1998 HONDA CIVIC Power motor relay

Troubleshooting
ABS Pump Motor
Diagnostic Trouble Codo {DTC} 51-53r ABS pump Motor Diagnosis
YES NOTE: Short the PMR terminat to body
NOTE: Reinstall ground for a moment, and recheck the fuse.
the fuse if it is OK lf the fuse is blown, check for a short to bodyground in the MCK circuit.
AAS CONTNOL UNIT 22P CONNECTOR
7At0tl
1211192l22
PMR IYEL/RED} I JUMPERI WIRE
Wire side of female terminals
NO
NO
YES
NOTE: Reinstallthe fuse if it is OK.
NOTE: Short the PMF terminal to booyground for a moment, and recheck the fuse.lf the fuse is blown, check for a short to bodyground in the wire between the under-hoodABS luse/relaV box and pumD motor.
- With the ignition switch ON(ll), ABS indicator lighr doosnot go otf.- With tho SCS s€rvico conneetor conn€cted lsee page 19661,OTCa 51-53 aro indicated.
Check the MTR CHECK (7.5 A) fuse.
Repl.ce the fuse .nd recheck.
Replaco tho tuse and rocheck.
Rcphce th€ pump motor rol6y.
Check the pump motor powersource circuit:Turn the ignition switch ON (ll).
Ch€ck for a short to !'ows. in thopumP motor power 3ource ciacrrit:Remove th6 purnp motor relay,
Does the pump motor operate?
Bopair sho.t to powsr in the wir€botwoen the under-hood A8Stuse/.elay box and ABS pumpmotor.
Does the pump motor operate?
Check tor loGe ABS control unitconnoctors. lf nocessary, substi-tute a known-good ABS controlunit and roch€ck,
(To page 19-69)
19-68

Heater
lllustrated Index
'96 - 98 Models ................................ 21'2
'99 - 00 Models ................................ 21'3
Circuit Diagram
'96 - 98 Models .....21-4
'99 - 00 Models ................................ 21-5
Troubleshooting - '96 - 98 Models
Symptom Chart ............................... 21-6
Heater Control Panel Input/
Output Signals ..............,.............. 21-7
Flowcharts
Blower Motor Speed ................... 21-8
Bf ower Motor ,...21'10
Mode Control Motor ............... ,.'.' 21-13
Recirculation control Motor ....... 21-16
Heater Control Panel ................ ... 21 -14
Troubleshooting - '99 - 00 Models
Symptom Chart ............................... 21-19
Seff-diagnosis Function ............,,,.... 21-20
Flowcharts
Air Mix Control Motor ......,.......... 21-21
Mode Control Motor ............... ..... 21 -25
Recirculation Control Motor ....... 21-27
Bf ower Motor Speed .............. .....21'29
Bf ower Motor ....21-31
Heater Control Panel ................,.. 21-35
Heater Control Panel Input/
Output Signals ............................. 21-36
Blower Unit
Repf acement .........21-37
Overhaul ................ 21-38
* Heater Unit
Replacement ....'....21-39
overhaul """" """' 21-4'l
Heater Control Panel
Repfacement .........21'42
Overhaul -'96 - 98 Models ........... 21-43
Temperature Control
Adjustment - '96 - 98 Models """" 21-44
Adiustment - '99 - 00 Models .......21-45
Air Mix Control Motor
Test - '99 - 00 Models ...........' .......21'46
Replacement - '99 - 00 Models ....21'46
Mode Control Motol
Test ................, .,...'.21'47
Replacement '.'."...21-47
Recirculation Control Motor
Test ................. .......21-48
Repf acement ......." 21-48
Relays
Test ................. .......2'l-49
Heater Fan Switch
Test - '96 - 98 Models ............. .......21-49
Mode Control Switch
Test -'96 - 98 Models ..........."....... 21-50
Power Transistor
Test - '99 - 00 Models ....'........ ....".21-50
*: Read SRS Drecautions before working in this area.

