1996 HONDA CIVIC Gauge control unit

SRS Indicator Light Wire Connections
SRS Indicator Light Power Circuit
DASHBOARD WIRE HARNESS
To UNDER-DASHFUSE/RELAY BOX -
20P CONNECTOR
SRS Indicato. Light Control Circuit
To SRS UNIT
tI
SRS MAIN HARNESS
C41 1, C412 : Terminal sido of mdlo t6rminalsC501, C5O2, C508, C801. C802, C807 : Wi.6 sidc of fomalo t.rminals
MAIN WIBE HARNESS
BLU
C508 -+ To GAUGE ASSEMBLY
c41 1
To GAUGE ASSEMBLY
at
C501 : DASHBOARDWIRE HARNESS 2oP CONNECTORC508 : DASHBOARD wlRE HARNESS 5P CONNECTORC801 : SRS MAIN HARNESS 2P CONNECTORC807 : SRS MAIN HARNESS 18P CONNECTOR
C802 : SRS MAIN HARNESS 3P CONNECTORC412 : MAIN WIRE HARNESS 3P CONNECTORC41 1 : MAIN WIRE HARNESS 24P CONNECTORC502 : DASHBOARD WIRE HARNESS 24P CONNECTOR
GRY
OI
24-25

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
NumberAmpsPageFuse Name
(RR WIPER
RR WASHER)
i R HiL HIGH BEAM | 10
L H/L HIGH BEAM
| (PAIV RR-L)
i (P/vv RR-R)
(rGN CO|L)
10I (P,^/V AS)
Component or Circuit Protected
Not used
Not used
Rear wiper, Security system (option)
(Vehicles pre-wired for accessory security system)
'10r 1n-2
I
| 1 10-12i Right headlight, DRL control unit (Canada)
Lett headlight, DRL control unit (Canada)
I ro-rsSecurity system (option)
| 120-2 | Left rear window motor
Right rear window motor
lgnition coil ('98-'00 models except GX)
| 120-1 | Front passenger's window motor
i (PiW DH)| 20 1 12O I Driver's window motor
TURN LIGHTSHazard warning switch
FUEL PUMP
(SRS UNIT)
PGM-FI main relav, SRS unit
(cRUrsE CoNTROL)
/KtrVt trSS\
Stereo radio tuner ('96-'98 USA: LX, EX, and HX),
Cruise control main switch, Keyless door lock
control unit ('99-'00 models with keyless entry)
15ALTERNATOR
SP SENSOR
l-a10-4I ELD unit, Gauge assembly, TCM (96-'98 CW, PGM-FI
16I RR DEF RELAY7.510-8I Rear window defogger ('96-'98 models), ABS control
I unit. Power mirror switch ('99-'00 models except GX)
i-HEATER r/C
I RELAY
Power mirrors ('96-98 models and all GX models),
Air delivery, Blower controls, AilC compressor
controls, Fans
I (RUNNING LIGHT
I RELAY)
1 7.5 1
tl
I DRL control unit (Canada)
i BACK-UP LTGHTSi Back-up lights
(RUNNING LIGHT)DRL control unit (Canada)
I R H/L LOW BEAM'10 l11o-12Right headlight
I L H/L LOW BEAM | 101110-12 | Left headlight
(cont'd)
(SRS)SRS unit
6-1

