1999 HONDA CIVIC Interlock control unit

Interlock System
Control Unit Input Test
1. Disconnect the 8P connector from the interlock con-trol unit.
2. Inspect the connector and socket terminals to besure they are all making good contact.. lf the terminals are bent, loose or corroded, repairthem as necessary, and recheck the system.. lf the terminals look OK, make the followinginput tests at the connector.- lf a test indicates a problem, find and correctthe cause, then recheck the system.- lf all the input tests prove OK, substitute aknown-good control unit, and recheck the sys-tem. lf the check is OK, the control unit mustbe faulty; replace it.
NOTE: lf the shift lock solenoid clicks when theignition switch is turned ON {ll) and you step on thebrake pedal (with the shift lever in E), the shift locksystem is electronically normal; if the shift leve.cannot be shifted from E], test the Aff gear position
switch, park pin switch, and see section 14.
Key Interlock System:
CavityWireTest condition
Reconnect the 8P connector to the interlock control unit.
Shift Lock System:
Cavity WifsTest condition
INTERLOCKCONTROL UNIT
Test: Desired result
Test: Dgsired result
Wire side offemale terminals
Possible cause if result is not obtained
Possible cause if result is not obtained
WHT/BLU
lgnition switch turned toACC (lland key pushed inCheck for voltage to groundiThere should be baftery voltage.Blown No. 48 (30 A) fuse in the underhood fuse/relay boxBlown No. 33 (7.5 A) fuse in the underdash fuse/relay boxFaulty steering lock assemblylkey interlock solenoid)An open in the wire
5WHT
BLKUnder all conditionsCheck for continuity to ground:There should be continuity.
' Poor ground (G401, G402). An open in the wire
6BLK./BLUShift lever in ElCheck for continu;ty to ground:There should be continuity.Poor ground (G401, G402)Faulty Ay'T gear position switchAn open in the wire
2YELlgnition switch ON lll)Check for voltage to ground:There should be banery voltage.
. Blown No. 25 (7.5 A) fuse in the under,dash fuse/relay box. An open in the wire
3YEUBLK
lgnition swirch ON (ll)Check for voltage to ground:There should be baftery voltage.Blown No. 25 (7.5 A) fuse in the under-dash fuse/relay boxFaulty shift lock solenoidAn open in the wire
6BLI(BLUShift lever in ICheck for voltage to ground:There should be 1 V or less.Poor ground (G401, G402)Faulty A,/T gear position switchAn open in the wire
7WHT/RED
lgnition switch ON lll)Brake pedaldepressedCheck for voltage to ground:There should be 1 V or less.Blown No. 52 (15 A) Iuse in the underhood fuse/relay boxFaulty PCMFaulty brake switch (see section 1l)Faulty throttle position {TP) sensor(see section 1'l )An open in the wire
lgnition switch ON (ll)Brake pedalandaccelerator depressed atthe same time
Check for voltage to ground:There sho(Jld be battery voltage.
23-146

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

- '96-'98 CVT
l-l-'l BRAKE SWTTCH r--'l THROTTLE
| | lclosed wrlh I ..-. -, I PoslrloN
l&l!fii{+f i.:1r1'jflI$s"
o""*"tr[
"o'ouloo,
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jilll I lllb ;s"",
!
-
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+ | i.'*-w- - - - -,r-.1 j If$$Bi,
e* !;;iiffi :,?H,,, ry*:' !fi3$lt3'
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i-u;-*"--- ,s l [ltsff?.
Lj:'sri:--::l itjs[-
=ffan+'INTERLOCKCONTROLUNIT
vtEw 26
;-;5[ BLKBIUI BLKBTU See A/f Gearar< Positioni lndicator
NOTE:ln case of systemmalfunction, theshift lever can bereleased by pushingthe ignition key intothe release slot nearthe shitt lever.-------r A/T GEAR
il{t iffi'dqF"I l,'- -\-" l;#i;",;
l" i'-!
L---J.---JBLK I C433
"IYW!'" :."qsrqft
rE.===---- F-
Shltt Lock ClrcuilPrevents shift locksolenoid lrom€nergizing unleesbrake p€dal isdepressed andaccelerator pedal isnot depressed.
Key ldedockClrcultAllows k€yinterlocksolenoid tobe energizedunl6ss shittlever is in'P"
;;.r";;
ll e
138-1