'99 - 00 Models
SRS components are located in this area, Review the SRS component locations, precautions, and procedures in the SRS
section (24) betore perfoming repairs or service.
HEATER UNITReplacement, page 21'39
Overhaul, page 21-41
BLOWEB UNITReplacement, page 21-37Overhaul, page 21 38
HEATER FANswtTcH
RECIRCULATIONCONTROL MOTORTest, page 21-48Beplacement, page 21-48
AIR MIX CONTROL MOTOBTest, page 21-46Replacement, page 21 46
BLOWERTest, page 21-49
POWER TRANSISTORTest, page 21 50
HIGH RELAY
MODE CONTROLDIALHEATER VALVE CABLEAdjustment, page 21 45TEMPERATURE CONTROLDIALAdjustment, page 21-45
REAR WINDOWDEFOGGERswtrcHSee section 23MODEMOTORTest, page 21 47Replacement, page 2 l-47A/C SWTTCH
lwith A/cl
CONTROL SWITCH
21-3

Mode control motor does not run.
or one or more modes arc inope]a-
tive.
Check the No. 17 (7.5 A) fuse in
the under-dash fuse/relay box.
Replace the Iuse. and recheck.
Check for an open in the wire:
1. Disconnect the mode control
motor 7P connector,
2. Turn the ignition switch ON (ll)-
3. MeasLrre the voltage between
the No. 1 terminal of themode control motor 7P con
nector and body ground
Repair open in the wire between
the No. 17 luse and lhe mode
control motor.ls there battery voltage?
Check the mode control motor:
1- Turn the ignition switch OFF
2, Test the mode control motor(see page 21 47).Check lhe mode control linkage
and doors:1. Remove the mode controlmotor (see page 21 47).
2. Check the mode control linkage
and doors for smooth move
ls the mode control motor OK?
Do the mode control linkage
and doors move smoothlY?
ReDlace the mode control motor'
Check for a short to Power in the
wires:1. Iurn the,gnitjon switch ON(ll).
2, Disconnect the heater controlpanel20P connector.3. Check for voltage betweenthe No. 2, 5, 6, 7, I and 9 ter'minals of the heater controlpanel 20P connector andbody ground individuallY.Repair shorl to power in the
wire{sl between the heater con-
trol oanel and the mode controlmotor. This short also damagesthe heater control Pan6l. RePair
the short to power before replac'ing the heater control Panel
ls lhere any voltage?
MODE CONTROL MOTOR 7P CONNECTOR
t2315
BLK/YEL
Wire side of female terminals
HEATER CONIROL PANEL 2OP CONNECTOR
Wire side of female terminals
NO
(cont'd)
21-25Io page 21 26

Troubleshooting -'99 - 00 Models
Heater Control Panel Input/Output Signals
HEATER CONTROL PANEL CONNECTORS
8P CONNECTOR2OP CONNECTOR12P CONNECTOR
Wire side of female terminals
8P CONNECTOR (O qn Circuit Diagram)
20P CONNECTOR {D on circuit Diagram}
*: with Ay'c
12P CONNECTOR (tr on Circuit Diagraml
CavityWire colorSignalCavilyWhe colorSignal
BLU/8LKBLOWER FEEDBACKINPUT5REDDASH LIGHTS BRIGHTNESSCONTROLLEROUTPUT
2GRN/lVHTFRESHINPUT6BLKGBOU N DOUTPUT
3GRN/REDRECIRCULATEINPUT7BLU/YELREAR WINDOW DEFOGGERRELAYOUTPUT
4RED/BLKCOMBINATION LIGHT SWITCH(Via No. 30 (7.5 A) fuse)INPUT88LfiELlG2 {Power)INPUT
CavityWire colorSignalCavityWire colorSignal
LTGRN/BLKPOWER TRANSISTOR EASEOUTPUT't1BLU/REDAy'C THERMOSTATINPUT
2BRNMHTMODE CONTROL MOTORGROUNDINPUT12BRNAIR MIX CONTROL MOTORGROU NDINPUT
3RE D/YELAIR MIX HOTOUTPUT13ORNAA/HTBLOWER MOTOR HIGHRELAYINPUT
RED,ryvHIAIR MIX COOLOUTPUT14
5YEUBLUMODE DEFINPUTPN K,/BLKAIR MIX POTENTIALOUTPUT
6YEUREDMODE VENTINPUT16
7GRNI/ELMODE HEAT/r'ENTINPUT11
IBLUAVHTMODE HEATINPUT18
9YELMODE HEAT/DEFINPUT19
10WHT/BLU+B (Power)INPUT20GRYAIR MIX POTENTIAL +5 VOUTPUT
CavityWilecolorSignalCavityWi.e cololSignal
lSWITCH LED COMMONOUTPUT1SWITCH LIGHTS +OUTPUT
2ISWITCH LIGHTS -INPUT
39SWITCH COMMONINPUT
4RECIRCULATION CONTROLSWITCH LEDINPUT10A,/C SWITCHOUTPUT
5A./C SWITCH LEDINPUT11RECIRCULATION CONTROLSWITCHOUTPUT
6REAR WINDOW DEFOGGERSWITCH LEDINPUT12REAR WINDOW DEFOGGEBSWITCHOUTPUT
21-36

