2003 HONDA CIVIC Front

sRs
Precautions and Procedures (cont'dl
Disconnecting System Connectors
Before removing a front airbag. side airbag, or other SRS related devices {the SRS unit, the cable reel, the front impact
sensors, the side impact sensors, the seat belt buckle tensioners, and the seat belt tensioner connector), disconnectingconnectors from related devices, or removing the dashboard or the steering column, disconnect the airbag connectorsor the side airbag connectors to prevent accidental deploVment.
Turn the ignition switch OFF, disconnect the negative cable from the battery, and wait at least 3 minutes before
beginning the following procedures.'BeforedisconnectingSRSunitconnectorA(1)fromtheSRSunit,disconnectthedriver'sairbag4Pconnector(3).
the front passenger's airbag 4P connector (4), the driver's seat belt tensioner 2P connector (6), and the frontpassenger's seat belt tensioner 2P connector (7).
. Before disconnecting SRS unit connector B (8) from the SRS unit, disconnect both side airbag 2P connectors (11. '12),
and both seat belt buckle tensioner 4P connectors (9, 10).. Before disconnecting the cable reel 4P connector (2), disconnect the driver's airbag 4P connector (3).'Beforedisconnectingthefloorwireharness4Pconnector(5),disconnectbothseatbelttensioner2Pconnectors
(6.7).
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1. Disconnect the battery negative cable, and wait at
least 3 minutes.
Driver's Airbag
2. Remove the access panel (A) from the steering
wheel, then disconnecl the driver's airbag 4P
connector (B)from the cable reer.
Front Passenger's Airbag
3. Disconnect the front passenger's airbag 4P
connector (A)from dashboard wire harness B.
Side Airbag
4. Disconnect both side airbag 2P connectors (Alfrom
the floor wire harness.
(cont'd)
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General Troubleshooting Information
DTC (Diagnostic Trouble Codesl
The self-diagnostic function of the SRS system allows it
to locate the causes of system problems and then store
this information in memory. For easier troubleshooting,
this data can be retrieved via a data link circuit.
. When you turn the ignition switch ON (ll), the SRS
indicator will come on. lf it goes off after 6 seconds,
the system is normal.. lf there is an abnormality, the svstem locates and
defines the problem, stores this information in
memory, and turns the SRS indicator on. The data
will remain in the memory even when the ignition
switch is turned off or if the battery is disconnected.. When you connect the Honda PG lM Tester to the 16P
data link connector (DLC)to short the SCS terminal,
and turn the ignition switch ON (ll). the SRS indicator
will indicate the diagnostic trouble code (DTC) by the
number of blinks.. When you connect the Honda PGM Tester to the 16P
data link Connector (DLC), you can retrieve the DTC in
the Honda Systems "SRS" menu.. After reading and recording the DTC, proceed with
the troubleshooting procedure for th is code.
Precautions. Use only a digital multimeter to check the system. lf
it's not a Honda multimeter, make sure its output is
10 mA (0.01A) or less when switched to the smallest
value in the ohmmeter range, A tester with a higher
output could damage the airbag circuit or cause
accidental airbag deployment and possible injury.. Whenever the ignition switch is ON (ll), or has been
turned OFF for less than 3 minutes, be careful not to
bump the SRS uniU the airbags could accidentally
deploy and cause damage or injuries.. Before you remove the SRS harness, disconnect the
driver's airbag connector. the front passenger's
airbag connector, both side airbag connectors, both
seat belt buckle tensioner connectors, and both seat
belt tensioner connectors.. Make sure the battery is sufficiently charged. lf the
battery is dead or low, measuring values won't be
correct.. Do not touch a tester probe to the terminals in the
SRS unit or harness connectors, and do not connect
the terminals with a jumper wire. Use only the
backprobe set and the Honda PGM Tester. Backprobe
spring loaded lock type connectors correctly.
