Page 448 of 2189

Electrical Load Detector (ELDI {'96 - 98 Models,'tn - 00 D16Y5 engine with M/T}
The scan tool indicates Diagnostic Trouble code (DTC) P1297: A low voltage problem in the Electrical Load
Detector (ELD) circuit.
ELD 3P CONNECTOR (c35'rl
l-- ,ll l2l3l--f ..
ao (GRN/REDI
Y
ECM/PCM CONNECTOR O I16PI
Wire side of female terminals
Problem verification:'!. Do the ECM/PCM Reset Pro-
cedure.2. Sta rt the engine
3. Turn on headlightslntermittent tailure, sYstem is OK
at this time. Check for Poor con-
nection3 or loose wires at C131
tlocated under righl side of da3h).
C354 (ELDIand ECM/PCM.
ls DTC P1297 indicated?
Ch.ck lor short in the ELD:
Measure voltage between body
ground and the ELD 3P connector
terminal No.3.
ls there approx.4 5 V?
Check for a short in tho wile (EL
linel:1. Turn the ignition switch OFF'
2. Disconnect the ECM/PCM con
nector D (16P)
3. Check for continuity between
body ground and ECM/PCM
connector terminal D16
R6pair short in the wire between
ECM/PCM (D161and ELD.
Substitute a known-good ECM/
PCM and recheck lf symplom/
indication goes awaY, rePlace
the original ECM/PCM
ra
11-179
Page 449 of 2189

PGM-Fl System
Elestrical Load Detector |ELD) t'glf - 00 Models except D16y5 engine with M/Tl
The scan tool indicates Diagnostic Trouble Code (DTC) P'1297; A low voltage probtem in the Electrical LoadDetector (ELD) circuit.
ELD 3P CONNECTOR tC354)
EL{GRN/REOI
ECM/PCM CONNECTOB A I32PI
Wire side of lemale terminals
Problem verilication:1. Do the ECM/PCM Reset Pro-cedure.2. Sta rt the engine.3. Turn on headlights.
Inlermittont failur6. systom i3 OKat this time, Chock tor ooor con-nestions or loose wires at C131(locrted undor ight side ot d.shl,C354 (ELDI and ECM/PCM.
Check for short in th6 ELD:Measure voltage between bodyground and the ELD 3P connectorterminal No.3.
ls there approx. 4.5 V?
Check to. a short in the wne (ELlinel:'L Turn the ignition switch OFF.2. Disconnect the ECM/PCM con-nector A (32P).
3. Check tor continuity betlveenbody ground and ECM/PCMconnector terminal A30.
Repair short in the wile betweenECM/PCM lA30) and ELD.ls there continuity?
Sub3titute a known-good ECM/PCM and rech€ck. It symptom/indication goes away. replacethe o.iginal ECM/PCM.
1 1-180
Page 451 of 2189

