Ecm HONDA INTEGRA 1994 4.G Service Manual

Disconnect the "B" connectorfrom the ECM only, not the mainwile hatness.
Turn the ignition switch ON.
Block tho right front who€l andslowlv rotate l6ft front wheel andm€asure voltage between 8'l Ol+) terminal and A26 (-)
terminal.- Roo.ir lhort in ORt{wire belween ECM18101 tnd rhs VSSor cruia6 controlunit.- ncp.i. op€n in ORI{wira botwoan ECM(8101 and the vSS.- It wir. i! OK, totttho vSS. lsoc aec-tion 231
Doos voltage pulso O V and'to v?
SubrtituL . known-good ECil lndEch.ck. fi lynptom/ndcltbn gp..
rw!y, .rpleco lh. original ECM.
(From page 1 1-68)
1 1-69

PGM-FI System
Electrical Load Detector (ELDI
tft;-]/ The Maltunction Indicaror Lamp (MlL) indicatss Diagnostic Trouble Code IDTC) 20: A probtem in-Li!- tne Electrical Load Detecror {ELD} circuit.
With lho SCS lhon connectolconnoctod {ree pago 11-34}, cod.20 is indicatod.
Do the ECM B6set Procedurs {seepage 1 'l-35).
Start engine and keep engin€speed at idle.Turn on headlights.
lntennlna tlllure, lyrtom lt Ol(!t irl. dm. (lgtt driv. mly [email protected] for Door connactlona oaloota wiro. rt C218 IELD, lndEctrt.
Ooes the MIL indicato code 20?
Romove the undgr-hood fusg/relay box and remove the tus6/relav box lowet cover.
Turn lhe ignition switch ON.
Measure voltage betw€on BLK/YEL (+l terminal and BLK (-)terminal.
Msasuro voltag€ b€tweon BLK/Y€L {+) terminal snd bodvground.ls there bartory voltagel
Rcpir oo.n in BLK wir.batwaan lha 3P connrc-tor lnd G2Ol {loc.t.dtroit ot angh|. comprn-m.r dghl .ld.l,
B.p.lr op.n in BLKrYEL wlrr b.-tw..n o.24ACG (ALn flcl115A: Bl88l .ngln!, 20 A:818C1cnginol fu!. In thr und.r{..htu.o/r.lly bor lnd tho 3P con-rcclo?.
View tromwire side
BLK (-)
(To page 11-7'l)
GRn/iED I - |
BLK/YEL I + I
11-70

(From pog6 1 1-7Ol
Meaauro voltage betweon GBN/RED ierminal and body ground.
Boplir opon 01lhort in GR /REDwir. batworn ECM (DlOl and tho
3P connoctor.1l wir. i! OK, .ubrtituta. known-good ECM .nd rochock.
13 the.e approx, 5 V?
Turn tho ignition switch OFF.
connect tho loat hamasa botweontho ECM and connectors (soa
pag€ 11-37),
wire side
BLK {_I
GR /NED I-I
BLKIEL { + }
(To page 11-72)
11-71

PGM-FI System
11-72
While measuring voltage betweenDlO 1+) terminal and 426 l-)terminal, turn the headlighr switchto the second position (a) {low).
Does the voltage drop whenthe headlights are turned on?
Subrtitute . known-good ECMand rochock. lt 3ymptom/indic€-tion goos away, ioplaco th6 origi-nal ECM.
Electrical Load Detector (ELD) (cont'd)
425 t-t D10 l+), Doos Volrago Orop? ----------------J

PGM-FI System
Knock Sensor (KS) tB18C1 enginel
ml- nl: The Malfunction Indicator Lamp (MlL) indicates Diagnostic Troubte Code (DTC) 23: A probtem inthe Knock Sensor (KS) circuit.
a6l--fzt.i--1/.---r+\
ware sido
o ooooo ooo ooo o looooooooo oooo ooo oo ooo I oooo oooo
11-74
- The MIL h6s boon r6port6don.- With th6 SCS ahort connec-tor connoctod (soe pago11-341, codo 23 is in-dicrtod.
Oo the ECM Reset Proceduro (seepage 11-35).
Start the engine. Hold the engineg!-3,Opq rpm with no load {A/T in
Lryl orlPlposirion, M/T in neurra until the radiator fan comes on,then let it idle.
Hold the engine at 3,0O0-4,000rpm for 10 seconds.Intomittor failure, ay5-t.m is OK at this tim6(teat drivo mav bonec€saary,.Chock tor Door connec-tion3 or loo3o wlaos etC222 {locatod 6r ghrshock tow6r), Cl33(KSl and ECM.Turn the ignition swirch OFF.
Connect the test harness to themain wire harness only, not to theECM (see page 1 1-37).
Check for continuity between D3terminal and body ground.
Ropdr short in RED/BLUwiro b€tweon ECM {D3land ths Ks.
(To page 11-75)

