1997 HONDA CIVIC Ground

ldle Control System
Air Conditioning Signal ('99 - 00 Models except Dl6Y5 engine with M/Tl
This signals the ECM/PCM when there is a demand for cooling from the air conditioning system.
ECM/PCM CONNECTORS
a l32P)
ECM/PCM CONNECTOR A {32P)
Wire side of female terminals
ECM/PCM CONNECTORS
A (32P1
Chock tor a short in ihe wi.e(ACS lin6):1. Turn the ignition switch OFF.2. Disconnect the A/C pressure
switch 2P connector.3. Turn the ignition switch ON (ll).
4. Measure vo ltage betweenECM/PCM connector terminals A27 and 820.
Check for a short in the wire (ACS
linel:'1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM connector A (32P).
3. Check lor continuity betweenbody ground and ECM/PCMconnector terminal A27.
Reoair short in lhe wi.e botweonthe ECM/PCM (A271 and rhe A/Cpressure swilch.
Srr66tituto a known{ood ECM/PCt4 tnd rechock. It prascrib€dvoltage is now available, re-plac€ the original ECM/rcM.Soo the air conditioner insoec-tion {see s€ction 22}.
Check to. an opon in tho wi.e(ACC linel:1. Turn the ignition switch OFF.2. Reconnect the A/C pressure
switch 2P conneclor.3. Turn the ignition switch ON (ll).
4. Momentarily connect ECN4/PCM connector terminals A17and 820 with a jumper wire
(To page '! 1-207)
11-206
LGl {BRN/BLK)

I
JUMP€RWIRE
UNDER-HOOO FUSE/RELAYsox 9P coNNEcroR lca52l
123a
5689
ACC (8LK/REDI
Wire side ofterminals
ECM/PCM CONNECTORS
A (32P1
female
Wire side of {emale terminals
(From page 11-206)
Check for an open in the wite
IACC lino):Momentarily connect under_hood
luse/relay box 9P connector teF
minal No. 5 to body ground with
a jumper wire several times.
ls there a clicking noise from
the Iy'C compressor clutch?
S6e air conditioner insPoction
l3oa section 221ls there a clicking noise lrom
the ly'C compressor clutch?
Ropair open in tho wilo betwg€n
the ECM/PCM lA17) and the A/C
clutch rolay.
Chock for the oporation of lho
AIC:1, Start the engine.
2. Turn the blower switch ON
3. Turn the ray'C switch ON.
Check lor an open in the wiro(ACS lino):Measure voltage between ECM/
PCM connector terminals A27
and 820.
Does the Iy'C operate?
Air conditioning signal is OK.Repair op6n in the wiro bctwoon
lhe ECM/PCM lA27l and tho A/C
3witch.ls voltage lessthan 1.0 V?
- Sub6iitut€ r known€ood ECtt /PCM and rccheck. ll sYmP-
tom/indication 9oe3.waY,replaca the original ECM/PCM- See the ai. condhionGr in3p€c-tion lsee soc{ion 221.
11-207

ldle Control System
Alternator (ALTI FR Signal {'96 - 98 Models,'99 - 00 Dl6y5 engine with M/Tl
ECM/PCM CONNECTORS
a {32P)
LGl(BRN/BLK)
Wire side of female terminals
ALT CONNECTORS IC1O4I
JUMPER
JUMPER WIRE
WIRE
Wire side of female terminals
ALT F{WHT/REO)
This signals the ECM/PCM when the Alternator (ALT) is charging.
Inspoction of ALT FR Signal.
Check tor a short in tfte wire (ALTF linel:1. oisconnect the 4P (3P)* con-nector from the ALT.2. Turn the ignition switch ON (ll).3. M easu re voltage betweenECM/PCM connector terminals C17 and A9.Check lor a sho.t in the wire {ALTF line):r. I urn rne tgn|lton swtlch ul-f,2. Disconnect the negative bat-tery cable from the baftery.3. Disconnect the ECM/PCM connector C {31P).4. Check for continuity betweenbody ground and ECM/PCMconnector terminal C17.
ls there approx. 5 V?
Check th€ operation of the ALT:1. Turn the ignition switch OFF.2. Reconnect the ALT 4P (3P)*connector to the ALT.3. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untjlthe radiator fan comes on, thenlet it idle.4. [,4easu re voltage betweenECM/PCM connector terminalsC17 and A9.
Repair short in the wire betwe€nthe ECM/PCM {Cl71and th€ ALT.
Substitute a known-good ECM/PCM and recheck. It prescribedvoltage is now available, roplacethe originrl ECM/PCM.
Does the voltage decrease whenheadlights and rear defogger areturned on?ALT FR signal is OK.
Check tor an open in the wire (AlTF linel:1. Turn the ignition switch OFF.2. Disconnect the negative bat-tery cable from the battery.3. Disco n nect the ECM/PCMconnector C (31P).4. Disconnect the 4P (3P)* con,nector from the ALT.5. Connect the ALT 4P 13P)l connector terminal No. 4 (No. 1)'to body ground with a iumper
6. Check lor continuity betweenbody ground and ECM/PCMconnector terminal C17,
Repair op6n wire botween th€ECM/PCM (C171rnd th€ ALT.ls there continuity?
c {31P)
1178I10
1112131415161718
232125a30
oALT F IWHT/REDI
4P3P*
1 2l
Flr
rr-ri-frwHr/ (V)
neor Y
*: Canada model
11-208
3I78910
1l1213l415161718/l
232125E30
oALT F IWHT/REDI