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 (cont'd)
@
FUSE 24{PAr/ FELAY}{S/R RELAY)?
_____
s7
FUsE 25 IMETEF I-------r-----l rII\IA6JI r*r tttrecnlreo \-
| | lcoNrRoLUNlr \
I i iPaseTo \
I L__Jlj:p,l2uo II vtt|| bl
tf
lt.---l--- "---t I---r--'g- -------Jcs01 '16YC419
PHata'a ' a PHolo 6"vtEw 55 ' yEL a vtEw 49
:t
i;l-l-l. i
'ttlll
:rttl' L--J !-,J. SHIFT INTERLOCK .
: LocK coNTRoL ,
; SOLENOID UNIT' Page 138 Page 138 I' or 138-1 or 138-1I DHOTO 7- D4O|O 69I vtFW26
'AT ---------
.-- A/T --.
"..ij#j--
",li,,lii"lii-lii^,li".l-l
i------------::r::-:-::'::---::r:-:-:--T--------1
tl
tl
alt------- --------J
.I POWER
I wrNDow
1 RELAYj Page 120
uorlI
I
c501 17C420 11
r::1
I uorr I
ll
MOONROOFOPEN RELAYPage 122ot 122 1
r=?1
I uorr I
ll
MOONROOFCLOSE RELAYPage 122ot 122-1
vtEw 13
(Not (NotUsed) Used)
ABSCruiseControlShift-upInorcalor 'r _
t
GAUGE ASSEMBLYPages 80, 80-1, 80'2,80-3, 81, 89, and 89-1
10-6

Gauges (cont'd)
- How the Gircuit Works
When the ignition switch is in ON (ll) or START (lll),
battery voltage is supplied through fuse 25 to the
gauges in the gauge assembly.
Speedometer and Odometer
The odometer and soeedometer drive circuits
receive pulses from the vehicle speed sensor
(VSS). The pulse rate increases as the car
accelerates. The frequency and duration of these
input pulses are measured and displayed by the
speedometer, odometer and tripmeter.
Tachometer
The tachometer drive circuit receives pulses from
the ignition control module (lCM) in the distributor
assembly or the ECM/PCM. The solid-state
lachometer then displays these pulses as engine
speed. For each 200 pulses per minute from the
ignition control modul€ (lCM) or the ECM/PCM, the
tachometer displays 100 RPM.
Engine Coolant Temperature Gauge
The engine coolant temperature gauge has two
intersecting coils wound around a permanent
magnet rotor. Voltage applied to the coils, through
fuse 25, generates a magnetic lield. The magnetic
field, controlled by the coolant temperature sending
unit, causes the rotor to rotate and the gauge
needle to move. As the resistance in the sending
unit varies, current through the gauge coils
changes. The gauge needle moves toward the coil
with the strongest magnetic field.
The 6ngine coolant temperature sending unit's
resistance varies from about 137 ohms at low
engine temperature to between 3H6 ohms at high
temperature (radiator fan running).
Refer to the Service Manual (Section 23, Electrical)
for specific tests or troubleshooting procedures.
81-2
(
Fuel Gauge (All except cX)
The fuel gauge has two intersecting coils wound
around a permanent magnet rotor. Voltage applied
to the coils, through tuse 25, generates a magnetic
field. The magnetic field, controlled by the fuel
gauge sending unit, causes the rotor to rotate and
the gauge needle to move. As the resislance in the
sending unit varies, current through the gauge coils
changes. The gauge needle moves toward the coil
with the strongest magnetic field.
The fuel gauge sending unit's resistance varies
from about 2-5 ohms at full, to about 110 ohms at
empty. When you turn the ignition switch off, the
gauge remains at the last reading until you turn the
ignition switch to ON (ll) or START (lll) again,
Refer to the Service Manual (Section 23, Electrical)
for specific tests or troubleshooting procedures.
Fuel Gauge (GX)
The fuel gauge has two intersecting coils wound
around a permanent magnet rotor. Voltage applied
to the coils, through fuse 25, generates a magnetic
field. The magnetic field, controlled by the PCM,
causes the rotor to rotate and the gauge needle to
move. The PCM calculates the gas quantity in the
fuel tank by using the fuel pressure value detected
by the tuel tank pressure sensor and the fuel
temperature value detected by the fuel tank
temperalure sensor, and outputs the signal to the
gauge assembly. The gauge needle moves toward
the coil with the strongest magnetic field.
When you turn the ignition switch off , the gauge
remains at the last reading until you turn the ignition
switch to ON (ll) or START (lll) again. When the
PCM detects a malfunction with the fuel pressure or
temperature, or detects a gas leak, the PCM
reduces the fuel meter to 0.
Refer to the Service Manual GX Supplement
(Section 11 , Fuel and Emissions) for specific tests
or troubleshooting procedures.
a
a

