1997 HONDA CIVIC signal light

tAlternator (ALT) FR Signal ('99 - 00 Models except Dl6Y5 engine with M/T)
This signals the ECM/PCM when the Alternator {ALT) is chargingECM/PCM CONNECTORS
Wire side of female terminals
ECM/PCM CONNECTOR C (31P}
lt
lP
ALT CONNECTORS IClO4I
JUMPER
JUMpER WlnE
WIRE
Wire side of female termlnals
ECM/PCM CONNECTOR C (31PI
3P*NO
Check lor an op€n in the wire (ALT
F line,:1. Turn the agnition switch OFF
2. Disconnect the negative bat-
tery cable {rom the battery.
3. Disconnect the ECM/PCM con'
nector C (31P).
4. Disconnect the 4P (3P)* con'
nector from the ALT.
5. Connect the ALT 4P (3P)* con-
nector terminal No 4 (No. 1)*
to bodY ground with a iumper
6. Check lor continuity between
body ground and ECM/PCM
connector terminal C5
--?--1l2l|#i3l.l
otriJrwxrr (V)
neor Y
lnsoeclion oI ALT FB Signal.
Check {or a short in the wire {ALT
F line):1. Disconnect the 4P (3P)+ con
nector from the ALT
2. Turn the ignition switch ON (ll)
3. Measurc voltage between EcM/
PCM connector terminals C5
and 820.Check tor a short in the wirc (ALt
F line):1. Turn the ignition switch OFF
2. Disconnect the negative bat_
tery cable from the baRery'
3. Disconnect the ECM/PCM con'
nector C (31P).
4. Check for continuity between
body ground and ECM/PCM
connector terminal C5
ls there aPProx. 5 V?
Check the operation otthe ALT:
1. Turn the ignition switch OFF.
2- Reconnect the ALT 4P (3P)*
connector to the ALT
3. Start the engine. Hold the
engine at 3,000 rpm wrth no
load {in Park or neutrali until
the radiator fan comes on,
then let it idle.
4- Measure voltage between ECM/
PCM connector terminals C5
and 820.
Repair short in the wire between
the EcM/PCM {C5l and the ALT.
Substitute a known-good ECM/
PCM and rechock. lf P.esc.ibedvoltage is now availabl€, ieplace
tho original ECM/PCM
Does the voltage decrease when
headlights and rear delogger are
turned on?
ALT FF signal is OK.
Repair oPen wire betwoen t|lo
ECM,/PCM {C5) and the ALT.
ALT F (WHT/RED)
Wire side of temale terminals
*: Canada model
Wire side of female termrnals

ldle Control System
Brake Switch Signal ('96 - 98 Models, '99 - 00 Dl6YS engine with M/Tl
This signals the ECM/PCM when the brake pedal is deoressed.
LGlBKSW(GRN/WHTI
D {16P)
Wire side of female t€rminals
Inspection of Brake Switch Signal.
Are the brake lights on withoutdepressing the brake pedal?
Depress the brake pedal.
Inspect the HORN (15 A) fuse inthe under-hood fuse/ relay box.Do the brake lights come on?
- Repair short in the wirebetween the brake 3whch andrhe HORN 115 At lu3e.- Replace the I|oRN 17.5 A) tus€.
Repair open in the wirebetween the brake switch andthe HORN 115 Al fuse.Inspect th6 br.ke switch {s6€section l9l.Check tor an open in the wireIBKSW line):1. Oepress the brake pedal.2. Measure voltage betweenECM/PCNI connector terminalsAg and D5 with the brake pedaloepresseo.
Repair open in the wire b€tweenthe ECM/PCM {Dsl and the brakeswitch.
ls there battery voltage?
Brakc switch sign.l is OK.
ECM/PCM CONNECTOFS
A (32PtIBRI\v
,la678101112I
121311151617t8192022232aI9101112
25212Aa3013141516
11-210

IJBrake Switch Signal ('99 - 00 Models except Dl6Y5 engine with M/Tl
This signals the ECM/PCM when the brake pedal is depressed
I
lnsoection ot Brake Switch signal.
Are the brake lights on without
depressing the brake Pedal?
Depress the brake Pedal
Inspect the HoRN {15 A} fuse in
the underhood fuse/ relay box'Do the brake lights come on?
- R.pair short in the wiro be'
tween the brake switch and
the HORN (15 Alfuse.- Replac€ the HORN (15 A) tuse.
- Repair open in the wite be'
tween the brako switch and
the HORN (15 Alfuse.- lnsoect the brake switch (3ec
section tgl.
Check fot an oPen in the wire
{BKsw linel:
1. Depress the brake Pedal.2. Measure vohage beween ECM/
PCM connector terminals A32
and 820 with the brake Pedaldepressed.
Bepair open in the wire between
the ECM/PCM (A32) and the
brake switch.
Brake switch signal i5 OK
ECM/PCM CONNECTORS
BKSW (GRN/WHTI
LG1 {BRN/BLK)
Wire side o{ female terminals