tAlternator (ALT) FR Signal ('99 - 00 Models except Dl6Y5 engine with M/T)
This signals the ECM/PCM when the Alternator {ALT) is chargingECM/PCM CONNECTORS
Wire side of female terminals
ECM/PCM CONNECTOR C (31P}
lt
lP
ALT CONNECTORS IClO4I
JUMPER
JUMpER WlnE
WIRE
Wire side of female termlnals
ECM/PCM CONNECTOR C (31PI
3P*NO
Check lor an op€n in the wire (ALT
F line,:1. Turn the agnition switch OFF
2. Disconnect the negative bat-
tery cable {rom the battery.
3. Disconnect the ECM/PCM con'
nector C (31P).
4. Disconnect the 4P (3P)* con'
nector from the ALT.
5. Connect the ALT 4P (3P)* con-
nector terminal No 4 (No. 1)*
to bodY ground with a iumper
6. Check lor continuity between
body ground and ECM/PCM
connector terminal C5
--?--1l2l|#i3l.l
otriJrwxrr (V)
neor Y
lnsoeclion oI ALT FB Signal.
Check {or a short in the wire {ALT
F line):1. Disconnect the 4P (3P)+ con
nector from the ALT
2. Turn the ignition switch ON (ll)
3. Measurc voltage between EcM/
PCM connector terminals C5
and 820.Check tor a short in the wirc (ALt
F line):1. Turn the ignition switch OFF
2. Disconnect the negative bat_
tery cable from the baRery'
3. Disconnect the ECM/PCM con'
nector C (31P).
4. Check for continuity between
body ground and ECM/PCM
connector terminal C5
ls there aPProx. 5 V?
Check the operation otthe ALT:
1. Turn the ignition switch OFF.
2- Reconnect the ALT 4P (3P)*
connector to the ALT
3. Start the engine. Hold the
engine at 3,000 rpm wrth no
load {in Park or neutrali until
the radiator fan comes on,
then let it idle.
4- Measure voltage between ECM/
PCM connector terminals C5
and 820.
Repair short in the wire between
the EcM/PCM {C5l and the ALT.
Substitute a known-good ECM/
PCM and rechock. lf P.esc.ibedvoltage is now availabl€, ieplace
tho original ECM/PCM
Does the voltage decrease when
headlights and rear delogger are
turned on?
ALT FF signal is OK.
Repair oPen wire betwoen t|lo
ECM,/PCM {C5) and the ALT.
ALT F (WHT/RED)
Wire side of temale terminals
*: Canada model
Wire side of female termrnals

t
(From page 11 212)
Check lor a 3hort in the PSP
switch:1. Turn the ignition switch OFF.
2. Disconnect the 2P connector
from the PSP switch.
3. Turn the ignition switch ON (ll)
4. Measure voltage between
ECM/PCM connector termi-
nals Ag and C16.
Check tor a short in the wiro {PSP
SW linel:'1. Turn the ignition switch OFF.
2. Disconnect the ECM/PCM con
nector C (31P).
3. Check lor continuity between
body ground and ECM/PCM
connector terminal C16.
ls there battery vohage?
Repair ahort in the wire between
the ECM/PCM (C16) and th6 PsP
switch.
Substitute a known_good ECM/
PCM end rechock. lf Prescribedvoltage b now avsilable. rePlace
the original ECM/PCM.
ECM/PCM CONNECTORS
Wire side of temale terminals
'l
12a6189t0
tl12131415161718
232125a30
oPSP SW (GRNI
1-213

