Honda Civic 1998 Service Manual page 277

(From page 11-88)
Chcck th. ECM input vohego {lP-/
VS- lino):
1. Turn the ignition switch OFF.
2 Turn the ignition switch ON {ll).
3 . M e a s u r e v o l t a g e b e t w e e n
ECM connector terminals C24
a n d D ' ] 1 .
l s t h e r e m o r e t h a n 0 . 5 V ? Ch6ck the ECM:
1. Turn the ignition switch OFF.
2. Disconnect ECM connector C
{31P) from the ECM.
3. Check for continuity between
b o d y g r o u n d a n d E C M c o n
nector terminal C24.
-
R e p a i r o p e n i n t h e w i r e
between ECM lc24l and Pri-
mary HO2S (Sensor 'l I.
-
Substitute a known-good ECM
and .ach.ck. It symptom/indi-
cation goes awey, replace the
originalECM.
Chock tor s short in the wire (lP-l
V9- linel:
1. Disconnect the 8P connector
from the Primary HO2S (Sen'
s o r ' l ) .
2. Check for continuity between
body ground and ECM connec-
tor terminal C24.
Repl.c. the Primary HO2S {Sen-
s o . 1 ) .
Chock tho ECM output voltage
IVS+ linol:
Measure voltage between ECM
connector terminals C25 and D'11.
Check for a sho.l in tho wire {VS+
linel:
1. Turn the ignition switch OFF-
2. Disconnect ECM connector C
(31P)from the ECM.
3. Check for continuity between
b o d y g r o u n d a n d E C M c o n -
nector terminal C25.
ls there morethan 0.5 V?
ECM CONNECTORS
c {31P}
o {16P}
IP-/VS- {REDI
R6pair short in the wi.e between
the Primarv HO2S {Sensor'l) and
ECM tc24t.
f e m a l e t e r m i n a l s
sG2
{GRN/BLI(}
{cont'd)
1 1 - 8 9
3 a
5 6
1 8 9 l 0
1 1
1 2 t 3
1 a 1 5 l 6 1 1 1 8 22
23 21 25
27 2t
z)
30
o-\ rP-/vs-
7 rneot
1 2 3
1 5
8
t 0
1 1 l 2 1 3 1 4 1 5 1 6 1 7 1 8
,/
?2
23 2a
25 21 2A
a
30
fr) {RED}
1
I
8 1 0
1 1
1 2 1 3
1 4
1 5 1 6 1 7 1 8 22
23
21 25
21
2a
8 30
O) vs*
! twHTt
(To page 11-90)
(To page 11-90)