Security System (cont'd)
Security System Does Not Work ln Any
Mode (CX, DX)
1. ls luse 54 (in the under-hood fuse box) OK?
Yes - Go to the next step.
No - Repiace the blown fuse, then go to the
next step.
2. ls the fuse in the securiiy in-line fuse holder OK?
Yes - Go to the next step.
No - Replace the blown fuse, then go to next
srep.
3. Does either fuse blow again?
Yes - Locate and repair the short.
No - Retest the system.
4. ls there battery voltage at terminal 10 of the
security control unit connector?
Yes - Go to the next step.
No - Locate the open in the wiring between
fuse 54 and the security control unit.
ls there continuity from terminal 13 ol the
security control unit connector to ground?
Yes - Replace the security control unit.
No - Locate the open in the wiring between the
securitv control unit and G401.
5.
133-18
Security System Does Not Arm (CX, DX)
1. Place the ceiling light in the center position.
Does the ceiling light come on, even with all the
doors closed?
Yes - Faulty door switch or short in wiring to
door switches.
No - Go to the next steo.
2. With the ignition switch in the ON (ll) position,
does the trunk open indicator in the gauge
assembly come on, even with the trunk closed?
Yes - Faulty trunk latch switch or short in the
BLU/BLK wire.
No - Go to the next step.
3. Does voltage at terminal 2 of the security control
unit connector change from battery voltage with
all doors closed, to less than 1 volt when any
door is ooened?
Yes - Go to the next step.
No - Repair the open in the terminal 2
(LT GRN/BLK or LT GRN/RED) wire.
Does voltage at terminal 3 of the security control
unit connector change from battery voltage with
the trunk closed, to less than 1 volt when the
trunk is oDened?
v]" - R"pt"." tne security control unit.
No - Bepair the open in the terminal 3
(BLU/BLK) wire.

Security System Does Not Arm
(HX, LX, EX, DX-V, Si)
1. With all the doors closed, do the doors lock
when you press the transmitter LOCK button?
Yes - Go to the next steo.
No - Go to Doors Do Not Lock With The
Transmitter, on page 130-11 ('96-98
models) or 1 30-18 ('99 models).
Check the trunk open indicator in the gauge
assembly. With the ignition switch in the ON (ll)
position, does the trunk open indicator come on
even with the trunk closed?
Yes - Faulty trunk latch switch or shod in
BLU/BLK wire.
No - Go to the next steo.
Does the voltage at terminal 2 of the security
control unit connector change from
approximately 5 volts with all doors closed, to
less than 1 volt when any door is opened?
Yes - Go to the next step.
No - Repair the damaged terminal 2
(LT GRN/RED) wire.
Does the voltage at terminal 3 of the security
control unit connector change from battery
voltage with the trunk closed, to less than 1 volt
when the trunk is ooened?
Yes - Go to the next steo.
No - Repair the damaged terminal 3
{BLU/BLK) wire.
Does the voltage at terminal 15 of the security
control unit connector change from battery
voltage the key is not in the ignition, to less than
1 volt when the key is in the ignition?
5.
o.
Yes - Go to the-next step.
No - Repair the damaged terminal 15
(BLU/RED) wire.
ls ihere approximately 5 volts at terminal 22 of
the security control unit connector?
Yes - Go to the next step.
No - Replace the security control unit.
7. ls there approximately 5 volts at terminal 12
('96-'98 models) or 14 ('99 models) of the
keyless receiver unit ('96-98 models) or the
keyless door lock control unit ('99 models)?'96198 modelsi
Yes - Replace the radio ('96-'98 models) or the
keyless door lock control unit ('99
models).
No - Repair the damaged WHT/BLK ('96-'98
models) or BLU/YEL ('99 models) wire
between the security control unit and the
radio ('96-98 models) or the keyless door
lock control unit ('99 models).
133-19