Jeep 1987 Wrangler Workshop Manual page 1747

DESCRIPTION
Battery feed for this circuit originates at the lighting
fuse link located at the starter relay/solenoid. Once
inside the passenger compartment, the wire is spliced to
feed the PARK/TAIL fuse, headlamp switch and fog
lamp relay. Circuit protection is provided by the fuse
link, PARK/TAIL fuse and a 25 amp circuit breaker
located in the headlamp switch.
The dimmer switch transfers battery feed from the
headlamp low beam filament to the high beam filament.
It also serves as a fog lamp lock-out circuit. The circuit
to the fog lamp switch is completed only when the dim-
mer switch is in the low beam position.
In the ON position, the fog lamp switch completes the
relay coil battery feed circuit. With the coil energized,
FOG LAMPS
TROUBLESHOOTING — O n e Lamp Out
From the headlamp switch, the circuits branch into the relay contacts close connecting the fog lamps to bat-
the tail/sidemarker/park lamp circuits and the head- tery feed through splice A and the lighting fuse link,
lamp circuit. Before reaching the headlamps, battery
1. LAMP
feed is routed to the dimmer switch, where it branches
into the head/indicator/fog lamp circuits.
T E S T O K
NOT OK
Across bulb terminals Zero ohms Replace bulb
TAIL/SIDEMARKER/PARK LAMPS
Battery side of lamp
connector
12 volts Repair open to battery side of wiring
connector
TAIL/SIDEMARKER/PARK LAMPS
TROUBLESHOOTING—One Lamp Out
Ground side of lamp
connector to clean chassis
ground
Zero ohms Repair open to G305/306
1. LAMP: Headlamp switch ON
T E S T
OK NOT OK
Install replacement bulb Lamp on Next test
Battery side of bulb
socket 12 volts Repair open to battery side of bulb-socket
Ground side of bulb
socket
Zero ohms Repair open in ground wire
2. FUSE: Battery feed from splice A
T E S T O K N O T O K
Inspect park/tail fuse Not blown Replace fuse
Battery side of park/tail
fuse
12 volts Repair open from fuse link J/2.5L, A/4.2L
(splice A)
3. HEADLAMP SWITCH: Headlamp switch ON
TEST OK
N O T O K
Terminal E 12 volts Repair open from fuse panel
Terminal A 12 volts Replace switch
TROUBLESHOOTING — B o t h Lamps Out
1. SWITCH/INDICATOR LAMP: Headlamp switch ON; dimmer switch
in LO; fog lamp switch ON
TEST
OK NOT OK
Terminal B 12 volts Repair open from dimmer switch
Terminal C 12 volts Replace switch
Terminal A Zero volts
Zero volts and indicator lamp off—replace
switch
12 volts—repair open to ground G305/306
3. RELAY
TEST
OK NOT OK
Terminal 30 12 volts Repair open in wire from Splice A (Fusehnk
J/2.5L, A4.2L
Terminal 86 12 volts Repair open from fog lamp switch
Terminal 85 Zero volts Repair open to G305/306
Terminal 87 12 volts Replace relay
Tail/Sidemarker/Park Lamps 47
Fog Lamps 47