2000 HONDA CIVIC Vehicle Speed Sensor

Electronic Control System ('96 - 98 Modelsl
The electronic control system consists of the Transmission control Module (TcM), sensors, three linear solenoids, and an
inhibitor solenoid. Shifting is electronically controlled under all conditions
The TCIM is located below the dashboard, behind the kick panel on the driver's side'
The TcN4 controls the transmission to reduce engine speed and retain the engine's cooling efficiency when the vehicle is
driven with Iull throttle acceleration
lf the vehicle is continuously driven at full throttle acceleration, the TCM regulates the pulley hydraulic pressure to
increase the pulley ratio, which, as the result. reduces the engine speed and retains the designed cooling efficiency After
the vehicle has been driven at a lower engine speed for a while, the TCM increases the pulley ratio to the original ratio.
For smooth starting in the E position, the TcM sends a signal to the EcM to cut off the rvc clutch {if the A!/c is on) and
increases the engine speed to 900 rpm when the transmission is shifted to the E position'
The start clutch functions to make smooth starting possible. To let the start clutch function properly. the TCM regulates
the start clutch hydraulic pressure based on the entine's negative pressure memorized in the E position'
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S*ond.ry G..r Sh:ft
(cont'd)
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Electronic Gontrol System ('99 - 00 Modelsl
The electronic controt system conststs of a Powertrain control Module (PCM). sensors, three linear solenoids and an
inhibitor solenoid. shifting is electronically controlled under all conditions A Grade Logic control system to control shift-
ing in E position while the vehicle is ascending or descending a slope'
fn"pCVirlocatedbelowthedashboard,underthekickpanelonthepassenger'sside'
The pCM controls the transmassion to reduce engine speed and retain the engine's cooling efficiency when the vehicle is
driven with full throftle acceleration
lf the vehicle is continuously driven at lull throttle acceleration, the PCM regulates the pulley hydraulic pressure to
increase the pulley ratio which. as the result, reduces the engine speed and retains the designed cooling efficiency After
the vehicle has been driven at a lower engine speed for a while, the PCM increases the pulley ratio to the original ratio'
i"i ".nl",rr starting in the E position, the PcM cuts off the ,Vc clutch (if the A/c is on) and increases the engine speed to
900 rpm when the transmission is shifted to the E position'
The start clutch functions to make smooth starting possible. To let the start clutch function properly, the PcM regulates
the start clutch hydraulic pressure based on the engine's negative pressure memorized in the E position'
FCM
s*o.d.ry G..t Sh.h
(cont'd)
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Description
Electronic Control System ('99 - 00 Modelsl (cont'dl
Grade Logic Control System
How it works:
The PcM compares actual driving conditions with memorized driving conditions. based on the input from the vehiclespeed sensor, the throttle position sensor, the manifold absolute pressure sensor, the engine coolant temperature sensor,the brake switch signal, and the shift lever position signal, to control shifting while the vehicle is ascending or descendinga slope.
Ascending Control
When the PCM determines that the vehicle is climbing a hill in E position, the system selects the most suitable shiftschedule (pulley ratio) according to the magnitude of a gradient. so the vehicle can run smooth and have more powerwhen needed. There are three ascending modes with different shift schedules according to the magnitude ot a gradient inthe PCM.
Descending Control
when the PCM determines that the vehicle is going down a hill in E position. the system selects the most suitable shiftschedule (pulley ratio) according to the magnitude of a gradient. This, in combinstion with engine braking, achievessmooth driving when the vehicle is descending, There are three descending modes with different shift schedules accord-ing to the magnitude of a gradient in the PCM.
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Component Locations
36 - 98 Models
BRAKE SWITCH
DRIVEN PULLEYSPEED SENSOR
INHIBITOR SOLENOID
ENGINE CONTROLMODULE IECMI
SECONDARY GEAR SHAFTSPEEO SENSOR
AUTOMATIC TRANSAXLE (A/T}GEAR POSITION SWITCI{
MANIFOLD ABSOLUTE
VEHICLE SPEEO SENSOR{vss}
IMAPI SENSOR
THROTTI.I POSITION {TPISENSOR
PH.PL CONTROLLINEAR SOLENOID
/i/ i,' / ,','4
,i/:1
t"--.---.- i,,
-_,-:-_a.--:
il
START CLUTCH CONTROLLINEAR SOLENOIDPULLEY
SHIFT CONTROLLINEAR SOLENOTD
$r,
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h
SPEED SENSOR

