unit test HONDA CIVIC 1996 6.G Repair Manual

Gauges (cont'd)
- How the Gircuit Works
When the ignition switch is in ON (ll) or START (lll),
battery voltage is supplied through fuse 25 to the
gauges in the gauge assembly.
Speedometer and Odometer
The odometer and soeedometer drive circuits
receive pulses from the vehicle speed sensor
(VSS). The pulse rate increases as the car
accelerates. The frequency and duration of these
input pulses are measured and displayed by the
speedometer, odometer and tripmeter.
Tachometer
The tachometer drive circuit receives pulses from
the ignition control module (lCM) in the distributor
assembly or the ECM/PCM. The solid-state
lachometer then displays these pulses as engine
speed. For each 200 pulses per minute from the
ignition control modul€ (lCM) or the ECM/PCM, the
tachometer displays 100 RPM.
Engine Coolant Temperature Gauge
The engine coolant temperature gauge has two
intersecting coils wound around a permanent
magnet rotor. Voltage applied to the coils, through
fuse 25, generates a magnetic lield. The magnetic
field, controlled by the coolant temperature sending
unit, causes the rotor to rotate and the gauge
needle to move. As the resistance in the sending
unit varies, current through the gauge coils
changes. The gauge needle moves toward the coil
with the strongest magnetic field.
The 6ngine coolant temperature sending unit's
resistance varies from about 137 ohms at low
engine temperature to between 3H6 ohms at high
temperature (radiator fan running).
Refer to the Service Manual (Section 23, Electrical)
for specific tests or troubleshooting procedures.
81-2
(
Fuel Gauge (All except cX)
The fuel gauge has two intersecting coils wound
around a permanent magnet rotor. Voltage applied
to the coils, through tuse 25, generates a magnetic
field. The magnetic field, controlled by the fuel
gauge sending unit, causes the rotor to rotate and
the gauge needle to move. As the resislance in the
sending unit varies, current through the gauge coils
changes. The gauge needle moves toward the coil
with the strongest magnetic field.
The fuel gauge sending unit's resistance varies
from about 2-5 ohms at full, to about 110 ohms at
empty. When you turn the ignition switch off, the
gauge remains at the last reading until you turn the
ignition switch to ON (ll) or START (lll) again,
Refer to the Service Manual (Section 23, Electrical)
for specific tests or troubleshooting procedures.
Fuel Gauge (GX)
The fuel gauge has two intersecting coils wound
around a permanent magnet rotor. Voltage applied
to the coils, through fuse 25, generates a magnetic
field. The magnetic field, controlled by the PCM,
causes the rotor to rotate and the gauge needle to
move. The PCM calculates the gas quantity in the
fuel tank by using the fuel pressure value detected
by the tuel tank pressure sensor and the fuel
temperature value detected by the fuel tank
temperalure sensor, and outputs the signal to the
gauge assembly. The gauge needle moves toward
the coil with the strongest magnetic field.
When you turn the ignition switch off , the gauge
remains at the last reading until you turn the ignition
switch to ON (ll) or START (lll) again. When the
PCM detects a malfunction with the fuel pressure or
temperature, or detects a gas leak, the PCM
reduces the fuel meter to 0.
Refer to the Service Manual GX Supplement
(Section 11 , Fuel and Emissions) for specific tests
or troubleshooting procedures.
a
a

