Honda Civic Service Manual page 424

PGM-FI System
I
a
a
9ggoqOfry Heated Oxygen Sensor (Secondary HO2S) {sensor 2l
('96 - 98 Models; '99 - 00 D16YS engine with M/Tl
The scan tool indicates Diagnostic Trouble Code (DTC) PO'138: A high voltag€ problem in the Secondary Heated
Oxygen Sensor (Secondary HO2SI (sensor 2) circuit.
SECONDARY HO2S ls.nsor 2l
4P CONNECTOR C125 tc782t*
JUMPER WIRE
sHo2s
IWHT/RED}
sHo2sG
(RED/YEL)
(GRN/WHT)*
(GRN/BLK)*'
Wire side of female terminals
ECM/FCM CONN€CTOR D Il6PI
sH()2sG
{YEL/RED)
{GRN/BLK}'
JUMPER WINE
Wire side of female terminals
' i
D 1 6 Y g e n g i n e
* 1 i D l 6 Y 5 e n g i n e
-
Ths MIL ha3 bcen r6port.d on.
-
DTC m138 i. 3tored.
Problem vorilication:
1. Do the ECM/PCM Reset Pro-
cedure.
2 . S t a r t t h e e n g i n e . H o l d t h e
engine at 3.000 rpm with no
load (in Park or neutral) until
the radiatorfan comes on.
3. With the scan tool, ch€ckthe
S e c o n d a r y H O 2 S { S e n s o r 2 )
outputvoltageat 3,000rpm.
Into.mittant failurc, sy3tem b OK
rt thi3 tims. Ch6ck tor poor con-
n6clionr or loo3€ wiroa at C13'l*
(locat d und6r right lido of dr'h),
C/€2r (loc.tod und€r middle ol
d.rhl, C125 {C782lr (Socond.ry
HO2S S6n3or 2) .nd ECM/PCM.
Chcd( for rn open in the Socond!ry
f|o2s:
1. Turn the ignition switch OFF.
2 . D i s c o n n e c t t h e S e c o n d a r y
HO2S (Sensor 2) 4P connector.
3. Connect the Secondary HO2S
(Sensor 2) 4P connector ter-
minals No. 1 and No.2 with a
JUmper wire.
4. Tu.n the ignition switch ON (ll).
5 . C h o c k t h e S e c o n d a r y H O 2 S
(Sensor 2) output vollage with
the scan tool.
ls there 0.6 V or more?
Check tor an open in the wiro
(SHO2S lin6l:
1. Turn th6 ignition switch OFF.
2. Connect ECM/PCM connector
terminals D14 and D13 with a
jumper wire.
3. Turn the ignition switch ON {ll}.
4 . C h e c k t h e S e c o n d a r y H O 2 S
( S e n s o r 2 ) o l t p u t v o l t a g e
with the scan tool.
Rapair op.n in the wiio botw.on
ECM/PCM lD13 and/or Dlal and
S.cond.ry HO2S ls€nsor 21.
ls thore 0.6 V or more?
Subslituto a known-good ECM/
PCM .nd rccheck. lt symptom/
indication goe! rway, replace
the original ECM/PCM.
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