'99 - 00 Models
CONTROL
AUTOMATIC TRANSAXLE IA/TI
GEAR POS]TION SW]TCH
MANIFOLD ABSOLUTESECONDANY GEAR SHAFT
SPEED SENSORIMAPI SENSOR
VEHICLE SPEED SENSOR
tvss)
THROTTLE POS]TION ITP)SENSOR
PH.PL CONTBOLLINEAB SOLENOIO
DNVEN PUL]-EY
SPEED SENSOR
START CLUTCH CONTROL
PULLEY
SHIFT CONTROLLINEAR SOLENOIO
LINEAR SOIENOID
SPEED SENSOR
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TCM CONNECTOR B (22P}
Terminal NumbelSignalDescriptionMeasuring Conditions/Terminal Voltage
B1SOL INHInhibitor solenoid controlWith inhibitor solenoid ON: Baftery voltage
With inhibitor solenoid OFF: 0 V
82MAP (PB)-M an if old Absol r-rte Pressure IMAP)
sensor signal inPUtWith iqnition switch ON (ll): Approx.2.5 V
With e;gine adling: Approx. 1.0 V (depending on
engine speed)
B3Not used
B4TPS-Throttle Position (TP) sensor signal
input
With ignition switch ON (ll) and throftle fully open:
4.14 - 4.42 VWith ignition switch ON (ll) and throttle fully
closed: 0.44 - 0.56 V
VSSVehicle Speed Sensor (VSS) signal
Inpur
With ignition switch ON (ll) and rotating front
wheelsr 0-5Vcycle
TMBData communication with ECM:
Transmission control data outpUt
With ignilion swltch UN lll): rulslng slgnar
81TMAData communication with EClvl:
PGM Fl control data inPut
With ignition swltch uN {ll,: l-ulslng slgnal
B8NDN SGDriven pulley speed sensor ground
B9NDNDriven pulley speed sensor signal
input
ln other thTnE and E position: Pulsing signal
810NDRDrive pulley speed sensor signal
Input
-tn ottrer ttran E ana E position: Pulsing signal
811Not used
812STOP SWBrake switch signal inPutWith brake pedal depressed: Battery voltage
With brake pedal released: 0 V
813DIAG-H(TXD/RXD)Data communication:Diagnostic trouble code outPut
Wittr ignitio.r s*itct' ON (ll): Approx 5.0 V
814Se-ice ctrect signatWith ignition switch ON (ll) and service check
connector oPen: APProx.5 V
With iqnition switch ON (ll) and service check
"onn"itot. connect"d with special tool: 0 V
Secondary gear shaft speed sensor
signal input
Depending on vehicle speed: Pulsing signal
When vehicle is stoPped: 0 V815VEL
816VEL SGSecondary gear shaft speed sensorgrouno
817NDR SGDrive pulley speed sensor ground
818HBRK SWParking brake switch signal inPutWith parking brake lever pulledr 0 V
With parking brake lever released: Battery voltage
819Not used
B20VREF+5 V relerenceWith ignition switch ON (ll): Approx 5 V
821Not used
Not used

\a
PCM CONNECTOR D {16P)
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Terminal Numbs]SignalDescriptionMeasuring Conditions/Terminal Voltage
D1VELSecondary gear shaft speed
sensor signal input
Depending on vehicle speed: Pulsing signal
When vehicle is stoPPed: APProx. 0 V
02SOL INHlnhibitor solenoid controlWith inhibitor solenoid ON: Battery voltage
With inhibitor solenoid OFF: 0 V
D3SH LSMShift control linear solenoid
power supply negative electrode
D4SH LSPShift control linear solenoid
power supply positive electrode
With ignition switch ON (ll): Pulsing signal
D5VB SOLPower supply for solenoid valvesWith ignition switch ON (ll): Baftery voltage
With ignition switch OFF:0 V
D6ATP RA,/T gear position switch E
position input
InEposition:0V
In other than B position; Approx. 10 V
D]VEL SGSecondary gear shaft sPeed
sensor ground
D8Not used
D9Not used
D10NDNDriven pulley speed sensor signal
anput
In other than E and E position: Pulsing signal
D11NDRDriven pulley speed sensor signal
input
ln other than E and E position: Pulsing signal
D12NDR SGDrive pulley speed sensor ground
D13ATP SA,/T gear position switch E
position input
InE position: 0V
In other than E position: Battery voltage
D14D INDD indicator light controlWhen ignition switch is first turned ON (ll):
Battery voltage for two seconds
In E position: Battery voltage
D15Not used
D16NDN SGDriven pulley speed sensor
grou nd

Symptom-to-Component Chart
Electrical System -'96 - 98 Models
*: The DTC in parentheses is the code @ indicator light indicates when the Data Link Connector is connected to the HondaPGM Tester.
DTC*O Indicator
LightMILDetection ltemPage
P1790
(3)BlinksONThrottle position sensor14-242
P179'l
(4)BlinksONVehicle speed sensor14-243
P1705
(5)BlinksONAy'T gear position switch (short to groundl't 4-244
P1706
(6)OFFONA/T gear position switch {open)14-246
P0725
(11)BlinksONlgnition coil14-248
P1793
112lBlinksONManifold absolute pressure sensor14-249
P 1870(30)BlinksONShift control linear solenoid14-250
P'1873
(311BlinksONPH-PL control linear solenoid14-25'l
P1879(32)BlinksONStart clutch control linear sotenoid14-252
P1882BlinksONInhibitor solenoid14-253
P1885
(34)BlinksONDrive pulley speed sensor1l-Zb4
P1886(35)BlinksONDriven pulley speed sensor14-255
P1888
(36)BlinksONSecondary gear shaft speed sensor14-256
T to55
(37)BlinksONECM or TCM14-257
P1890
l42lBlinksONShift control system14-259
P1891
(43)BlinksONStart clutch control svstem14-260
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