PGM-FI System
Elestrical Load Detector (ELDI ('99 - 00 Models except D16y5 engine with M/Tl
The scan tool indicates Diagnostic Trouble code (DTCI Pl298: A high vottage problem in the Etectrical LoadDetector (ELD) circuit.
ELD 3P CONNECTOR (65/0
EL {GRN/REOI
Wire side of fernale terminals
ELD 3P CONNECTOR (CA54I
TIr l2l3l
I crvo
(o) (BrKr
Y
Wire side of lemale terminals
ECM/PCM CONNECTORSA (32P1
Wire side of lemaleEI- IGRN/RED)terminals
ECM/PCM CONNECTORS
A {32P)
Problem ve.itication:1. Do the ECN4/PCM Reset pro
cedure.2. Start the engine.3- Turn on headiights.Inte.mittent teilu.e, svstem is OKat this lime. Chock for Door con-nections or loose wires at Ci31{located under Jight side otdaihl, C354 (ELD) and ECM/PCM.
ls DTC P1298 indicated?
Check for an open in the wire{lG1 line}:1. Turn the ignition and head-lights OFF.2. Disconnect the ELD 3P con
3. Turn the ignition switch ON (ll).4. Measure voltage between bodyground and the ELD 3P connec-torterminalNo. 1.
Repair opon in tho wiro batwe€nNo. 15 ALTERNATOR Sp SENSOR{7.5 A} fuse in th6 undor-dashIuse/reley box and ELD.
ls there battery voltage?
Check for an open in the wiro{GND linel:1. Turn the ignition switch andheadlights OFF.2. Disconnect the ELD 3P connector.3. Check for continuity betweenbody ground and the ELD 3Pconnector terminal No. 2,
Repair open in the wire bstwoenELD connsctor and Gia02.
Check ,or an open in the wire IELlinel:1. Disconnect the ECM/PCM con-nector A (32P).2. Check for continuity betweenthe ELD 3P connector terminalNo. 3 and ECM/PCM connec-tor terminal A30.
Chock fo. a malfunction in the ELD:'1. Reconnect the ELD connectorand ECM/PCM connectorA (32P).
2. Stan the engine and allow itto idle.3. While measuring voltagebetween ECM/PCM connectorterminals A30 and B2O, turnthe headlighrs on ow).
ls there continuity?
Repsir op€n in the wire betweenELD connector and ECM/PCM.
Substitute a known-good ECM/PCM and recheck. lf symptom/indication goes away. replacelh6 original ECM/PCM.
Does the vokage drop?
Wire side of f€male terminals
11-182
Page 453 of 2189
PGM-FI System
(From page 11 183)
Check lor an open in the wiresICKF lines):1. Reconnect the CKF sensor 3p
2. Dlsconnect the ECM/PCM con-nector C (31P).3, Measure resistance betweenECM/PCM connector terminals Cl and Cl1.
Repair open in the wire betweenECM/PCM {C1, C11} and the CKFls there 1.6 3.2 kO?
Check for a short in the wire{CKF line}:Check for continuity betweenbody ground and ECM/PCM con,nector terminal C1.
Repair short in the wiro bstwoenECM/PCM {Cl) and the CKF son-
Substitute a known-good ECM/PCM, and recheck. lf symptom/indication goes awry, replace theoriginal ECM/PCM.
Crankshaft Speed Fluctuation (GKFI Sensor('96 - 98 Models,'99 - 00 D16V5 engine with M/Tl (cont,d)a\
ECM/PCM CONN€CTOR C (31P}
CKF P(8LU/REO)
CKF M(WHT/REO)Wire side of femaletermtnats
CKF P(BLU/RED)
6r l-i
rF
tl
a678910
12131115t61718
21272A2930
11-184
Page 455 of 2189
PGM-FI System
Crankshaft Speed Fluctuation (GKFI Sensor('99 - 00 Models except D16YS engine with M/Tl (cont,d)I\
ECM/PCM CONNECTOR C 13lPI
Wire side of femaleterminals
aI
(Frorn page l1-185)
Check Ior an opsn in the wires(CKF lines):1. Reconnect the CKF sensor 3pconnector.2. Disconnect the ECM/PCM con-nector C {31P}.3. Measure resistance betw€enECM/PCM connector termi-nals C22 and C31.
Repair opqn in th. wire bo{weenECM/PCM (CZ, Ctll and th. CKFlon30r.
ls there 1.6-3.2 k0?
Check tor a short in the wireICKF line):Check for contin!ity betweenbody ground and ECM/PCM con-nector terminal C22.
Roplir thort in tho wirg b.iwoonECM/FC'ftl lc22l and tho CKF 3€n-
Substituto a known-good ECM/PCM, and r.ch.ck. It symptom/indication 90o. aw!y, 6pbco theoriginal ECM/PCM.
1 1-186
Page 458 of 2189

[F16551l Th" ""un toot indicates Diagnostic Trouble Code (DTC) P1681: TIVA,/TMB signal line failure
Problem verification:1. Do the ECM Reset Procedure.
2. Drive the vehicle Ior several
miles at varying speeds
lnt.rmittent failure, system is OK
at ihis time. Check tor Poor con-
nections or loos€ wires at C131
llocated under right side of dash),
C438 ITCM) and ECM.
ls DTC P1655 indicated?
Check lor an oPen in the wire(TMA line):1. Turn the ignition switch OFF
2. Disconnect ECM connector C(31P)from the ECM
3. Turn the ignition switch ON (ll).
4- Measure vo ltag e between
ECM connector terminal Cg
and body ground.
Check for a short in the wire
ITMA line,:Measure voltage between TCM
22P connector terminal No 7 and
body ground.ls there battery vohage?
Ropair shod in the wire bstwe€n
the EcM (C!l) and the TcM.ls there battery voltage?
Check for an open in the wire
{TMB line}:1. Turn the ignition switch OFF
2. Reconnect ECM connector c(31P).
3. Disconnect the 22P connector
from TCM.4. Turn the ignition switch ON (ll).
5. Measure vo ltage between
TCM 22P connector termlnal
No. 6 and body ground.
Repair open in the wire between
th€ EcM {Ca) and the TcM.
Check for a 3ho.t in the wire
{TMB lin6,:Measure voltage between ECM
connector terminal C30 and bodyground,
ls there battery voltage?
Substitute a known'good ECM
and recheck. It symPtom/indica'tion goes away, teplace the origi-
nal ECM.
Reoair short in the wile b6tween
the ECM {C30} and the TCM.ls there baftery voltage?
f,epair open in the wire between
the EcM (C30) and the TcM.
IJA/T Signal (TMA/TMBI ('96 - 98 Dl6Y5 engine with GW)
ECM CONNECTOR C 131P}TMA IGRYI
fcu22PCONNECTOR
ll
TMB*{PNK}
231678910
1t'12131415161718
232a252930
Wire side oI temale
terminals
tl,
1 1-189
Page 463 of 2189