Front WiperMasher (cont'd)
- How the Circuit Works
When the ignition switch is in ON (ll) or START (lll),
battery voltage is applied to lhe combination wiper
switch. and the windshield wiDer motor.
Low Speed
When you turn the wiper switch to LO, the wiper
motor's low speed winding is grounded through the
BLU wire and the LO speed contacts of the wip€r
switch at G401, and the wipers run at low speed.
ParUOfl
When you turn the wiper switch OFF, the integrated
control unit (PARK input) grounds the wiper motor
through the BLUMHT wire. The cam switch on the
motor signals the integrated control unit that the
wipers are in the PARK position; the control unit
then removes ground from the motor, and the
wipers stop in the PARK position.
High Speed
When the wiper switch is in Hl, the high speed
windings of the windshield wiper motor are
grounded through the BLUIrEL wire and the Hl
contacts of the wiper switch at G401, and the
wipers run at high speed.
Intermittent
When the wiper switch is in lNT, battery voltage is
applied through the YEUBLU wire to the integrated
control unit (lntermittent wiper ON input). The
integrated control unit (lnt€rmittenvPark Wiper
Control) grounds the low speed windings of the
wiper motor and the wipers make a single sweep
every few seconds (See Low Speed above). When
the wiper retums to the PARK position, the park
switch applies battery voltage through the
BLUMHT wire to the integrated control unit (PARK
input), and the wipers stop in the PARK position.
Mist
When you pull the wiper switch down to MIST
position, the high speed windings ot the wiper motor
are grounded through the BLU^/EL wire and the
closed contacts ot the mist switch at G401, and the
wipers make one pass across the windshield at high
speed. The ParUOff function then takes over and
the wipers stop in the PARK position.
Washel
When you pull the wiper switch toward you to turn
on the washer switch, battery vollage is applied to
the washer motor. The motor pumps fluid onto the
windshield until you release the lever; on '98r99
models, the integrated control unit (windshield
washer ON input) s€nses power at the WHT/BLK
wire terminal and runs the wipers whenever the
washer motor runs.
Refer lo the Service Manual (Seclion 23, Electrical)
for specific tests or troubleshooting procedures.
91-2

Headlights (cont'd)
- How the Circuit Works
Low Beams
With the headlight switch in HEAD and the dimmer
switch in LO, current tlows through the headlight
switch. fuse 21 . fuse 22. and the low beam
tilaments to ground, and the low beams come on.
High Beams
With the headlight switch in HEAD and the dimmer
switch in Hl, current flows through the headlight
switch, dimmer switch, fuses 4, 5, and the high
beam filaments to ground, and the high beams
come on.
Current also llows through the high beam indicator
light to ground. The high beam indicator comes on
to remind the driver that the high beams are on.
Flash-to-Pass
The flash feature works with the headlight switch in
OFF, PARK, or HEAD (low beams). When you move
the flash-to-pass switch to ON, current flows
through the switch, fuses 4 and 5, and the high
beam filaments to ground, and the high beams
flash. The high beam indicator also flashes during
the flash operation. The flash function has no effect
if the high beams are already on
Daytime Running Lights (Canada)
When you turn the ignition to ON (ll) with the
parking brake released, the daytime running lights
control unit supplies battery voltage at the
WHT/RED wire. This voltage is applied to the high
beam headlights through the daytime running lights
resistor. Each high beam headlight receives less
than battery voltage causing them to come on at
reduced brightness.
lf the parking brake is set, a ground signal is applied
to the daytime running lights control unit at the
RED/GRN wire. lf the parking brake is set when you
first turn the ignition switch to ON (ll), the high beam
headlights will remain off until you release the
parking brake. Once the high beam headlights are
on, setting the parking brake will not turn them ofi.
When low or high beam operation is requested,
battery voltage from the headlight switch is applied
to the daytime running light control unit via the RED
wire. The daytime running lights control unit then
turns off the headlights.
Refer to the Service Manual (Section 23, Electrical)
for specific tests or lroubleshootrng procedures.
110-14