-25. CW Transmission Solenoid
- Gray- Lower front of transmission- On engine wire harness
1
2 GRNAVHT (H LC LS +)
3 BLUAVHT (SH LS +)
4 YEL (SC LS +)
5
6
7
8
GRN/BLK (SOL IN H)
PNK/BLK (HLC LS _)
GRN|VEL (SH LS -)
PNK/BLU (SC LS _)
26. Interlock Control Unit
- Gray- Behind left side oJ dash, right of steering column- On main wire harness
1
7
2
3
4
WHT/BLU (Key interlocksolenoid control)
YEL (lgnition input)
YEUBLK (Shift locksolenoid control)
BLK (G401)
WHT (Key
interlock switch input)
BLKBLU (Park lnput)
WHT/RED (Shinlock circuit control)
WHI/BLK(Park pln switch input)
6
7
27. C352
- Gray- On bottom of under-hood {use/relay box- On main wire harness
1
789
I
1
2
3
4
GRN (Fans)
BLUAVHT (fuC
compressor controlS)
WHT/BLK(Hazard warning lights)
WHT/BLK (Fuse 42)
BLKRED (A/Ccompressor clutchrelay control)
BLK,/YEL (Fuse 17)
WHT/GRN (Fuse 52)
WHT (Fuse 48)
6
7
8
I
28. C101
- Gtay- Left rear of engine compartment- Connecls engine wire harness to main wire harness
1 l\,4ale - BLK/YELFemale - BLK,ryVHT(Fuse 15)
2 BLK (G101)
3 YEURED (Oilpressure indicator light)
4 *1/*4: BRN/BLK (G101)
5 YEUBLK (PGI\4,FD
6 WHT/BLU(Charging system)
7 YEL/GRN (Gauges)
I *1: BLU (lgnition
sYstem)
9 Male - BLK VHTFemale - BLKRED(Slarting system)
10 *2: BLKryEL(lgnition system)*3: Male - BLK/YELFemale - RED(lgnition system)
*1= 96-'98 models: All'99: D16Y5 with M,iT*2= '96-'97 models: All'98-'99 modelsr GX*3= '96-'98 models: All except GX*4=: '98''00 Models: GX
202-7

Connector ldentification and Wire Harness Routing
Connector
or
Terminal
Number ol
Cavities/
Color
LocationConnects toNotes
Main Wire Harness (Left side of dash and floor branch): '96-'97 models
c401
c402
c403
c404
c405
c406
c407
c407
c408
c409
c410
c411
c412
c413
c414
c415
c416
c417
c418
c419
c420
c421
c422
w+4J
c424
c425
c427
c428
c429
c430
c431
c432
c433
c434
lJ+OC
c437
v+.to
c439
14-GRY
4-ORN
4-NAT
14-GRY
4-NAT
8-GRY
2-GRY
2-GRY
1-BRN
1O-WHT
12-GRY
24-BLU
3-YEL
16-GRY
4.BLU
7-BRN
6.NAT
2-N/A
2-YEL
18-GRN
2O.GRN
18-GRN
7-GRN
6-GRN
4-NAT
4-WHT
8.WHT
6-WHT
4-NAT
7-NAT
3-GRY
8-GRY
4.GRY
14-GRY
2-GRY
4-GRY
26-GRY
22-GRY
1-GRN
Behind left kick panel
Behind left kick panel
Under left side ot dash
Under left side of dash
Under left side of dash
Under left side of dash
Under lett side ot dash
Under left side of dash
Under left side of dash
Behind under-dash fuse/relay box
Above under-dash fuse/relay box
Above under-dash fuse/relay box
Above under-dash fuse/relay box
Under left side of dash
Under left side of dash
Above under-dash fuse/relay box
Under left side of dash
Under left side of dash
Under left side of dash
Behind under-dash fuse/relay box
Behind under-dash fuse/relay box
Behind under-dash fuse/relay box
Front of under-dash iuse/relay box
Front of under-dash fuse/relay box
Under left side of dash
Under left side of dash
Behind steering column cover
Behind steering column cover
Behind steering column cover
Behind steering column cover
Under left side of dash
Under lett side ot dash
Below front console
Below front console
Below front console
Below front console
Behind lett kick panel
Behind left kick panel
Behind under-dash fuse/relay box
Floor wire harness
Floor wire harness
Light flasher relay connector(Security)
Cruise control unit
DRL control unit connector A
DRL control unit connector B
Roof wire harness
Moonroof wire harness
Front fog light connector
Integrated control unit
Dashboard wire harness
Dashboard wire harness
SRS main harness
Data link connector
Starter cut relay
lgnition switch
Security starter cut relay conneclor
Clutch switch
Clutch interlock switch
Under-dash fuse/relay box
Underdash fuse/relay box
Under-dash fuse/relay box
Under-dash fuse/relay box
Underdash fuse/relay box
Horn relay
Brake switch
Combination wiper switch
connector A
Combination wiper switch
connector B
Combination light swilch
connector A
Combination light switch
connector B
Cable reel
lnterlock control unit
Secondary heated oxygen sensor
sub-narness
A,/T gear position switch
Shift lock solenoid
Park pin switch and A,/T gear
position console light
TCM connector A
TCM connector B
Under-dash luse/relay box
ABS
Optional
Canada
Canada-2
'4
Optional
AtT
M/T
Optional'5
M/T
Atl
'6
AN
AN
Atf
CVT
CVT
G401Left kick panelBody ground, via main wire
harness
.2: Without moonroof .5: M/T (with cruise control or for D16Y5 engine)"4: With moonroof .6: With secondary heated oxygen sensor (HO2S)
203-20