ldle Control System
ldle Air Control (lACl Vatve ('96 - 98 Dl6ys, Dl6yB engine with M/Tl
The scan tool indicates Diagnostic Trouble Code (DTC) P1508: A problem in the ldle Air Controt flAC) varvecircuit.
The IAC Valve changes the amount of air bypassing the throttle body in response to a current signal from the ECM inorder to maintain the proper idle speed.
IAC VALVE 2P CONNECTOR ICl3A)
,flrcerh-:J iYEL/BLKI
!.__-,/ -lt(v)
-T-=
Wire side of female terminals
tAcv(BLK/
ELUI
ECM CONNECTOR A I32PI
Wire side oI lemal€ terminals
VALVE
6a10ll12t3r5t6l7t8t920232a
t*25&a2A3o
The MIL hss b€on repo.ted on.DTC P'l508 i. itorod.
Problem vorification:1. Do the ECM/PCM Reset Pro-cedure,Start the engine, and warm ituP to normal operating tem-perature.
Intormittont t!llur., sy.tcm b OKat thb tim6. Chsck fol poor con-ncctionr or loo3e wirot at C138(lAC valv.l.nd ECM.
ls DTC P1508 indicated?
Check for an opcn in the wiro(lGPl line):1. Turn the ignition switch OFF.2. Disconnect the IAC valve 2Pconnector.3. Turn the ignition switch ON (ll).
4. Measure vohage between bodyground and the IAC valve 2Pconnectorterminal No. 2.
R.prir opan in the wiro botwa.nIAC valv..nd PGM-FI main r.l.y.
Chock for an opon or sho in thewire (IACV linal:1. Turn the ignition switch OFFand reconnect the IAC valveconnector.2. Disconnect the ECM connectorA (32P).
3. Turn the ignit;on switch ON (ll).4. Measure voltage betweenbody ground and ECM con-nector terminal A12.
(To page 1l-195)
11-194
Page 465 of 2189
![HONDA CIVIC 1999 6.G Workshop Manual ldle Gontrol System
ldle Air Control (lAG) Valve (99 - 00 Dl6Y8 engine with M/T, Bt6A2 enginel
[Fl50g l ]h" scan tool indicates Diagnostic Trouble Code (DTC) P1508: A problem in the ldle Air Controt HONDA CIVIC 1999 6.G Workshop Manual ldle Gontrol System
ldle Air Control (lAG) Valve (99 - 00 Dl6Y8 engine with M/T, Bt6A2 enginel
[Fl50g l ]h" scan tool indicates Diagnostic Trouble Code (DTC) P1508: A problem in the ldle Air Controt](/manual-img/13/6068/w960_6068-464.png)
ldle Gontrol System
ldle Air Control (lAG) Valve ('99 - 00 Dl6Y8 engine with M/T, Bt6A2 enginel
[Fl50g l ]h" scan tool indicates Diagnostic Trouble Code (DTC) P1508: A problem in the ldle Air Controt AC) vatve- CtrCUtt.
The IAC Valve changes the amount of air bypassing the throttle body in response to a current signal from the ECM inorder to maintain the proper idle speed.
IAC VALVE 2P CONNECTOR IC138'
la rcprI - {YEL/8LKI 2t--d,
Y-=
Wire side ot female terminals
Wire side of lemale terminals
VALVE
The MIL has boon r€oorted on.DTC P1508 is srored.
Probl6m verification:1. Do the ECM/PCM Reset Pro-cedure.2. Start the engine, and warm itup to normal operating lem-perature.
Intermittent tailure, system is OKat this timg. Check to. poor con-noctions or loose wires at C138{lAC valvel and ECM.
ls DTC P1508 indicated?
Ch6ck for an open in the wir€{lGPl lino}:1. Turn the ignition switch OFF.2. Disconnect the IAC valve 2Pconnector.3. Turn the ignition switch ON (ll).
4. Measure voltage between bodyground and the IAC valve 2Pconneclor termina I No.2,
Repair opon in the wire bgtwoenIAC valve and PGM-Fl main relay.
Check tof an open or short in thewire {IACV line}l1. Turn the ignition switch OFFand reconnect the IAC valve
2. Disconnect the ECM connectorB {25P).3. Turn the ignition switch ON (ll).
4. Measure voltage betweenbody ground and ECM conn€ctor terminal 823.
(To page 11-197)
1 1-1 96