(From page 1 1-74)
Chock tor continuitv on REO/8LUwirs botween D3 tormin6l 8nd 2Pconn6ctor.
Rop.ir op.n in RED/BLU wir. b.-
twcen ECM (D3l and th. KS.
Stsrt the engine. Hold th€ engine
st 3,000 rDm with no load (A/T in
@ or@ position, (lvt/t in neutratl
until the r6diator l6n comoa on,then l6t it idl€.
Hold the engin€ at 3,000-4,OOorDm lor 10 seconds.
Subrtitutr r known{ood ECM
.nd 6ch.ck. lt tymptoh/indic!-liarn goar away. raplaca lha otigi-nd ECM.KS32 N.m (3.2
wire side
11-75

PGM-FI System
A/T Fl Signal A/B (A/T only)
\[l0l- The Maltunction Indicaror Lamp (MlL) indicates Diagnostic Trouble Code (DTC) 30: A problem In-L= the A/T Fl Signat A circuit between Transmission Control Module (TCMI and ECM.
tItil- The Malfuncrion Indicaror Lamp {MlL) indicates Diagnostic Trouble Code {DTCI 31: A problem In-Li!- the A/T Fl Signal B circuit between Transmission Controt Module (TCM) and ECM.
\.__r_/ \.__r_/-l 30 l- o'-l 3t l------ /----\
84'
+ulty? Continuity?
r: code 31 1A/T Fl signal Bl
11-76
Wlth tho SCS ahon connocrolconi|ocd {!o. p.g. 'l 1 -341, codo3O and/or 31 ars indicltod.
Oo ths ECM Resot Proceduro {seepag€ 'l 1-35).
Test drive necessary.Drive the car lor several miles sothat the transmission uDshifts anddownshilts several times.
Intormittant tsilu.o, sy3tem iB OKat thir tima,Chack lor poor connactions otl.ro!€ wiror at C419 (TCM] andECM.
Does the MIL indicare code30 and/or 31?
Turn the ignition switch OFF.
Connect the test harness to th€main harness only, not to the ECM(see p8go l'l-37).
Disconnect the 22P connectorfrom the TCM.
Check lor continuity between B3andlor 84' terminal and bodygrouno.
Ropair lhon in GRN/8LU or GRY'wiro b6twoon ECM (83 or 84'land tho TCM.
(To page 11-77)

(From page 1 'l-76)
Check for continuity on GRN/BLUor GRY'wire between 83 or 84'and 22P connector of the TCM.
Ropair open in GRN/BLU or GRY'wiro botwoon ECM lB3 or B4'land the TCM,
Substituts a known-good ECMand rochock. ll symptom/indica-tion goos 6way, roplaca tho origi-nal ECM.
11-77

System Description
The idle speed ot lhe engine is controlled by the ldle Air Control {lAC) Valve.
The valve changes the amount ot air bypassing into the intake manifold in response to electric current controlled by the
ECM. When the IAC Valve is activated, the valve opens to maintain the proper idle speed.
#l' ----rTo FGM-FIMAINRELAY
VARIOUSSENSORS
IAC VALVE
FASTIDLETHERMOVALVE
INTAKE MAI{IFOLD
(cont'd)
BLK
r
11-79

1. when the idls speed is out of specification and the Malfunction Indicator Lamp (MlLldoes not blink Diagnostic Trou-
ble Code (DTC) 14, check the tollowing items:. Adiust the idle speed {see page I1-95). Air conditioning signal (see page l1-84). ALT FR signal (see page '11-86)
A/T gea, position signal (see page 11-88)
Erake switch signal (see page 1 1-90)
Starter switch signal (see page 1l-921
PSP switch signal (see page 1 1-93)
Fast idl6 thormo valve (see page l1-94)
Hoses and connsctions
IAC valve and its mounting O-rings
2. lf the above items are normal, substitute a known-good IAC vslv€ and readjust the idle speed (see page 11-95)'
. It the idle speed srill cannot be adjusted to speciJication (and the MIL does not blink code 14) after IAC valve
roplacement, substitute a known-good ECM and recheck. It symptom goes away, replsce the original ECM.
1 1-81