Reading the DTC
When the SRS indicator is on, read the DTC using either
of the following methods:
PGM Tester "SRS" Menu Method:
Connect the Honda PGM Tester {A) to the 16P data link
connector {DLC)(B), and follow the Tester's Drompts in
the "SRS" menu.
lf the Tester indicates no DTC, no communication. DTC
3-6 to 3-'10, DTC 4-6 to 4-10, DTC 9-1, or DTC 9-2,
double-check by using the "SCS" menu method.
(cont'd)
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I
Initializing the OPDS {Occupant Position Detection System} Unit
Special Tool Required
SCS service connector 07PAz-00'1 01 00
When a seat-back cover, seat-back cushion, and/or OPDS unit is replaced, initialize the OPDS by following theprocedure below.
NOTE: Make sure the front passenger's seat is dry. Set the seat-back in the normal position, and make sure there isnothing on the seat.
'1. l\4ake sure the ignition switch is OFF.
2. Connect the Honda PGM Tester (A) to the DLC (16P) (B), andfollowtheTester's prompts jn the ,,SCS,, menu toground the SCS line (see the Honda PGM Tester Operator's ManuaD.
3. Connect the SCS service connector (C) to the MES 2P connector (D). Do not use a iumoer wire.
c07PAZ-00r0100
4. Turn the ignition switch ON {ll).
5. The SRS indicator comes on for about 6 seconds and goes off. Remove the SCS service connector from the MESconnector within 4 seconds after the SRS indicator went off.
6. The SRS indicator comes on again. Reconnect the SCS service connector to the MES connector within 4 secondsafter the SRS indicator comes on.
7. The SRS indicator goes off. Remove the SCS service connector from the MES connector withln 4 seconds.8. Watch the sRS indicator.'lftheindicatorblinkstwotimesandthenstayson,theOPDSisinitialized.buttheDTCSneedtobeerased.Goto
step 9, then erase the DTCS..lftheindicatorblinkstwotimesandthengoesoff,theOPDSunitisinitialized.Gotostep9.
' lf the indicator stays on without first blinking.the OPDS is not initialized. Readthe DTC. lf DTC 15-'l is indicated,repeat the initialization procedure. lf another DTC is indicated, go to the appropriate page in the DTCTroubleshooting Index.
9. Turn the ignition switch off, and disconnect the PGM Tester.
SBS indic.ror
MES
IJ
DISCONNECTED
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sRs
DTCDetection ltemNotes
t- |ODen in driver's airbaq inflator(see Daqe 23-36)
Increased resistance in driver's airbaq inflator(see Daoe 23-36
t-5Shon to another wire or decreased resistance in driver's airbag
inflator
(see page 23-37)
1-4Shortto Dower in driver's airbao inflator(see paqe 23-39
t-5Shortto qround in driver's airbaq inflator{see paqe 23-40
2-1Open in front Dassenqer's airbaq inflator{see oaoe 23-42
2-2Increased resistance in front passenqer's airbaq intlator(see oaqe 23-42
2-3Short to another wire or decreased resistance in front passenger's
airbao inflator
(see page 23-43)
2-4Short to oower in front oassenoer's airbaq inflator(see paqe 23-45
2-5Short to qround in front passenqer's airbaq inflator(see paqe 23-46
3-1ODen in driver's seat belt tensioner(see page 23-48
3-2lncreased resistance in driver's seat belt tensioner(see paqe 23-48
3-3Short to another wire or decreased resistance in driver's seat belt
tensioner
(see page 23-49)
3-4Short to oower in driver's seat belt tensioner(see Daqe 23-51
3-5Short to oround in driver's seat belt tensioner(see oaoe 23-52
21-1ODen or increased resistance in driver's seat belt buckle tensioner(see paqe 23-54
Short to another wire or decreased resistance in driver's seat belt
buckle tensioner
(see page 23-55)
2't -4Short to Dower in driver's seat belt buckle tensioner(see paqe 23-56)
2't-5Shon to oround in driver's seat belt buckle tensioner(see oaqe 23'57
4-'lODen in front oassenoer's seat belt tensioner{see page 23-58)
4-2lncreased resistance in front oassenqer's seat belttensioner{see paqe 23-58)
4-3Short to another wire or decreased resistance in front passenger's
seat belt tensioner
{see page 23-60)
4-4Shon to Dower in front Dassenqer's seat belt tensionerlsee oaqe 23-61
4-5Short to qround in front oassenoer's seat belt tensioner(see Daqe 23-63
Open or increased resislance in front passenger's seat belt buckle
tens ioner
(see page 23-64)
22-3Short to another wire or decreased resistance in front passenger's
seat belt buckle tensioner
(see page 23-65)
22-4Short to oower in front oassenqer's seat belt buckle tensioner(see paqe 23-66
22-5Short to oround in front oassenoer's seat belt buckle tensioner(see paqe 23-68
5-1lnternal failure of SRS unit
NOTE:
Before troubleshooting DTCS 5-1 through 8-6, check battery/system
voltage. lf the voltage is low, repair the cha rging system before
troubleshootino the SRS.
