transmission NISSAN 300ZX 1984 Z31 Engine Fuel And Emission Control System Workshop Manual

Page 16 of 79

E.C.C.S. DESCRIPTION
E. C. C. S. Corn1
In order to ensure the stable performance of the
exhaust
gas sensor, a ceramic heater is employed
inside the zirconia tube
,-Ceramic zirmnia tube
.- . .. . ... .. . . . . . .. .. --_
SEF622B
THROTTLE VALVE SWlTCl
The throttle valve switch is attached to the throttle
chamber and actuates in response
to accelerator
pedal movement
This switch has idle contact and full throttle con-
tact The idle contact closes when the throttle
valve
is positioned at idle and opens when it is at
any other position.
The full throttle contact
is used only for the
electronic controlled automatic transmission
SEF623B
Full throttle contact p0,nt
nents (Cont'd)
VEHICLE SPEED SENSOR
(VG30ET
engine only)
The vehicle speed sensor provides a vehicle speed
signal
to the E C.C S. control unit
Needle type speedometer models
The speed sensor consists of
a reed switch, which IS
installed in the speed meter unit and transforms
vehicle
speed into a pulse signal.
Magnetic line
\# Reed \I
i : !' sw17CI i N S"
Field 0 plate Field plate
SEF624B
Digital type speedometer models
The speed sensor consists of
an L E D , photo
diode, shutter and wave forming circuit.
Its princi-
ple
is the same as that of the crank angle sensor
011 seal
0 To speedometer cable
SEFS80B
EF & EC-16

Page 47 of 79

ELECTRONIC CONTROL SYSTEM INSPECTION
:@ Vehicle speed sensor (Code No. 14)
Disconnect speedometer cable from transmission
I
SEF678B
I
Disconnect 16-pin connector from E C C S control
unit and check continuity between terminal
@
and ground while slowly turning speedometer cable
ONIOFF puk should be detected n
(Refer to “METER AND GAUGES in
Replace E C C S control unit
EF & EC-4‘7