1999 HONDA CIVIC Hood

Circuit Diagram
UNDER DASHFUSE/RELAY 8OX
N0.17 (7.54)
'96 - 98 Models
UNDER.HOOD FUSEi BELAY BOX
WHT/SLU BLKYEL
BLK
+
G751
3
'o
I8LK
I
G40lG402
GNITON SWITCH
N0.41 (8rA) N0.42 (40A)
COMPBESSORCLUTCHBELAY
BLUMHT
,l
(E) i,T'
BLUi BED
A/c ITHERMOSTAI BLU/REO
CONDENSEFFAN MOTOR
*F,.X,
FAN rl
BLK
{
G401G402
HEATERswrlcH
32
22-6

'99 - 00 Models
UNDER DASHFUSE/BELAY BOX
No.l7 (7.54)
BLK
I
G751
$*"
O :8P coNNEcToF
n :20P CONNECToF
E 12P coNNEcroRBLK
d-
G401G402
UNDER HOOD FUSE/RELAY 8OX
N0.41 (P,0A) N0.42 (404)
COMPRESSORCLUTCHFELAY
GNITON SWTCH
HEATER CONTROL PANEL
22-7

Troubleshooting
Symptom Chart
NOTE:
. Any abnormality must be corrected before continuing the test.. Because of the precise measurements needed. use a multimeter when testinq.. Before performing any troubleshooting procedures check:- Fuses No. 47 l7 -5 Al, No. 56 (20 A) in the under-hood fuse/relay box, and No. 17 (7.5 A) in the under_dash fuse/relavbox- Grounds No. c401, c402, G751- Cleanliness and tightness of alt connectors
SymptomRemedy
Condenser fan does not run at all.Perform the procedures in the flowchart {see page 22-9).
Compressor clutch does not engage.Perform the procedures in the flowchart lsee page 22-12).
Ay'C system does not come on (compressor and fan),Perform the procedures in the flowchan (see page 22-17).
Both heater and A,/C do not work.. '96 - 98 models-Perform the procedures in the flowchart
{see page 21-18).. '99 - 00 models-Perform the procedures in the flowchart(see page 21-35).
22-8

Condenser Fan
CONDENSER FAN RELAY 4P SOCKET
JUMPERwlRE
(cont'd)
22-9
Conden3er fan does not run at all.
Check the No. 56 (20 A) fuse in the
unde.hood frJse/relaY box, and the
No. 17 (7.5 A) fuse in the under-
dash fuse/relay box.
Reolace the fuse{s), and techeck
Remove the condenser lan rclaY'
and test it (see page 22 21i
Replace the condensei fan relav.
Check the under-hood tus6/relaY
Measure the vohage between the
No. 2 terminalofthe condenser fan
relav 4P socket and bodv ground.
ls there battery voltage?
Check the condenser lan Powersupply circuit:Connect the No. 1 and No. 2 teF
minals of the condenser fan relay
4P socket with a jumper wire
Does the condenser fan run?To page 22-10
Io page 22 11

Check the diode:1. Disconnect the iumPer wire
2. Remove the A/C diode from
the under hood fuse/relaY box
3. Check for current flow in both
directions between the A and
B terminals.
ls there current flow in onlY
one direction?
Chock for an open in the wire:
1. Turn the ignition switch ON(ll).
2. Measure the voltage between
the No. 2 terminal of the AJC
diode 2P socket and body
ground.
Repair opon in the wire betwe€n
the No. 17 luse and the A/c
diode.ls there battery voltage?
B()-=iFA
A/C DIOOE 2P SOCKET

Troubleshooting
Compressor
COMPRESSOR CLUTCH RELAY.P SOCKET
JUMPERWIRE
check the No. 56 (20 A) fuse in theunder'hood fuse/relay box, and theNo. 17 (7.5 A) fuse in the under,dash fuse/relay box.
Replace the fussls), and .echeck.
Remove the compressor clutchrelay, and test it {see page 22 21).
Check th6 und€r-hood tu3e/reby
Measure the voltage between theNo. 2 terminal of the compressorclutch relay 4P socket and bodyground.
Check the compressor clutchpow€r supply circuit:Connect the No. 1 and No. 2 termi-nals of the compressor clutch relay4P socket with a jumper wire.
Does the compressor clutch click?fo page 22-13
To page 22 14
22-12

A/C System
CONDENSER FAN RELAY 4P SOCKET
A/C system does not come on
{comDressor and fan).
Check the No. 56 fuse in theunder'hood fuse/relay box andthe No. 17 fuse in the under-dashfuse/relay box.
ReDlace the fus6{s}, and recheck.
Check for tn open in the wire:
1. Remove the condenser lanrelay from the u nderhood
luse/relay box.2. Turn the ignition switch ON {lli.3- Measure the voltage betweenthe No. 4 terminal of the condenser fan relav 4P socketand body ground.
Repair open in the wire between
the No. 17 fuse and the con-denser fan r6lay,
Check the under-hood fus€/r6laybox:Measure the voltage between the
No. 2 terminal of the condenser
fan relay 4P socket and bodyground,
YES
Io page 22-18
(cont'd)

A/C System Service
Performance Test
The performance test will help determine if the air con-
ditioner system is operating within specifications.
Use only service equipment that is U.L.-listed and is cer-
tified to meet the reouirements of SAE J2210 to remove
HFC-134a (R-134a) from the air conditioner system.
CAUTION: Exposure to air conditionor rofrigerant and
lubricant vapor or mist can irrilalo €yes, nose and
throat. Avoid breathing tho air conditioner rstrigerrnt
and lubricant vapor or mist,
lf accidental system discharge occurs, ventilate work
area before resuming service.
R-134a service equipment or vehicle air conditioner sys-
tems should not be pressure tested or leak tested with
compressed air.
@ some mixtur$ of air and R-134a have been
shown lo b9 combustible rt glgvatad pr€ssur63 and can
resull in tire 01 oxplosion causing inlury ot property
damage. Never uao compre33ed air to pressure t99t R-
134a ssrvico 6quipmsnt or vohicla air conditioner sys-
tems.
Additional health and safety information may be obtained
from the refrigerant and lubricant manufacturers.
'1. Connect a R-134a refrigerant recover/recycling/
charging station to the vehicle, as shown, following
the equipment manufacturer's instructions.
2. lnsert a thermometer in the center vent outlet.
Determine the relative humidity and air tempera-
ture,
Test conditions:
. Avoid direct sunlight.
. Open hood.
. Open front doors.
. Set the temDerature control lever or dial to MAX,
COOL, the mode control switch or dial on VENT
and the recirculation control switch on RECIRCU-
LATE.
. Turn the A,/C switch on. and the heater fan switch
on MAX.
. Run the engine at 1,500 rpm.
. No driver or passengers in vehicle
After running the air conditioning for 10 minutes
under the above test conditions, read the delivery
temperature from the thermometer in the dash vent
and the high and low system pressure from the A,/C
gauges.
Recovery/Rocycling/Charging Station
22-24