I
PCM CONNECTOR B {25P1 {cont'dl
Terminal NumberSignalDescriptionMeasuring Conditions/Terminal Vohage
811SHBShift control solenoid valve B
control
In 1st gear and 2nd gear in -q1, q11 position,
and in E] position: Battery voltage
In 3rd gear and 4th gear in lD.J, [Dr- position: 0 V
B't2SLUInterlock controlWhen ignition switch is ON (ll), brake pedal
deoressed and accelerator Dedal released: 0 V
813D4 INDD4 Indicator light controlWhen ignition switch is first turned ON (ll):
Battery voltage for two seconds
In E position: Baftery voltage
B't 4NMSGMainshaft speed sensor groundAlways: 0 V
E tcNMMainshaft speed sensor signal
input
Depending on engine speed: Pulsing signal
When engine is stopped: 0 V
816ATP RAy'T gear position switch Eposition signal input
InE position: 0V
In other than E position: Battery voltage
817ATP 2A/T gear position switch E posi-
tion signal input
InE position: 0V
In orher than E position: Battery voltage
818 to 821Not used
s22NCSGCountershatt speed sensor groundAlwaysr 0 V
B23NCCountershaft speed sensor signal
input
Depending on vehicle speed: Pulsing signal
When vehicle is stopped: 0 V
B24ATP D4Ay'T gear position switch lor posi-
tion signal input
InEposition:0V
In other than 6 position: 5 V
ATP NPA,/T gear position switch E and
N position signals input
InE and E positions: 0V
In otherthan E and N] positions: Battery voltage
PCM CONNECTOR C {31P)
Terminal NumberSignalDescriptionMeasuring Conditions/Terminal Voltage
Cl to C6- see section 11 -
c1Service check signalWith ignition switch ON (ll) and service check
connector oDen; 5 V
With ignition switch ON (ll) and service check
connector connected with sDecial tool: 0 V
C8 to Cg- see section 11 -
c10VBUBack-up power systemAlways battery voltage
C11 to C31- see section '11 -
PCM CONNECTOR D (16P}
Terminal NumberSignalDescriptionMeasuring Conditions/Terminal Voltage
Dl to D4- see section 11 -
D5STOP SWBrake switch signal inputBrake pedal depressed: Battery voltage
Brake pedal released: 0 V
D6 to D16- see section 1 l -
14-43

PCM Terminal Voltage/Measuring Conditions ('99 - 00 Models)
A/T Control System
The PCM terminal voltage and measuring condjtions are shown for the connector terminals that are related to the A//T con-trol system, The other PCM terminal voltage and measuring conditions are described in section ,11.
PCM Connoctor Tgrminrl Locations
PCM CONNECTOR A {32PI
PCM CONNECTOR 8 (25P}
Terminal NumbelSignalDescriptionM€asuring Conditions/Terminal Voltage
A105L5Service check signalWith ignition switch ON (ll) and service check
connector open: Approx, 5 V
With ignition switch ON (ll) and service check
connector connected with sDecial tool: 0 V
A14D4 INDE indicator light controlWhen ignition switch is first turned ON (ll):
ApDrox. 10 V for two seconds
In E position: Approx. 1O V
428ILUInterlock ControlWhen ignition switch ON (ll), brake pedal
depressed, and accelerator pedal rereaseo:
Battery voltage
A.32STOP SWBrake switch signal inputBrake pedal depressed: battery voltage
Brake oedal released:0 V
Terminal NumberSignalDescdptionMeasuring Condhions/Torminal Voltag6
B1!GP1Power supply systemWith ignition switch ON (ll): Battery voltage
With ignition switch OFF: 0 V
PGlGround
B8LS AMLinear solenoid power supply
negative electrode
With ignition switch ON (ll): Pulsing signal
B9IG P2Power supply systemWith ignition switch ON (ll): Baftery voltage
With ignition switch OFF: 0 V
810PG2G rou nd
917LS APLinear solenoid power supplypositive electrode
With ignition switch ON (ll): Pulsing signal
B20Ground
VBUBack-up power supplyAlways battery voltage
822Ground
\
14-46