Power Windows (contd)
- How the Circuit Works
CAUTION: You could iniure your arms, hands, or
fingers if you unintentionally switch the driver's
window to "automatic down" while working in
that door with the power on. Disconnect the
window switch conneclot or the battery when
working in the driver's door.
System Description
The operation of the power windows is controlled by
the main switch in the power window master switch.
When the main switch is in OFF, only the driver's door
window can be opened or closed. With the main
switch ON, all windows can be ooened or closed
either by swtches in the master panel, or swttches in
the doors. The driver's window switch also has an
automatic down mode which is tumed on by pushing
the switch down to its second oosition.
The power windows are driven by reversible motors.
Each motor is protect€d by a built-in circuit breaker.
lf the window switch is held on too long (with the
window obstructed, or after the window is fully up or
down), the circuit breaker opens the circuit. The
circuit breaker resets automaticallv as it cools.
Driver's Window
With the ignition switch in ON, voltage is provided to
the coil of the power window relay through fus€ 24.
The contacts of the power window relay close, and
voltage is applied to the driver's switch. When you
push the power window master switch to UP, voltage
is applied to the driver's window motor. (The motor's
ground path is back through the master power
window switch.) The driver's window motor then
drives the window up. When you push the switch to
DOWN, voltage is applied in the opposite direction
and the motor drives the window down.
Automatic Down (Driver's Window)
With the ignition switch in ON or START, voltage is
applied to the coil of the power window relay. The
contacts of the power window relay close and
voltage is applied lo the power window master
switch. When you push the driveas switch to the
AUTO DOWN position, voltage is applied through
the driver's switch to the driver's window motor. The
control unit receives pulses at the pulser input while
the motor is running. When the window is fully
down, the motor stops, and pulses are no longer
generated by the pulser. This is sensed by the
control unit at the pulser input, and voltage is no
longer applied to the driver's window motor.
Passenger Windows
With the ignition switch in ON, voltage is applied to
the coil of the power window relay through fuse 24.
The contacts of the power window relay then close,
applying voltage to the individual window switches
and the power window master switch. With the
master panel main switch ON, the passenger
windows can be ooerated from the individual
window switches or from tho master panel switches.
When you push the front passengsr's window
switch to UP, voltage is applied to the f ront
passenger's window motor. (The motor is grounded
through the contacts in the front passenger's
window switch and the oower window master
switch.) The window moves up as long as you hold
the switch in the UP position. lf you push the switch
to DOWN, voltage is applied in th€ opposite
direction to the front passenger's window motor, and
the window movss down as long as you hold the
switch in the DOWN Dosition. The window switches
in the other doors operate similarly.
When you push the front passenger's switch in the
master panel to UP, voltage is applied through the
front passenger's window switch contacts to the
front passengefs window motor. (The motor is
grounded through the contacts in the front
passenger's window switch and the power window
master switch.) The window moves up as long as
you hold the switch in the UP position. lf you push
the switch to DOWN, voltage is applied in the
opposite direction to lhe front passenger's window
motor, and the window moves down as long as you
hold the switch in the DOWN position. The other
passenger window switches in the master panel
operate similarly.
Refer to the Service Manual (Section 23, Electrical)
for specific tests or troubleshooting procedures.
120-4

Keyless Receiver Unit Troubleshooting
lf a faulty keyless receiver unit has one of the symptoms below, turn to the page listed and follow the
appropriate troubleshooting procedure. lf the symptom seems related to an input problem, or is not covered
by the troubleshooting procedures, do the Input Tests on page 130-6. Refer to the circuit schematic on pages
1 30-2 and 130-3 as needed.
Symptom Index
Keyless Entry Does Not Work In Any Mode
Ceiling Light Does Not Come On When The Doors Are Unlocked
WithTheTransmitter ....
Doors Do Not Unlock Or Lock With The Transmitter . . . .
Horn Does Not Sound With The Transmitter "Beeo" Feature On
Horn Does Not Stop Sounding .......
Input Tests
Page 130-8
Page 130-9
Page 130-1 0
Page 130-11
Page 130-11
Page 130-11
Page 130-6
.1,

