One Lamp Inoperative Or Intermittent; Both Lamas Inoperative Or Intermittent; Lamps Will Not Turn Off; Stop Lamps - Pontiac TRANS AM 1977 Service Manual

CHASSIS ELECTRICAL 8-69
BACK-UP LAMPS
One Lamp Inoperative or Intermittent
CAUSE CORRECTION
Open ground connection.
Loose connection.
Bulb out.
Repair bulb ground circuit.
Tighten connectors.
Replace bulb.
Both Lamas lnooerative or Intermittent
CAUSE CORRECTION
Fuse blown.
Loose connection or open circuit.
Neutral-safety swtich misadjusted (open
when shift lever is in reverse position).
Defective neutral-safety swtich.
Defective Ignition Switch
Replace fuse. If new fuse blows, repair short
to ground in circuit from fuse through
neutral-safety switch to back-up lamps.
Secure all connectors. If OK,
check continuity by voltage checking
circuit from fuse to lamps with test bulb.
If test bulb does not light on either side of
fuse, check open circuit from battery to fuse.
Adjust
With ignition on, check voltage at terminals
with switch in back-up position. If bulb lights
at pink wire terminal but not at output
terminal, replace ignition switch.
If test bulb lights at ignition switch
battery terminal but not
at
output terminal,
replace ignition switch.
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Lamps Will Not Turn Off
CAUSE CORRECTION
Neutral-safety switch misadjusted
(closed when shift lever is not in reverse
position).
Adjust.
STOP LAMPS
One Bulb lno~erative
One Side Inoperative
CAUSE CORRECTION
Loose connection, open wiring or defective Turn on directional signal. If lamp does
bulbs. not operate, check bulbs. If bulbs are
OK, secure all connections. If lamp still
does not operate, check for open wiring with
a test bulb.
Defective directional signal switch If lamp will operate by tuming on directional
or cancelling cam.
signal, the switch is not centering
properly during cancelling operation.