Honda Civic Service Manual page 478

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 (ALT
F linel:
1. oisconnect the 4P (3P)* con-
nector from the ALT.
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
E C M / P C M c o n n e c t o r t e r m i
nals C17 and A9.
Check lor a sho.t in the wire {ALT
F 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 con
nector C {31P).
4. Check for continuity between
b o d y g r o u n d a n d E C M / P C M
connector 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 . 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) untjl
the radiator fan comes on, then
let it idle.
4. [,4easu re voltage between
ECM/PCM connector terminals
C17 and A9.
Repair short in the wire betwe€n
the ECM/PCM {Cl71and th€ ALT.
Substitute a known-good ECM/
PCM and recheck. It prescribed
voltage is now available, roplace
the originrl ECM/PCM.
Does the voltage decrease when
h e a d l i g h t s a n d r e a r d e f o g g e r a r e
t u r n e d o n ?
ALT FR signal is OK.
Check tor an open in the wire (AlT
F linel:
1. Turn the ignition switch OFF.
2. Disconnect the negative bat-
tery cable from the battery.
3 . D i s c o n n e c t t h e E C M / P C M
connector C (31P).
4. Disconnect the 4P (3P)* con,
nector from the ALT.
5. Connect the ALT 4P 13P)l con
nector terminal No. 4 (No. 1)'
to body ground with a iumper
6. Check lor continuity between
b o d y g r o u n d a n d E C M / P C M
connector terminal C17,
Repair op6n wire botween th€
ECM/PCM (C171rnd th€ ALT.
ls there continuity?
c {31P)
1
1
7
8
I
1 0
1 1
12 1 3
1 4
1 5 1 6 1 7 1 8
23
21 25
a
30
o ALT F IWHT/REDI
4P
3P*
1 2 l
Flr
rr-ri-f
rwHr/ (V)
neor Y
* : C a n a d a m o d e l
11-208
3
I
7
8
9 1 0
1 l 1 2 1 3
l 4
1 5 1 6
1 7
1 8
/l
23 21 25
E 30
o ALT F IWHT/REDI