Advertisement
8-70
INSTRUMENTS
wire, faulty printed circuit board or a defective fuel
gauge. The instrument cluster should be removed for
further tests. See "Instrument Cluster."
Testing
Fuel
Gauge-Instrument
Cluster
Removed
Wigs.
3,4 und 5 )
Place the instrument cluster on a padded service
bench to protect the cluster finish.
The gauges in the instrument cluster can be tested
with a fully charged 12 volt battery and Gauge Tester
To prevent a possible error that might result in
burning out the gauges the following test procedures
should be closely followed.
CAUTION: A direct connection from a
12
volt bat-
tery to the gauges will burn them out. A short
cir-
cuit to the printed circuitry will burn it out.
(1) On Models AP-1 and AP-2 insulate the pins at
both sides of the ignition input pin of the printed cir-
cuit board. Connect a jumper wire to the voltage
limiter input terminal on Models AV-1, AV-2, AR-1 and
AR-2 or to the ignition input terminal of the fuel gauge
on Models AP-1 and AP-2. Connect the other end of the
jumper wire to the positive post
(+)
of a 12 volt test
battery.
(2) Connect a jumper wire from the negative
(-)
post of the battery to the instrument cluster base
(ground).
(3) Connect one lead from Tester Tool C-3826 to
the fuel gauge "S" terminal.
With the gauge tester in the
"L"
position, the fuel
gauge should show "E" or minus
3/32
inch.
NOTE: The minus tolerance provides a small fuel
reserve when the gauge is on "E" position.
With the gauge tester on
"M,"
the fuel gauge
should slowly advance to the
Y 2
position. With the
gauge tester on
"H"
the fuel gauge should show
"F"
plus or minus
inch.
If
the gauge does not perform
as above test for an open printed circuit board or re-
place the fuel gauge.
To01 '2-3826.
TO
BATTERY
POSITIVE
TO
BATTERY
NEGATIVE
(+)
P O S T -
(-)
POST
Fig. &-Testing
Fuel Gauge-
Models AR-I and AR-2
Fig. 5-resting
Fuel Gauge-
Models AP-1 and AP-2
TEMPERATURE INDICATING SYSTEM
(Fig. 6 )
The operation of the temperature indicating system
is identical in operation with the fuel system with
the exception of the method of varying the resistance
of the sending unit. In this system the resistance
varies in direct relation to the temperature of the
coolant.
Any change in the coolant temperature causes a
like change in the resistor incorporated in the engine
sending unit.
When the engine is cold the resistance of the disc
in the temperature sending unit is high and a low
temperature will be indicated.
As the engine temperature increases, the resistance
of the temperature sending unit disc starts to de-
crease. A resultant increase in the current flow will
occur cabsing the gauge pointer to indicate the in-
crease in engine temperature.
.
I
(FROM VOLTAGE LIMITER
O R F U E L GAUGE)
TEMPERATURE SENDING
/UNIT
(ON ENGINE)
, , , , , @
I I 1
T E M P E R A ~ R E GAUGE
(ON
DASH
PANEL)
64x419
Fig. 6-lemperafure
Indicating System
Hide quick links:
Advertisement