\
(From page 11'2141
Check lor a short in tho PSP
swhch:1. Turn the ignition switch OFF
2. Disconnect the 2P connector
from the PSP switch
3. Turn the ignition switch ON {ll)
4. Measure vohage between ECW
PCM connector terminals A26
and 820.
Ch6ck for a short in tho wiro IPSP
SW lino,:1. Turn the ignition switch OFF
2. Disconnect the ECM/PCM con-
nector A (32P).
3. Check for continuity betweon
body ground and ECM/PCM
connector terminal A26
Rogair short in the wiro b€{woon
the ECM/PCM (A26) and the PSP
switch.
Substitute a known_good ECM/
PCM rnd r.check. lf Prdcribodvohago is now avaihblo' rcPl.co
the original ECM/PCM
ECM/PCM CONNECTORS
ECM/PCM CONNECTOR A I32P)
Wire side of lemale terminals
Wire side of female terminals
'l'
5-21

ldle Control System
Automatic Transaxle (CVTI Gear Position Signal
('96 -98 D16Y5 engine with CW)
ATP NP{LT GRNI
INP
GBN)
This signals the ECM when the transmission is in @ or @ position.
Check the operation oI the A/Tgear position switch:1. Turn the ignition switch ON flt).2. Observe the A/T shift positionindicator and select each position separately.
See lhe A/T gear position indica-tor insp€ction {see sec{ion l/tl.
Check tor a short in the wir6 (ATpNP line):1. Turn the ignition switch OFF.2. Disconnect the 14P connectorIrom the gauge assembly.3. Disconnect the 26P connectorfrom the TCM.4. Turn the ignition switch ON fll).5. Measure voltage between ECMconnector terminals A9 andc29.
Check for a short in the wire lATpNP linell1. Turn the ignition switch OFF.2. Disconnect the ECM connector C (31P).
3. Check for continuity betweenbody ground and ECM connector terminal C29.
ls there approx. 5 V?
Check for an open in the wire lATpNP lina):1. Turn the ignition switch OFF_2. Beconnect the 14P connectorto the gauge assembly.3. Reconnect the 26P connectorto the TCM.4. Sta rt the engine.5. Measure voltage betweenECM connector terminals A9and C29 with the transmission in E and E posationt
Repair short in the wire betweenthe ECM {C291 and the gaugeassemblv,
Substitute a known-good ECMand recheck. lf prescribed volt-age is now avrilable, replace theo.iginalECM.
Wire side ot female terminals
2457I910
t112131a15151718
2321252930
ATP(LT io
(To page 11'217)
11-216

ldle Control System
{
(
a
Clutch Switch Signal (Dl6YS engine with M/Tl
This signals the ECM when the clutch is engaged.
A {32P}
ECM CONNECTORS
LGl (BRN/BLK)
\-
cLsw(RED}
Inrpaction ot dutch rwitch signal.
Check for on opon in the wiro(CLSW linel:'!. Turn the ignition switch ON (ll).2. Measure voltage betweon ECt!4connector terminals C29 andA9.
Ch.ck tho clutch switch:1. Turn the ignition switch OFF.2. Disconnect the 2P connectorfrom the clutch switch.3. Turn the ignition switch ON (ll).4. Measure voltage b€tween ECMconnector terminals C29 and
ls thare approx. 5 V?
ls there approx. 5 V?
Check for a short in th6 wire(CLSW line)l1. Turn the ignition swirch OFF.2. Disconnect the ECM connector C (31P)trom the ECM.3. Check lor continuity betweenECM connector terminal C29and body ground.
Chcck for an open in thg wire{CLSW linel:1. Depress the clutch pedal.2. Moasure voltage between ECMconnector torminals C29 andA9.
Repair short in the wirc betweentho ECM {C291 and tho clurchswitch.
Sub3titutg a known-good ECMand rechock, It p.e3cribed vohagoi! now available, roplace the orig-inal ECM.
Wire side of female terminals
26189101l12t3'tat5l617l822
o
(To page 11-219)
11-218
!