Power Door Locks (cont'd)
Keyless Receiver Unit Input Test
The following tests are pertormed with A (Main) and B (Keyless) disconnected from the audio unit.
TerminalNo.WireColorTest ConditlonTest: Desired RasultPossible Cause it resull is not obtained
4WHT/BLUUnder all conditionsCheck for vollage to ground:
There should bs batteryvoltage.
aBlown No. 47 (7.5A) tuse in the
under-hood fuss/relay box
An open in the wireo
5YEUREDlgnition switch ACC (l)Check lor voltage to ground:
Th€re should be battery
voltage.
aBlown No. 28 (10A) fuse in the
underdash fusg/relay box
An open in the wirea
TerminalNo.WireColorTest CondiiionTest: Desired ResultPossible Cause if rssult i3 not obtalned
BLU/RED
lgnition key insertedinto the ignition key
switch
Check for voltage to ground:
There should bs 1 V or less.aPoor ground (G401, G402)
Faulty ignition key switch
An open in the wire
Short in the wire
a
a
algnition key r€moved
trom the ignition key
switch
Check lor voltage to ground:
There should be 4 V or more.
3BLUI/ELUnder all conditions
Check for continuity betweenthe audio unit 16P connectorNo- 3 terminal and power doorlock control unit 12P connsctorNo. 6 terminal: There should
be continuity.
I An open in the wire
6BLK/YELlgnition switch ON (ll)Check for voltage to ground:
Thers should be batteryvollage.
. Blown No. 14 (7.5A) fuse in the
under-dash fuse/relay box
. An open in the wire
8LT GRN/BLKCeiljng light switch in"middle position"Connect to ground: The ceilinglight should come on.
aBlown No. 43 (7.5A) fuse in the
undsr-hood fuse/relay box
Blown ceiling light bulb
Faulty ceiling light
An open in the wire
a
a
o
14LT GRN/REDEach door oponed,one at a timeCheck for continuity to ground:
There should be continuity.
aFaulty door switch
An open in lhe wirea
tcBLKUnder all conditionsCheck for continuity to ground:
There should b€ continuity.
aPoor ground (G401, G402)
An open in the wirea
16GRYUnder all conditionsConn€ct to ground:
Horn should sound.
. Blown No.52 (15A) fuse in the
under-hood tuse/relay box
. Faulty horn
. Faulty horn relay
. An open in the wire
130-6

\
The following tests are performed with A (Main) reconnected to the audio unit.
B
\
TerminalNo.WireColorTest CondilionTest: Desired ResultPossible Cause it result is not obtained
9GRN/ORN
Driver's door lockswitch in UNLOCKCheck tor voltage to ground:There should be l V or less.
o Poor ground (G551)
. Faulty driver's door lock switch
. An open in the wire
. Short in the wire
Driver door lockswitch in LOCKCheck for voltage to ground:
There should be 4 V or more.
10GRN/vvHT
Driver's door lockswitch in UNLOCKCheck for voltage to ground:
There should be 4 V or more.
r Poor ground (G551)
. Faulty driver's door lock switch
o An open in the wire
o Short in the wire
Driver's door lockswitch in LOCKCheck for voltage to ground:
There should be 1 V or less.
\
130-7