Connector ldentification and Wire Harness Routing
Connector
or
Terminal
Number of
Cavities/
Color
LocationConnects toNotess
Main Wire Harness (Left side of dash and tloor branch): '98 model and all GX models
c401
c402
c403
c404
c405
c406
Q407
c407
c407
c408
c409
c410
c411
c412
c413
c414
c415
c416
c417
c418
c419
c420
c421
c422
c423
c424
c425
c426
c427
c428
c429
c430
c431
c432
c433
c434
c435
c437
c438
c439
c447
c448
14-GRY
4.ORN
4-NAT
14-BLU
4-NAT
8.GRY
2.GRY
2-GRY
6.GRY
1-BRN
1O-WHT
12-GRY
24-BLU
3-YEL
16-GRY
5-BLK
7-BRN
6-NAT
2.N/A
2.YEL
18.GRN
2O.GRN
18-GRN
7.GRN
6.GRN
5-BLK
4.WHT
8-WHT
6-WHT
4-NAT
7-NAT
3.GRY
8-GRY
4-GRY
14-GRY
2.GRY
4.GRY
26.GRY
22-GRY
1.GRN
4-N/A
26-GRY
Behind lett kick panel
Behind lett kick panel
Under lett side of dash
Under lett side ol dash
Under lett side of dash
Under left side of dash
Under lett side of dash
Under lett side ot dash
Under left side of dash
Under l€ft side of dash
Behind undsr-dash tuse/rBlay box
Above under-dash tuse/relay box
Above under-dash tuse/relay box
Above under-dash fuse/relay box
Under lett side of dash
Under-dash relay box
Above under-dash tuse/relay box
Under left side of dash
Under lett side of dash
Under left side of dash
Behind under-dash tuse/relay box
Behind under-dash tuse/relay box
Behind under-dash tuse/relay box
Front of under-dash tuse/relay box
Front ol under-dash fuss/relay box
Under-dash relay box
Under lett side ot dash
Behind steering column cover
Behind steering column cover
Behind steering column cover
Behind steering column cover
Und€r left side of dash
Under lett side of dash
Below front console
Below front console
Below front console
Below front console
Behind left kick panel
Behind left kick panel
Behind under-dash fuse/relay box
Under lett side of dash
Behind left kick panel
Floor wire harness
Floor wire harness
Light tlasher relay connector (Security)
Cruise control unit
DRL control unit connector A
DRL control unit connector B
Boot wire harnsss
Moonroof wire harness
Boof wire harness
Front fog light connector
Integrated control unit
Dashboard wire harness
Dashboard wire harness
SRS main harness
Data link connector
Starler cut rslay
lgnition switch
Security strarter cut relay connector
Clutch switch
Clutch interlock switch
Under-dash fuse/relay box
Under-dash fuse/relay box
Under-dash fuso/rolay box
UndeFdash fuse/relay box
Under-dash fuse/relay box
Horn relay
Brake switch
Combination wiper switch connector A
Combinalion wiper srvitch connector B
Combinalion light switch connector A
Combinalion lighi swilch connector B
Cable reel
lnterlock control unil
Secondary heated oxygen sensorsuD-narness
A,/T gear position switch
Shift lock solenoid
Park pin switch and A/T gearposition console light
TCM connector A
TCM connector B
Underdash lus€/relay box
Fuel injector relay
Injector control module
ABS
Optional
Canada
Canada,2
,4
'7
Optional
AIf
Mtf
Oplional'5
M/T
AN'6
An
A,/T
Alf
CW
CVT'7
'7
'7
G401Left kick panelBody ground, via main wire harness
-2: Without moonroof (except GX)-4: With moonroof'5: M/T (with cruise control or for D16Y5 engine)'6: With secondary heated oxygen sensor (H02S)t7: GX model
203-22

