1996 HONDA CIVIC ac clutch circuit

Power Distribution
Circuit ldentification (conf dl
IM/T)
rGNrTtoN swrTcH (sT)(From pag€ 23{9)
YBLK ,VHT
t-
I
r**"'.fffr,u,r.*@**-_
lil.BLT(-^,I'/HT -|:1jl- BLT(RED
T
BLK ^/HT - $aner sol€ndd G401
STAFTERCUT RELAYCLUTCH SWITCH
BLIVREO
L-
rGNrTroN swtTcH (sT){From paoe 23{9)
f'7
IIBLK/WHT
NEUTFAL POSITIONswtTcH/ln lL/Tgeat \\posnion swldr/
BLT(RED
-BLK4rrHr
- srarrer sotsnoid
(Fus€felay lox sockol)lrflagGt€d conlrol unit
ELU VHT - PGM-F| main retay
BLUMHT _ ECI\T/PCM
lH#|1'#i,'f,5>-**l e ock connol unit(via intedocf switdr)
Key ints ocl solenoid
23-72
wHr + &3T:$111.9|'ij""'n'"

Starting System
Starter Test lcont'dl
Ch€ck tor Wear and Damage
The starter should crank the engine smoothly and
steadily, lf the starter engages. but cranks the engine
erratically, remove it, and inspect the starter drive gear
and torque converter or flywheel ring gear for damage.
. Check the drive gear overrunning clutch for binding
or slipping when the armature is rotated with the
drive gear held,- lf damaged. replace the gears.
Check Cranking Voltsge and Curr€nt Draw
Cranking voltage should be no less than 8.5 volts.
Current draw should be no more than 350 amperes.
lf cranking voltage is too low, or current draw too high,
check for;
. dead or low batterv.
. open circuit in starter armature commutator seg-
ments,
. starter armature dragging.
. shorted armature winding.
o excessive drag in engine.
Check Cranking rpm
Engine speed during cranking should be above 100 rpm,
lf speed is too low, check for:
. loose battery or stanerterminals.
. excessively worn starter brushes,
. open circuit in commutator segments.
o dirty or damaged helical spline or drive gear.
. defective drive gear overrunning clutch.
Check Siarter Disengag€ment
With the shift lever in El or @ position (A/T) or with the
clutch pedal depressed (M/T), turn the ignition switch to
START (lll), and release to ON (ll).
The starter drive gear should disengage from the torque
converter or flywheel ring gear when you release the
Key.
lf the drive gear hangs up on the torque converter or fly-
wheel ring gear, check for:
. solenoid plunger and switch malfunction,
. dirty drive gear assembly or damaged overrunning
clutch.
Starter Solenoid Test
1. Check the hold-in coil for continuitv between the S
terminal and the armature housing (ground). The
coil is OK if there is continuitv,
ARMATUREHOUSING(GROUND)
S TERMINAL
M TERMINAL
B TERMINAL
STARTERCAELE B TERMINALMOUNTING NUTI N.m {0.9 kgf.m,7 tbf.ft)
Check the pull-in coil for continuity between the S
and M terminals. The coil is OK if there is continuity.

)
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

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

- Manual Transmission
NOTE: For cars equipped with optional security system, see Security System, page 133-3, or 133-7, or 133-12
for starting system circuit schematic.
Starting System
c3s2PHOTA 8vtEw 27
WHT/BLKc415
FUSE 42to!a0a
UNDER-HOODFUSE/RELAYBOXI
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IELECTBICALIOADDETECTOR(ELO) UN|TPtloro I
Sae Po'/Y€rDislibution,pag€ 10.------JT1
Se6 GroundDislribution,page 14-6.
BATTERY
STARTERCUTRELAY
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a
BLK/FED
9
BLKAVHT
ct01
vlEW 2A
c4't9
vtEw 49
FUSE 31STAATER SICIIAL7.5A
STARTER
4
Sse PGM-FI,page 231ot 2+1.
UNDER-DASHFUSE/RELAYBOX
At3
tl
tl
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cLUrcH TNTERLOCK tClosed wrlh clutch pedal Ifully depressed. llPHoro 1ra I"**"
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Se€ PowerDistibution,page 10.
4('98100 models 3)ALU/BLK
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21-2
I- G1

