1998 HONDA CIVIC Model

Air Mix Gontrol Motor
't.
Test -'99 - 00 Models
Disconnect the 5P connector from the air mix con-
trol motor.
Connect battery power to the No. 1 terminal of the
air mix control motor, and ground the No. 5 termi,
nal; the air mix control motor should run, and stop
at MAX HOT. lf it doesn't, reverse the connections;
the air mix control motor should run, and stop at
MAX COOL.
lf the air mix control motor does not run, remove
it, then check the air mix control linkage and
doors for smooth movement.
lf they move smoothly, replace the air mix con-
trol motor.
AIR MIX CONTROL MOTOR
Measure the resistance between the No.2 and No.3
terminals. lt should be approximately 4.8 to 7.2 kO.
Measure the resistance between the No. 2 and No. 4
terminals. lt should be approximately 3.84 to 5.76 kO
at MAX HOT and approximately 0.96 to 1.44 kO at
MAX COOL.
21-46
5P OONNECYOB
Replacement -'99 - 00 Models
1, Disconnect the 5P connector from the air mix con-
trol motor. Remove the self-tapping screws, the airmix control motor and the flange collar.
CONTROLMOTOR
Install in the reverse order of removal. After installa-
tion, make sure the air mix control motor runs
smoothly.

RelaysHeater Fan Switch
Test
There should be continuity between the No 1 and No. 3
terminals when power and ground are connected to the
No.2 and No. 4 terminals, and there should be no conta-
nuity when power is disconnected.
Blower motor relaY
. Blower motor high relay ('99 00 models)
,I It;€'Y )
Test -'96 - 98 Models
Check for continuity between the terminals according to
the table below.
lerminal
Position14253
OFF
1IrJ
2o-o
3o-a
4c)-{
21-49

Mode Control SwitchPower Transistor
Test -'96 - 98 Models
Check for continuity between the terminals accordinq tothe table below.
Terminal
Position't071
Heato-o
HeaVDefo---o
Defo--o
VentG-o
HeaVVento--o
1
;l t
4
789
21-50
Test -'99 - 00 Models
1. Disconnsct the 3P connector from the oower tran-stsror.
2, Carefully release the lock tab on the No. 2 terminal inthe 3P connector, then remove the terminal and insu-late it from body glound.
Connect a 1.2 - 3.4 W bulb between the No. 1 andthe No. 2 cavity on the 3P connector.
Reconnect the 3P connector to the power translstor.
Turn the ignition switch ON fll), and check that theblower motor runs.
12V 1.2-3,1W
No. 1 laLU/aLK)

Air Conditioning
Speciaf Tools ......'.....' 22-2
f f f ustrated f ndex ......................... ".......' 22-3
Wiring/Connector Locations'.........'.... 22'4
Description
Outfine ............ .......22-s
Circuit Diagram
'96 - 98 Models ......"..........".......'.... 22-6
'99 Modef """""""' 22-7
Troubleshooting
Symptom Chart ".'......""................. 22-8
Flowcharts
Condenser Fan .........".................,..'. 22-9
Compressor .....""" 22-12
A/C System .........'.22'17
A/C Thermostat
Test ........'.......' """'22'21
Relays
Test ....."'......... ..""'22-21
A/C Service Tips and Precautions ......22-22
A/C System Torque Specifications '...22-23
A/C System Service
Performance Test ... '."......... ".... ....'..22-24
Pressure Test Chart .................. .... "' 22-26
Recovery ...".........," 22-27
Evaporator
Replacement .....",' 22'24
Overhauf .....-.....""' 22'29
Compressor {SANDEN}
Repf acement ......'.' 22-30
fffustrated fndex ......"..................'.... 22'32
Cf utch Inspection ......... "............ ...... 22-33
Clutch Overhau I ........................ ....... 22-34
Thermal Protector Replacement .... 22-36
Relief Valve Replacement ......'..."". 22-36
Compressor (DENSO)
Repfacement ..""',' 22-37
lf lustrated Index ............................... 22-39
Clutch lnspection ............."'...... "'.... 22-40
Cf utch Overhaul .....................'......... 22-41
Ref ief Valve Replacement'..'......"'.. 22-42
A/C Compressor Belt
Adiustment ............22'43
Condenser
Repfacement .......,,22'44
A/C System Service
Evacuation ...,,,.......22-45
Charging '..........--'..22'46
Leak rest """""""'22-46

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

Troubleshooting
Gompressor (cont'dl
'96 -98 models:
ECM/PCM CONNECTOR C 13lPI
Wire side ot female terminals
'9!t - 00 mod.bi
ECM/PCM CONNECTOR A I32P)
Wire side ot female terminals
*How to use the backprobe setsConnect the backprobe adapters to the stacking patch cords, andconnect the cords to a multimeter. Using the wire insulation as aguide for the contoured tip of the backprobe adapter, gently slidethe tip into the connector from the wire side until it comes in con-tact with the terminal end ofthe wire {see section 11}.
From page 22-15
Check for an open in thg wire:'1. Reconnect the A"/C pressure
switch 2P connector.2. Make sure the A/C switch isOFF, then turn the ignitionswitch ON (ll).
3. Using a *Backprobe Set {T/N07SAZ - 001000A), measurethe voltage between the No. 5terminal of the ECM/PCM con-nector C (31P) and bodyground with the EcM/PcMconnectors connected ('96 -
98 models), or between theNo. 27 terminal of theECM/PCM connector A (32P)
and body ground with theECM/PCM connectors connected ('99 - 00 models).
Rapdir open in tho wi?e botwaonthe A/C pr..-ruro lwitch rnd th.ECM/PCM.
Check lor loo3e wires or ooolconnections at the ECM/PCMconnectoB A l32P) and at the A/Cpressure switch 2P connector, lfthe connections are good, substi-tute a known-good ECM/PCM,and recheck. lf the svmptom/indication goos away, repbce theoriginal ECM/PCM.
31501E91011
tat6l11E1921222321
BLU/RED
22-16