(see page 23-69)
5-2
5-4
5-8
6-3
6-4
6-7
6-8
1-)
7-3
8-1
a-2
8-4
8-5
8-6
DTC Troubleshooting Indext.
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DTCDetection ltemNotes9-1Internal failure of the SRS unit. lf intermittent, it could mean internalfailure of the unit or a faulty indicator circuit. Refer toTroubleshooting Intermittent Failures (see page 23-26).
NOTE: Before troubleshooting DTC 9-1 or 9-2, check battery/systemvoltage. lf the voltage is low, repair the charging system beforetroubleshooting the SRS.
(see page 23-69)
9-2Internal failure of the SRS unit. lf intermittent, it could mean internalfailu re of the power supply (VB line). Refer to TroubleshootingIntermittent Failures (see page 23-26).
NOTE: Before troubleshooting DTC 9-1 or 9-2, check battery/systemvoltage. lf the voltage is low, repair the charging system or replacethe b€ttery before troubleshooting the SRS.
9-3Faulty driver's seat belt buckle switch(see Daqe 23-71)9-4
9-6
FaultLtglt passenger's seat belt buckle switch
Faulty Ieft front imDact sensorlgqgfage 23-74)
{see Daqe 23-77)9-7Faulty right front impact sensor(see paqe 23-79)10-1Seat belt and seat belt buckle tensioners (and airbag(s)) deployedDriver's side airbag deployed
Seat belt and seat belt buckle tensioners (and airbag(s)) and driver'sside airbag deployed
Front passenqer's side airbao deDloved
(see page 23-69)10-2
r0-3
'10-4
'10-5Seat belt and seat belt buckle tensioners (and airbag(s)) and frontpassenqer's side airbaq deDloved
10-6Driver's and front passenqer's side al10-7Seat belt and seat belt buckle tensioners (and airbag(s)) and driver'sand front passenger's side airbags deployed
1 1-1Open or increased resistance in driver's side airbao inflator(see paqe 23-81)Short to another wire or decreased resistance in driver's side airbaoinflator
(see page 23-82)
11-4Short to power in driver's side airbaq inflator(see oaqe 23-83)I t-5Short to ground in driver's side airbaq inflator{see paqe 23-85)Open or increased resistance in front passenger's side airbaginflator
(see page 23-86)
Short to another wire or decreased resistance in front passenger's
side airbag inflator
(see page 23-87)
12-4Short to power in front passenqer's side airbaq inflator{see Daqe zJ-uu}I z-5Short to ground in front passenger's side airbaq inflator(see oaqe 23-90)13-1Internal failure of the driver's side impact sensor(see page 23-70)
No signal from the driver's side impact sensor(see paqe 23-91)13-4
14-1-7ii,
Faulty power supply to the df,rglllug t Opact s9I99LInternal failure ofthe front passenger's side impact sensor
(see page 23-92)(see page 23-70)
14-3No signal from the front passenger's side impact sensor(see paqe 23-94)14-4Faulty power supply to the front passenqer's side impact sensor(see page 23-95)15-1Faultv OPDS unit or OPDS not initialized(see paqe 23-96115-2Faulty side airbag cutoff indicator circuit(see Daqe 23-99)15-3Faulty OPDS sensor(see oaoe 23-104)
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ISystem Description
SRS Components
Airbags
The SRS is a safety device which, when used with the seat belt, is designed to help protect the driver and frontpassenger in a frontal impact exceeding a certain set limit. The system consists ofthe SRS unit, including safingsensor and impact sensor (A), the cable reel (B), the driver's airbag (C), the front passenger,s airbag (D). seat belttensioners (l), seat belt buckle tensioners (J), and front impact sensors (K).