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

Connector ldentification and Wire Harness Routing
Connector or
Terminal
Number of
CavitiesLocalionConnec{s toNotes
T,I
r2
Right side of engine compartment
Right side of engine compartment
Under-hood fuse/relay box
Starter motor
BatteryBattery positive terminal
Starter Cables
A/C Wire Harness
Battery Ground Cable
Connector or
Terminal
Number of
CavitiesLocationConn€cts toNotos
Right front shock towerBody ground, via battery ground
caDte
oBafteryBattery negative terminal
Engine Ground Cable A
Conn€qtor or
Terminal
Number ot
CavitiosLocationConnects toNoles
T3Left side of enginePower steering pump bracket
G2Left side of engine compartmentBody ground, via engine ground
cable A
Engine Ground Cable B
Connector or
Terminal
Number of
CavitiesLocationConnecls toNoles
T4Right side of engine compartmentTransmission
Right side of front frameBody ground, via engine ground
cable B
Under-hood ABS Fusa/Relay Box Wire Harness
Connector or
Tgrminal
Number oI
CavitiesLocationConneqts toNotes
T5Right side of engine compartmentUnder-hood fuse/relay box
@BaneryBattery positive terminal
Connector or
Terminal
Number of
CavitiesLocationConnects toNotes
c753
c754
1
2
Right side of engine compartment
Right side of engine compartment
Right side of engine compartment
Right side of engine compartment
Engine compartment wire harness(c209)
Compressor clutch
Condenser fan motor
A,/C pressure switch
Left side of engine compartmentBody ground, via A,/C wire harness
23-14

Connector ldentification and Wire Harness Routing
Roof Wire Harness (Coupe/Hatchback)
Connector ol
Terminal
Number of
CavitiesLocationConnects toNotes
c701
c701
c702
c719
2
6
2
1
Under left side of dash
Under left side of dash
Middle of roof
Front of roof
Main wire harness (C407)
Main wire harness (C407)
Ceiling light
S potlig ht*1: '96 - 98 models*2: '99 - 00 models
Roof Wire Harness (Sedanl
'96 - 98 models'99 - 00 models
*1: '96 - 97 models"2: '98 model*3: '99 00 models
*l:
+2:
Connector or
Terminal
Number of
CavitiesLocationConnects toNotes
c701
c701
c702
c703
c719
2
1
1
1
Under left side of dash
Under left side of dash
Middle of roof
Middle of roof
Front of roof
Main wire harness (C407)
Main wire harness (C407)
Ceiling light (Power)
Ceiling light (Ground)
Spotlighr
Moonroof Wire Harness {Coupe/Sedan}
Connector or
Terminal
Number ot
CavitiesLocationConnects toNotes
c711
c711
c1't2
c713
c713
c714
c714
c715
c117
c718
c719
2
6
6
5
5
4
3
2
4
1
U nder left side of dash
Under left side of dash
Behind dashboard lower panel
Left side of dashboard bracketLeft side of dashboard bracket
Left side of dashboard bracket
Left side of dashboard bracket
Left side of steering wheel
Middle of roof
Rear of roof
Rear of roof
Front of roof
Main wire harness (C407)
Main wire harness (C407)
Under-dash tuse/relay box (C910)
Moonroof open relay
Moonroof open relay
Moonroof close relay
Moonroof close relay
Moonroof switch
Ceiling light
Moonroof motor
Moonroof motor (Tilt switch)Sporlight
Optional
23-54