Connector ldentification and Wire Harness Routing
Connector
ol
Terminal
Number ot
Cavlties/
Color
LocationConnects toNotes\
Main Wire Harness (Left side of dash and floor branch): '9$00 models except GX model
c401
c402
c403
c404
c405
c406
c407
c407
c408
c409
c4t0
Q411
c412
c413
c414
c415
c416
c417
c418
c419
c420
c42'l
c423
c424
c425
c426
c42A
c429
c430
c431
c432
c433
c434
c435
c447
c448
c450
c451
2O.GRY
4.ORN
4.NAT
14.BLU
4-NAT
8-GRY
6.GRY
6.GRY
1-BRN
1o-wHT
12-GRY
24-BLU
3.YEL
16-GRY
5.BLK
7-BRN
6.NAT
2-N/A
2-YEL
18.GRN
2O.GRN
18.GRN
7.GRN
6.GRN
5-BLK
4.WHT
8.WHT
6-WHT
4-NAT
7.NAT
3.GRY
8.GRY
4-GRY
14-GRY
2-GFY
4-GRY
22.GRN
2-GRY
3-GRY
18-GRY
Behind left kick panel
Behind left kick panel
Under left side of dash
Under lett side oI dash
Under lett side of dash
Under letl side ol dash
Under lett side oI dash
Under letl side oI dash
Under lefl sids ol dash
Behind under-dash fuse/relay box
Above under-dash fuse/relay box
Above under-dash fuse/relay box
Above under-dash fuse/relay box
Under lett side ot dash
Under-dash relay box
Above under-dash fuse/relay box
Under left side of dash
Under left side ot dash
Under lett side of dash
Behind under-dash fuse/relay box
Behind under-dash fuss/relay box
Behind under-dash fuse/relay box
Front of under-dash fuse/relay box
Front of under-dash fuse/relay box
Under-dash relay box
Under loft side ot dash
Bohind steering column cov6r
B6hind stesring column cover
Behind steering column cover
Behind steering column cover
Under lett side ot dash
Under lett side ot dash
Below fronl console
Below front console
Below front console
Below front console
Under lett side ot dash
Under lett side of dash
Under left side of dash
Behind lett kick panel
Floor wire harness
Floor wire harness
Light flasher relay connector (Sscurity)
Cruise control unil
DRL control unit connector A
DRL control unit conn€ctor B
Roof wire harness
Moonroof wire harnsss
Front tog light connector
Intsgratgd control unit
Dashboard wire harn€ss
Dashboard wire harness
SRS main harness
Data link connector
Starter cut relay
lgnition switch
S€curity starter cut relay connector
Clutch switch
Clulch interlock switch
Under-dash fuse/relay box
Under-dash tuse/ralay box
Under-dash tuse/ralay box
Under-dash fuse/relay box
Under-dash fuse/relay box
Horn relay
Brake switch
Combination wiper switch connector A
Combination wiper switch conn€ctor B
Combination light switch connector A
Combination light switch conn€ctor B
Cable reel
lnterlock control unit
Secondary heated oxygen sensorsub-narnsss
A/T gsar position switch
Shitt lock solenoid
Park pin switch and A/T gearposition consolo light
Security control unit connactor
Security LED connector
Valet switch connector (Security)
Keyless door lock control unit
ABS
Optional
Canada
Canada
Optional
AN
Mrl
Optional'5
M/T
AN'6
An
Atf
Atf
Optional
Optional
Optional
MKoyloss
G401Left kick panelBody ground, via main wirenarness
'2: Without moonroof"4: With moonroof'5: M/T (with cruise control or for D16Y5 engine)'6: With secondary heated oxygen sensor (HO2S)
203-24