Since the driver's and front passenger's airbags use the same sensors, both normally inflate at the same ttme.However, it is possible for only one airbag to inflate. This can occur when the severity of a collision is at the margin, orthreshold, that determines whether or not the airbags will deploy. In such cases, the seat belt will provide sufficientprotection, and the supplemental protection offered by the airbag would be mininal.
Side Airbags
The side airbags (E) are in each front seat-back. They help protect the upper torso of the driver or front seat passenger
during a moderate to severe side impact. Side impact sensors (F) in each door sill and in the SRS unit detect such animpact and instantly inflate the driver's or the passenger's side airbag. Only one side airbag will deploy during a sideimpacl. lf the impact is on the passenger's side, the passenger's side airbag will deploy even if there is no passenger.
Seat Belt and Seat Belt Buckle Tensioners
The seat belt and seat belt buckle tensioners are linked with the SRS airbags to further increase the effectiveness ofthe seat belt. ln a front-end collision, the tensioners instantly retract the belt and buckle firmly to secure the occupantsin their seats.
OPDS
The side airbag system also includes an occupant position detection system (OpDS). This system consists of sensors(G)and an OPDS unit (H) in the front passenger's seat-back. The OPDS unit sends occupant heighl and position data tothe SRS unit. lf the OPDS unit determines that the front passenger is of small stature (for example, a child) and thefront passenger is leaning into the side airbag deployment path, the SRS unit will automatically disable the passenger'sside airbag. The SRS unit will also disable the airbag when the OPDS detects certain obiects on the seat. When theside airbag is disabled, the side airbag cutoff indicator on the instrument panel alerts the driver that the passenger'sside airbag will not deploy in a side impact. When the object is removed, or the passenger sits upright, the side airbagcutoff indicator will go off after a few seconds, alerting the driver that the passenger's side airbag will deploy in a sideimDact.
(cont'd)
I
23-31

sRs
System Description (cont'dl
SRS Operation
The main circuit in the SRS unit senses and judges the force of impact and, if necessary. ignites the inflator charges. lf
battery voltage is too low or power is disconnected due to the impact, the voltage regulator and the back-up power
circuit, respectively, will keep voltage at a constant level.
For the SRS to operate:
Seat Belt Tensioners and Seat Belt Buckle Tensioners
(1) A front impact sensor must activate and send electric signals to the microprocessor.
(2) The microprocessor must compute the signals and send them to the tensioners.
(3) The charges must ignite and deploy the tensioners.
Driver's and Front Passenger's Airbagls)
(1) A front impact sensor musl activate. and send electric signals to the microprocessor.
(2) The microprocessor must compute the signals. and depending on the severity of the collision and whether the seat
belt buckle swilch is ON or OFF, it sends the appropriate signals to the airbag inflator(s).
(3) The inflators that received signals must ignite and deploy the airbags.
Side Airbaglsl( 1) A side impact sensor must activate, and send electric signals to the microprocessor.
(2) The microprocessor must compute the signals and send them to the side airbag inflator(s). However, the
microprocessor cuts off the signals to the front passenger's side airbag if the OPDS unit determines that the tront
passenger's head is in the deployment path of the side airbag.
(3) The inflator that received the signal must ignite and deploy the side airbag.
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23-32
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