Troubleshooting Flowchart - Brake Switch Signal
Symptom
Shift lever cannol b€ moved f.om
B pGition with the brako podrl
depr8sed.
PCM CONNECTORS
Check Brako Light Operation:Deoress the brake pedal.
Rop.ir faulty braks switch cilcuit
lsos soction 231.Are the brake lights ON?
Measure SToP SW Vohag€:1. Turn the ignition switch OFF.2. Disconnect the A l32P) and D
{l6P) connectors from thoPCM.3. Measure the voltage belweenthe D5 and A9 or A22 termi-nals with the brake Pedaldepressod.
Rap.i. opon in the wira bctn oentha 05 terminal and tho btrkclwitdr.ls there battery voltage?
. Brake switch 3ign.l is OK.. Ch6ck lor looao PCM oonnoctors.It nocassary, aubctilute a known-good PCM and r€check.. Inspoct the brake switch circuit
{s6e section 231.
Wire side of lemale terminals

ElectricalTroubleshooting ('99 - 00 Modelsl
Troubleshooting Flowchart - Brake Switch Signal
PCM CONNECTORS
Wire side of female terminals
Shift lever cannot be moved tromE position with tho b.ake pedaldepressod.
Check Brake Light Operation:Depress the brake pedal.
Repair t ulty brake switch circuit{see s€ction 23}.Are the brake llghts ON?
Mea3ure STOP SW Vohage:1. Turn the ignition switch OFF.2. Disconnect the A (32P) and B{25P} connectors from thePCM,3. Measure the voltage betweenthe A32 and 820 or 822 termi-nals with the brake pedal
depressed.
Repair open in the wire betwsenthe A32 terminal rnd tho brrk6switch.
ls there battery voltage?
. Brak€ switch sign.l is OK.. Check for loose terminal fil inlhe PCM conn€ctors. lf neces-sary. substitute a known-goodPICM and recheck.. InsDect the breke 3witch circuitlsee section 231.
B {25P)
\
14-104

TCM Terminal Voltage/Measuring Gonditions
('96 - 98 Modelsl
TCM Terminal Loc.tions
TCM-A l25P) Connecto.
TCM CONNECTOR A (26P}
TCM-B (22P) Connectot
2418910111213
1115161720232526
Terminal NumbetSignalDsscriptionMoasuring Conditions/Torminsl Vohrgo
A1SC LS_Stan clutch control linear solenoidpower supply negative electrodeEngine idling, E position:Approx. 0.4 VHLC LS-PH-PL control linear solenoid Dowersupply negative electrodeEngine idling, E position:Approx. 0.7 V
Shift control linear solenoid oowersupply negative electrodeEngine idling, E position:Approx. 0.8 V
A4LG1Ground
NEEngine speed signal inputWith engine running: Pulsing signalA6Not used
A7ATP LA/f gear position switch El positionsignal inputInEposition:OVIn other than El position: Approx. 1O VA8ATP Sly'T gear position switch E positionsignal inputIn lg position: 0 VIn other than E position: Approx. 10 VA9ATP DA{/T gear position switch E positionsignal inputIn lll position: 0 VIn other than E position: Approx. 10 VAr0ATP NPA,/T gear position switch E or Eposition signals inputInEorEposition:oVIn otherthan E orE position: Approx. 1O VA11ATP RA,/T gear position switch E positionsignal inputIn lE position: 0 VIn other than E position: Approx. 1O VA.12tGlPower supply systemWith ignition switch ON (ll): Banery voltsgeWith ignition switch OFF: 0 VA13PG1Ground
414Start clutch control linea. solenoidpower supply positive electrodeEngine idling, E position:Approx. 2.5 VA15HLC LS+PH-PL control line8|. solenoid powersupply positive electrodeEngine idling, El position:Approx. 5.0 VA16SH LS+Shift control linear solonoid oowersupply positive electrodeEngine idling, E position:Approx. 6.0 V417Ground
A18Not used
A19Not used
420D INDE indicator light controlWhen l9l indicator light comes on: Approx. jO VWhen lll indicator lighr OFF: 0 VA2'lNot used
422Not used
VBUBack-up power systemAlways battery voltage424Not used
A.25tG1Power supply systemWith ignition switch ON (lt): Baftery voltageWith ignition switch OFF:0 VPG1Ground
L
14-228