on.
Doos the SRS indicator liqhl come on7
I YES No
END
Check tho wire harns b€twecn fus6 and gauge aasambly:Check for an open in the wire harness between luseNo. 25 {7.5 A) and the gauge assembly, and repair. Checkthat the SRS indicator light comes on.
Doo. tho SRS indic.tor light como on?
I yEs No
I
END
Check tho SRS indicator light bulb:1. Turn the ignition switch OFF.2. Remove the gauge assembly.3. Check for blown SRS indicator light butb.
ls the SRS indicator light bulb OK?
NOYES
Ch.ck the SnS indicator liglrt circuit:Replace the bulb, and reconnect the gauge assemblyconnectors. Then turn the ignition switch ON {ll}.
Ooes th6 SRS indicato. llght come on?
I YEs No
:ND
lAl To page 24-27
24-26
lB'J fo page 24-27
))
No. 25 (7.5 Al FUSE

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

Fuse
NumberFuse NameAmpsPage
BATTERY
Component or Circult Protected
Power distribution
lgnition switch
INTERIOR LIGHT | 7.5 | 10-10 | DLC, Ceiling light, Trunk light
FI E/M15 i(20 GX) i
i PGM-FI main relay, Fuel injection relay (GX)
Not used
POWER WINDOW| 10-10 | Power window relay
BACK UPStereo radio iuner ('9G'98 mod€ls), Audio unit ('99100
models), Heater control panel, PCM/ECM, TCM (9e'98
cvr)
HEADLIGHT
REAR DEFROSTER I
DOOR LOCK UNIT,
ROOF
i 10-12i Headlights
Not used
Rear window defogger relay
Power door lock control unit (all except '99-'00 models
with keyless), Keyless door lock control unit ('99-'00
models with keyless), Moonroof
i HORN, SrOP Lri 10-13i Horn relay, Brake switch
HAZARDHazard warning switch
OPTIONI 10-13I Security system (option)
i HEATER MOTOR Ii 10-1 i Blower motor relay
(CONDENSER FAN)
COOLING FANl1o-1
Condenser Jan relay, A'lC compressor clutch relay
Radiator tan relay
&5

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

Ground
G402
Components or Clrcult Grounded
Arr gear position switch, ABS control unit (3 wires), Blower motor high relay ('99-'00
models), Blower motor relay, ELD unit, Heater Jan switch ('96-'98 models), Heater
control panel, Mode control motor ('96.98 models), Power transistor ('99-'00 models),
Service check connector....plus everything grounded through G401
| 14-13 | ABS pump motor
1l-9 i Stereo radio tuner ('96-'98 models), Audio unit ('99-'00 models)
Drivsr's door lock actuator, Driver's door lock switch, Drivefs window motor' Left mirror
defogger, Pow€r window master switch (2 wires), Power door lock control unit (all
except '99-'00 with keyless), Power mirror switch
G55214-9 i Driver's s€at belt switch, Fuel pump, Fuel tank unit, Right mkror defogger
G601
(Hatch-
back)
14-12 iLeft and right back-up lights, Left and right brake lighvtail lights, Lefl and right rear
turn signal lights, Left and right tail lights....plus eveMhing grounded through G761
G601 I 14-10
(All Coupesl
ano
(96198
S6dans)
High mount brake light, Left and right back-up lights, Left and right inner brake lighv
taiilights, Lett and right license plale lights, Lett and right outer brak€ lighvtail lights'
Left and right rear turn signal lights, Rear window deJogger, Trunk latch switch
G601
(99-'oo
Sedans)
G602
('ss-'00
Sedans)
G761
(Hatch-
back)
G771
(Hatch-
back)
14-11
14-12 i
High mount brake light, Left and right back-up lights, Left and right brake lighvouter
taillights, Left and right inner taillight, Left and right rear turn signal light' Rear window
deJogger (GX), Trunk latch switch
Window antenna coil
Hatch latch switch ('98-'00 models), High mount brake light' Left and right license plate
lights, Rear window wiper motor...plus everything grounded through G601
Rear window defogger
14-13 i SRS unit (2 wires)
*1 = All '96-98 models €xcept Dl685, '99100 D16Y5 with M/T*2 = '98 D1685, all '99-'00 models except Dl6Y5 with M/T
e7

Ground Distributioh (conrd)
)
- G401
NOTE:
To G402on page14-5.
WINOSHIELOWIPERMOTORPage 91-1
DAYTIMERUNNINGLIGHTS
99.!rRoL cLUrcHuNr I swtTcH:?99^ Pases 23-5and 34-3vtEw 66 PHA|A 55
I
I
INJECTORCONTROLMODULEPage 25-1
I
I
3
. Wires shown without color codes are black.
o On Coupe and Sedan models, G401 is represented by ring terminals.
tl
tl
INTER.LOCK6611p99 PARKUN|T PINpaoe j38 SWITCHor ige_t Page 138PHoro6s of 138-1vtEw 26 PHOfO /7r-1 r-'t
tttl
CLUTCHINTER-LOCKSWITCHPage 21-2
ll
ll
ttl
rll
I
Itttl
'Ll;
I
n
t
M/T with 01685Cruise/D16Y5enginewith M/T
BRAKEFLUIDLEVELswtTcHPage 71ot 71-1
tl
tl
DOOR LOCK .CONTROLSTEERINGLOCKPage /3
tl
tl
UNITPage 130-12 ;
ttl
tt:
models
RNte 40
I
I
(
I
I czor
l'i1l?,
'97 mo
HORNPage 4
I
I
NFnl
s 9c.Plv'
BLK/RED
t
IJ;--
',f-l
DATA LINKCONNECTOR(DLC)Pages 23-4,24-4,25 4,44-1, and 47
30
14-6
G401