Gruise Control (cont'd)
- How the Circuit Works
The cruise control system uses mechanical and
electrical devices to maintain the car's sDeed at a
setting selected by the driver.
System Description
The cruise control unit receives command signals
from the crurse control main switch and the cruise
control SeVResume switch. With the ignition switch
in ON (ll) or START (lll), voltage is provided to the
cruise control main switch through fuse 14. When
you push the switch to ON, power is provided to the
cruise control unit and the brake switch.
The cruise control unit receives information about
operating conditions from the brake switch, the
vehicle speed sensor (VSS), and the clutch switch
(manual transmission) or the A,/T gear position
switch (automatic transmission). The cruise control
unit then sends signals to the cruise control actuator
which regulates the throttle position to maintain the
selected speed. The conlrol unit compares the
actual speed of the car to the selected speed. The
control unit then uses the result of that comoarison
to open or close the throttle.
The brake switch releases the system's control of
the throttle at the instant you press on the brake
pedal. The switch sends a signal to the control unit
by removing power from the normally closed brake
input (GRY wire), and providing power at the
normally open brake input (GRN/vVHT wire). The
control unit responds by allowing the throttle to
close. The clutch switch or the A,/T gear position
switch sends a "disengage" signal to the control unit
that also allows the throttle to close.
The cruise control system will set and automatically
maintain any speed above 25 mph (40 km/h). To set
it, make sure the main switch is on and the switch
indicator is on. Then, after reaching the desired
speed, press the SET switch. This sends a "set"
signal to the cruise control unit which, in turn,
controls the cruise control actuator to maintain the
set speed.
When you push the SET switch and the cruise
control system is on, the "cruise control" ON
indicator lights up.
34-4
(
You can cancel the cruise control system by
turning the main switch off . This removes power to
the control unit and erases the set speed from
memory. lf the system is disengaged temporarily
by the brake switch, or clutch switch, and the car's
speed is still above 25 mph, press the resume
switch: the car will automatically return to the
previously set speed.
For gradual acceleration without pressing the
accelerator pedal, push the RESUME switch and
hold it there. This will send an "acceleration" signal
to the control unit. When you release the switch, the
system will be reprogrammed for the new speed. To
slow the car down. oush the SET switch in and hold
it there. This sends a "deceleration" signal to the
control unit, causing the car to coast. When the
desired speed is reached, release the SET switch.
This reprograms the system tor the new speed.
Refer to the Service Manual (Section 23, Electrical)
tor specific tests or troubleshooting procedures.
(
a

- How the Circuit Works
Battery voltage is supplied through tuse 56 to the
A,/C compressor clutch r€lay contacts at all times.
With the ignition switch in ON (ll), vollage is applied
to the coil of the A,/C compressor clutch relay
through fuse 17. When you push the A,/C switch
ON, and the heater fan switch is in position | , 2, 3,
or 4, a "ground" input is provided to the engine
control module (ECM) or powertrain control module
(PCM) through the l'lC thermostat and the l'lC
pressure switch.
The A,/C compressor clutch relay is grounded by the
engine control module (ECM) or powertrain control
module (PCM). When energized, the A'lC
compressor clutch relay allows battery voltage to
turn on the A,/C comDressor clutch.
The A,/C ON indicator light comes on when the A,/C
system is requested.
A,/C Thermostat
The A'lC thermostat is located on the evaoorator
housing. The A,/C thermostat turns off the A,/C
compressor clutch if the temperature at the
evaporator goes below 3'C (37'F). This prevents
condensation from freezing on the evaporator fins
and blocking the air delivery into the passenger
compartment. The blower motor will keep running
when the sensor turns off the comDressor.
A,/C Pressure Switch
The fuC oressure switch is located in the condenser
outlet line where refrigerant is in a high
temperature/high pressure liquid state. The switch
will sense abnormally high or low pressure, and
open the circuit. This removes ground, and the
compressor will stop running.
Thermal Protectot
The thermal protector, located on the A,/C
compressor, opens and turns the compressor off if it
senses high temperature. Once the compressor
cools, the switch will close and the compressor will
begin running again.
Refer to the Service Manual (Section 22,
Air Conditioning) for specific tests or
troubleshooting procedures.
62-3

- How the Circuit Works
Radiator Fan
Voltage is provided at all times to the radiator fan
relay (contacts) through fuse 57. With the ignition
swilch in ON (ll), voltage is provided to the coil of
the relay through luse 17.
The radiator tan relay can be grounded through
either the engine coolant temperature switch or the
engine control module (ECM) or powertrain control
module (PCM).
The engine coolant temperature switch grounds
the radiator fan relay (coil) when the engine
coolant temperature exceeds 199'F (83'C). The
switch opens when coolanl temperature
decreases 3'- 8'C.
Condenser Fan
Voltage is provided at all times to the condenser fan
relay (contacts) through fuse 56. With the ignition
switch in ON (ll), voltage is provided to the coil of
the relay through fuse 17. When you push the A'lC
switch and put the heater fan switch in 1, 2,3, o( 4
position, the ly'C thermostat comes on, the
condenser fan relay energizes, and the condenser
fan motor runs.
A,/C Thermostat
The A,/C thermostat is located on the evaporator
housing. The A,/C thermostat tums off the A/C
compressor clutch if the temperature at the
evaporator goes below 3'C (37'F). This prevents
condensation from freezing on the evaporator fins
and blocking the air delivery into the passenger
compartment. lf the temperature goes below 3'C
(37"F) tuming off the Ay'C thermostat, ground will be
removed from the condenser fan relay. This will
deenergize the relay and remove voltage from the
condenser fan motor causing the fan to stop running.
Reter to the Service Manual (Section 23, Eleckical)
for specific tests or troubleshooting procedures.
63-3