Honda Civic 2002-2003 Service Manual page 1007

Multiplex Control System
Multiplex Control Unit Input Test (cont'd)
3. Inspect the connector and socket terminals to be sure they are all making good contact.
• If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system .
• Ifthe terminals look OK, go to step 4.
Cavity
Wire
Test condition Test: Desired result Possible cause
if
result is not obtained
J4
BLK Under all conditions Check for voltage to ground: • Poor ground (G201)
There should be 1Vor Jess. • An open in the wire
Y6 BLK Under all conditions Check for voltage to ground: • Poor ground {G501}
There should be 1 V or less. • An open in the wire
Y1 BRN/YEL
: Parking brake lever ' Check for voltage to ground:
• An open in the wire
down, turn the There should be battery voltage
Short to ground
igntion switch ON (II) while the Brake system indicator is Faulty ABS modulator-control unit
on for the buld check.
Check for voltage to ground:
There should be 1 V or less when the
I
Brake system.
J2
WHT/RED Under all conditions Check for voltage to ground: I • Blown No.9 (lOA) fuse in the under-hood
There should De battery voltage.
I
fuse/relay box
o
An ODen in the wire
4. Reconnect the connectors to the under-dash fuse/relay box, and make sure these input tests at the appropriate connectors on the under-
dash fuse/relay box.
If any test indicates a problem, find and correct the cause, then recheck the system.
o
If all the input tests prove OK, the multiplex control unit must be faulty. Replace the under-dash fuse/relay box assembly.
Cavity
I
Wire Test condition Test: Desired result Possible cause if result is not obtained
Q3
GRN
Driver's door open Check for voltage to ground: Faulty driver's door switch
There should be 1 V or less. An open in the wire
Driver's door closed Check for voltage to ground:
o
Faulty driver's door switch
There should be 5 V or more.
I
o
Short to ground
04
LT GRN/RED
Passenger's door Check for voltage to ground:
o
Faulty passenger's door switch
open There should be 1 V or less.
o
An open in the wire
I Passenger's door , Check for voltage to ground:
o
Faulty passenger's door switch
. dosed There should be 5 V or more .
o
Short to around
08
GRN/ORN Parking brake lever Check for voltage to ground:
o
Faulty parking brake switch
uo
There should be 1 V or less.
o
An ooen in the wire
C8 GRN/ORN Parking brake lever
Che~k
for voltage to ground:
o
Faulty parking brake switch
down There should be 5 V or more.
o
Short to ground
F1
GRN/RED
(USA)
F8
GRN/ORN
(Canada)
,
GRN/RED
05
BLU/RED Ignition switch ON (II), Check for voltage to ground:
o
Faulty driver's seat belt switch
I
driver's seat belt is
There should be 1 V or less.
o
Poor ground (G551)
unbuckled.
o
An open in the wire
06
\
BLU/RED Ignition switch ON
(II),
Check for voltage to ground:
I
o
Faulty driver's seat belt switch
I
driver's seat belt is
I
There should be 6 V or more.
Short to ground
buckled.
P18
I
RED
CChopen
Check for voltage to ground: Faulty hatch latch switch
,
I
There should be
1
V or less.
Poor ground (G552)
-
An o"pen in the wire
Hatch closed Check for voltage to ground:
o
Faulty hatch latch switch
There should be 5 V or more
o
Short to Qround
X5
RED/WHT
I Ignition key in the I
Check for voltage to ground:
I
0
Faulty ignition key switch
ignition switch There should be 1 V or less.
I
0
Poor ground (G401)
o
An o'p_en jn the wire __
~nftion
key out of the
cfleck
for voltage to ground: Faulty ignition key switch
ignition switch There should be 5 V or more.
o
Short to ground
22-176
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