Power Door Locks (cont'd)
Keyless Entry Does Not Work In Any
Mode
NOTE: Before beginning, verify that all the
transmitters are programmed to the vehicle.
1 . Does the radio work properly?
Yes - Go to step 9.
No - Go to the neld step.
NOTE: For steos 2 - 8. refer to the schematic dia-
gram for the Stereo Sound System on page 150.
2. Are fuses 28 (in the under-dash fuse box) and
fuse 47 (in the under-hood fuse box) OK?
Yes - Go to step 4.
No - Replace the blown fuse, then go to the
nen steo.
3. Does the fuse blow again?
Yes - Locate and repair the short.
No- Retest the system.
4. ls the vehicle equipped with the optional security
system?
Yes - Go to the next steP.
No - Go to steD 6.
5. Does the keyless entry work correctly when the
security control unit connector is disconnected?
Yes - Faulty security system, go to security
system for f urther troubleshooting.
No - Go to the next step.
6. ls there battery voltage at terminal 4 of the radio
main harness connector (A)?
7.
=A
Yes - Go to the nen step.
No - Locate the open in the wiring between
tuse 47 and the radio.
ls there battery voltage at terminal 5 of the radio
main harness connector (A), when the ignition
switch is in the ACC (l) or ON (ll) position?
Yes - Go to the next step.
No - Locate the open in the wiring between
fuse 28 and the radio.
130-8
8. ls there continuity from terminal 14 of the radio
main harness connector (A) to ground?
Yes - Replace the radio.
No - Repair the open in the wiring between the
radio and the ground (G501).
9. Does the transmitter LED come on when any ot
the buttons are oressed?
Yes - Go to steo 12.
No - Go to the next steo.'10.ls the transmitter battery installed with the
positive side facing up?
Yes - Ensure that the battery contact tabs are
repositioned, then replace the battery.
Remove the key from the ignition, then
close the doors and trunk. Press the
LOCK button on the transmitter six times,
then go to the next step.
No - Ensure that the baftery contact tabs are
repositioned, then reinstall the batlery
correctly. Then reprogram the transmitter
and retest it. Use the procedure on page
1 30-4 f or transmitter programming.
11 . Does the transmitter LED come on when any of
the buttons are oressed?
Yes - Go to the next step.
No - Replace the transmitter and program it by
using the procedure on page 130-4.
12.Does the system work properly in all modes?
Yes - Finished. The system is OK.
No - Go to the next steD.

a
Horn Does Not Sound In The Panic
Mode Or With The Transmitter "Beep"
Feature On
NOTE: The transmitter has a Beep On/Off feature.
Refer to page 130-4 for how to tum the beep on or
off.
1. Does the horn sound when the HORN button is
oressed?
Yes - Go to the next steD.
No - Repair the horn circuit.
2. Does the transmittor LED come on when any of
the buttons are pressed?
Yes - Go to the next step.
No - Check the transmitter battery then retest.
ll the beep feature still does not work, go
to the next steo.
3. Recheck with a known good transmitter
reprogrammed to the vehicle. Does the system
work properly in all modes?
Yes - Replace and program the transmitter,
then retest. Use the procedure on page
1 30-4 f or transmitter programming.
No - Go to the next step.
4. With the keyless entry harness connector (B)
disconnected from the radio, run a.iumper wire
f rom terminal 16 to ground.
Does the horn sound?
Yes - Reglace the radio.
No - Repair the open in the terminal 16 (GRY)
wire.
\
Horn Does Not Stop Sounding
1. ls the vehicle equipped with the optional security
system?
Yes - Go to the next step.
No - Go to step 3.
Do€s the horn stop sounding when the security
control unit connector is disconnected?
Yes - Replace the security control unit.
No- Go to the next step.
Does the horn stop sounding when the keyless
entry harness connector (B) is disconnected?
Yes - Reolace the radio.
No - Reoair the hom circuit.
130-11

Keyless Receiver Unit Troubleshooting
lf a faulty keyless door lock control unit has one of the symptoms below, turn to the page listed and tollow the
appropriate troubleshooting procedure. lf the symptom seems relatod to an input problem, or is not covered
by the troubleshooting procedures, do the Input Tests on page 130-16. Refer to the circuit schematic on
pages 130-12 and 130-13 as needed.
Symptom Index
Keyless Entry Does Not Work In Any Mode
Ceiling Light Does Not Come On When The Doors Are Unlocked
With TheTransmitter ....
Doors Do Not Unlock Or Lock With The Transmitter . .
Horn Does Not Sound With The Transmitter 'Beep" Feature On .........
Horn Does Not Sound In The Panic Mode ..
HornDoes NotStopSounding ...............
Page 1 30-17
Page 130- 18
Page 130-1 I
Page 130-19
Page 130-19
Page 1 30-19
Page 130-16Input Tests
\.
130-15