Cadillac 60 Series 1963 Shop Manual page 369

12-;
ELECTRICAL SYSTEM
2. Disconnect, three-way electrical plug from
power relay unit.
3. Remove ground wire from screw on dash
insulator.
4. Remove two screws holding power relay unit
to dash insulator and remove unit.
b. Installation
1. Position power relay unit against dash in-
sulator and secure with two screws.
2. Install ground wire under screw on dash
insulator.
3. Attach two-way electrical plug to power
relay unit.
4. Connect three-way electrical plug to power
relay unit.
113. Minor Service Corrections
1. Check car battery voltage. It must be at
least 11 volts for unit to function.
2. Check to see that all external connections
are tight and properly made. Make certain that
power relay unit is grounded under dash insulator
mounting screw.
3. Check condition of 4 amp fuse and, if neces-
sary, replace. If fuse blows again, inspect wiring
for external short.
4. Isolate the i n o p e r a t i v e component. See
Note 114.
5. If amplifier is inoperative:
a. Remove amplifier unit from mounting.
b. Ground amplifier to car body by means of a
jumper wire.
c. Turn on headlights and, after 30 seconds
warm-up time, inspect for filament glow in ballast
tube and amplifier tube. The ballast tube may or
may not glow, but should get hot.
d. Replace apparently defective tube or tubes,
with a replacement tube known to be good. See
Note 109.
e. Disassemble amplifier unit and inspect all
electrical connections, Note 108. When soldering,
use only resin core solder.
If the above procedure fails to correct the
trouble, the amplifier will have to be sent to an
authorized service facility for servicing. See
Note 108.
6. If phototube is i n o p e r a t i v e , proceed as
follows:
a. Replace tube assembly. See Note 111.
b. Inspect a l l electrical connections. When
soldering, use only rosin core solder.
If this procedure fails to correct the trouble,
phototube unit and amplifier unit will have to be
sent to an a u t h o r i z e d service facility. See
Notes 107 and 110.
7. If foot switch is inoperative it must be
replaced.
8. If power relay unit is inoperative, it must
be replaced.
The Guide-Matic electrical circuit diagram,
Fig. 12-106, is provided to assist in correcting
any wiring problems that may be encountered.
114. Diagnosis
a. Headlights Stay on Low Beam
1. Turn on headlights and let Guide - Matic
warm-up for at least one minute. Set driver con-
trol knob to detent position. Cover phototube unit
with a dark cloth.
a. If headlights switch to upper beam, system
is operating but requires sensitivity adjustment.
b. If headlights stay on lower beam, position
amplifier HOLD control in approximate center of
its travel. This will eliminate possibility of lock-
ing headlamps on low beam due to complete mis-
adjustment. If headlights remain on low beam
when phototube is again covered, proceed to
step 2,
2. Reaching t h r o u g h glove box, disconnect
phototube unit plug from socket on amplifier unit.
a. If headlights go to upper beam, trouble is in
phototube unit.
b. If headlights remain on lower beam, trouble
is in amplifier unit, power relay unit, or foot
switch. Proceed to step 3.
3. Make certain that power r e l a y unit is
grounded under dash insulator mounting screw.
Disconnect two-way amplifier plug from power
relay unit and connect a jumper wire across the
two exposed terminals.
a. If headlights remain in low beam, trouble is
in power relay unit.