1808
GUIDE-MATIC HEADLIGHT DIMMER
G.M. GUIDE-MATIC
HEADLIGHT DIMMER (C nt.)
beam should go on by depressing foot switch %". If not,
see "No Overriding Upper Beam" below.
Unabl T Obtain Upp r B am: With "Hold" control in
center of rotation and upper beam obtained, adjustment
is necessary (see below), if no upper beam obtained,
disconnect phototube from amplifier. If upper beam goes
on, phototube is faulty. If upper beam does not go on,
disconnect foot switch wiring from switch and connect
car wiring, from amplifier to switch. Operate foot switch.
If lamps change beams, amplifier is faulty. If lamps
do n t change beams, foot switch or car wiring is faulty.
OLDSMOBILE
-ONLY
EXCEPT
L>
^OLDSMOBILE
BEAM
SELECTOR
SWITCH
BLUE-f
• T O HIGH BEAMS
• T O LOW BEAMS
PHOTOTUBE
Unabl T Obtain Lower Beam: Ground white wire between
phototube and amplifier (remove phototube cover for
access). If beams change, phototube is faulty. If beams
d n t change, remove red wire from switch. If beams
change, foot switch is faulty. If beams do not change,
remove foot switch wiring and connect car wiring from
amplifier t o switch. Operate switch. If beams change,
amplifier is faulty. If beams do not change car wiring
is faulty.
N
Ov rriding Upper B am: Ground red wire from foot
switch. If override obtained, foot switch is faulty. If
override n t obtained, amplifier is faulty.
TESTING & ADJUSTING: NOTE - Use Guide-Matic Tool
J-8465 (Buick. CadUlac, Pontiac); Level J-8465-20,
Test Lamp & Adapter J-8662 and Tester AE-2 (Oldsmobile) for installing, testing, and adjusting GuideMatic headlight dimmer.
Vertical Aiming Adjustment: CAUTION - Unit must be
aim d as low as p ssible to provide tolerance for car
I ading. Aim unit with car unloaded, trunk empty except
for spar tir , gas tank at least half-full and with tires
at c rrect pressure.
1) Locate car on level floor (1/4" fore and aft of car).
2) Rock car sideways to equalize springs. On Cadillac
with Air Suspension, idle engine to insure car levelness.
3) Set Aiming Device on Phototube Unit. NOTE - Three
points on Aiming Device must rest on top of Phototube
Unit and Aiming Device must be touching front of
Phototube Unit.
4) Note number stamped on Drive Control knob then
adjust aiming dial until corresponding number is under
pointer.
5) Adjust vertical aiming screw on Phototube Unit
until bubble i s centered in level.
Dim and Held Sensitivity T st: CAUTION - Cover Ph rctube Unit with black cloth. T sts or adjustm nts should
be made with Ph totube unit below 100°F. If car has
be n in th sun, place it in cool spot for appr ximately
on h ur b fore check is mad .
"GUIDE-MATIC" HEADLIGHT DIMMER WIRING DIAGRAM (TYPICAL)
1) Set Driver Control to "detent" position and install
tester lamp. Start engine and operate at fast idle while
making adjustments.
are located on side of Amplifier Unit (slotted for screwdriver adjustment). For access, remove plug from door
hinge pillar.
2) Turn headlights "ON" and wait five minutes for
Amplifier Unit to stabilize. Turn Zero corrector on
face of meter until meter pointer is on zero set line then
connect battery leads of tester unit to cigar lighter
receptacle (Oldsmobile), to battery terminals (Others).
2) For Hold Sensitivity, rotate Amplifier Hold Control
completely clockwise. Rotate tester Intensity Control
Control all the way clockwise. Turn Selector (DimHold Switch) momentarily to "DIM" position to switch
lights to lower beam, then switch back to "HOLD"
position.
NOTE - If lights do not switch to lower beam, the
amplifier Dim Control must be turned completely clockwise and then readjusted after "HOLD" adjustment is
correct.
3) For Dim Sensitivity, rotate tester Intensity Control
completely counterclockwise. Turn Selector on DimHold Switch to "HOLD" position and then back to
"DIM" position. Headlamps should be on upper beam.
4) Turn test Intensity Control clockwise slowly just
to point where headlamps switch to lower beam. Meter
pointer should now read in Black Sensitivity Range
on meter scale. If not proceed to "HOLD" Sensitivity
Adjustment, under Hold and Dim Sensitivity below.
5) For Hold Sensitivity, turn Intensity Control all the
way clockwise. Turn selector or Dim-Hold Switch, to
"DIM" position and back to "HOLD" position to obtain a lower beam.
6) Slowly turn Intensity Control counterclockwise just
to point where headlamps switch to upper beam. Meter
pointer should now read in the Green "HOLD" Sensitivity range on meter scale. If not, proceed to "Hold"
Sensitivity Adjustment under Hold and Dim Sensitivity below.
Hold and Dim Sensitivity Adjustment: CAUTION"HOLD'
Sensitivity
must be made properly before adjusting
"DIM" Sensitivity.
Phototube unit must be covered with
a black c/ th during adjustm nts.
1) Complete Steps 1 and 2 under Din and Hold Sensitivity Test. NOTE • Dim and Hold Sensitivity Controls
3) Adjust Intensity Control on tester slowly counterclockwise until meter pointer is on HOLD SENSITIVITY
adjustment line. Turn Amplifier Hold Control slowly
counterclockwise just to point where headlamps switch
to upper beam. Do not go beyond this setting. Recheck
Sensitivity, Steps 5 and 6 under Dim and Hold Sensitivity tests, above.
NOTE - Dim Sensitivity should not be adjusted until
"HOLD" Sensitivity is properly adjusted.
4) For Dim Sensitivity, rotate Amplifier "DIM" Control
completely counterclockwise. Momentarily turn DimHold Switch on tester to "HOLD" then back to "DIM"
position to obtain upper beam.
5) Adjust tester Intensity Control until meter pointer
is at Dim Sensitivity Adjustment Line then slowly
rotate Amplifier Dim Control clockwise just to point
where headlamps switch to lower beam. DO NOT go
beyond this setting.
6) Recheck Sensitivity, Steps 3 through 6 under Dim
Sensitivity, above. If Sensitivity is not correct, repeat
repeat adjustment procedure. If correct, turn off headlights, disconnect tester, remove Tester lamp from
Phototube Unit and reinstall plug in door hinge pillar.