The indicators work OK but the headlight, rear light & horn don't.

#1: Panel Illumination
#2: Guages,Right High beam headlight and the high beam indicator
#3: Rear Wiper, Left headlight High Beam
#4: RH park, backup lights switch and relay,Speed porpotional steering module,power door lock switch illumination and daytime running lights(Canada)
#5: Power Door locks,Power Mirrors,vanity,dome,map,ignition and trunk lights,sunroof,radio,power antenna,body control module and power for the data link connector
#6:Heated mirrors,heated rear window indicator
#7: Instrument cluster illumination,park and tail lights
#8: Cigarette lighter,Radio Amp and horns
#9: Power door lock motors
#10: Not used
#11: Radio
#12:Left low beam head light
#13,14,15,16 not used

CHECK VOLTAGE USING VOLT METER EITHER NOT ENOUGH POWER ALTERNATOR STATOR MAGNITO BATTERY ETC OR FAULTY WIRE ETC.

My first guess would be a ground problem.
The headlights and tail lights are controlled by the same headlight switch, but the brake lights are on a totally different circuit.
You may have to get a shop manual to get the wiring diagrams needed to troubleshoot the circuits if the ground connections are ok.
The lights involve the body computer and other components.

intermintant loss of power to headlights clock air conditioning 2001 toyota avalon ! solution....new alternator and new battery fitted.

Left side dashboard facing the door. Remove the oblong panel.

The fuse panel diagram is in your owners manual, if you don't have one, go to Jeep.com and download it for free.

Fuse Panel Description
Cavity Fuse Description

• 1 15 Amp Blue Horn Relay, Power Sunroof Relay, Power Window Relay
  

• 2 10 Amp Red Rear Fog Lights (Export Only)
  

• 3 20 Amp Yellow Cigar Lighter
  

• 4 10 Amp Red Headlight Low Beam Right

• 5 10 Amp Red Headlight Low Beam Left

• 6 20 Amp Yellow Body Control Module/Power Door Locks
  

• 7 10 Amp Red Left Park Light/Left Tail Lamp/License Plate Lamp
  

• 8 Spare

• 9 10 Amp Red Right Park Light/RightTail Lamp/License Plate Lamp/ Cluster
  

• 10 Spare

• 11 15 Amp Blue Flasher

• 12 15 Amp Blue Stop Lights

• 13 10 Amp Red Body Control Module/ CMTC/Cluster/Pass. Airbag On,Off Indicator, Auto Daylight Mirror/Light Bar Switch (Renegade Only)
  

• 14 10 Amp Red PDC Fuel Pump/AC Clutch, Starter Relay/Engine Controller/Transmission Controller (Diesel Only)
  

• 15 Spare

• 16 20 Amp Yellow Power Outlet (Rear)
  

• 17 15 Amp Blue Rear Wiper

No there not connected, replace the brake light
1999 Chevrolet Blazer Auto Light Bulb Size Guide
Low Beam Headlight Bulb Size: 9006
High Beam Headlamp Light Bulb Size: 9005
Parking Light Bulb Size: 3157
Front Turn Signal Light Bulb Size: 3157
Rear Turn Signal Light Bulb Size: 3057
Tail Light Bulb Size: 3057
Stop Light Bulb Size: 3057
High Mount Stop Light Bulb Size: Assembly
Fog/Driving Light Bulb Size: 880 or 881
License Plate Light Bulb Size: 194
Back Up Light Bulb Size: 3156
Front Sidemarker Light Bulb Size: 194
Ash Tray Light Bulb Size: 161
Glove Box Light Bulb Size: 194
Map Light Bulb Size: 168 or 211-2
Step/Courtesy Light Bulb Size: 168 or 211-2
Trunk/Cargo Area Light Bulb Size: 211-2
Under Hood Light Bulb Size: 93
Instrument-General Light Bulb Size: 161 or 37 or PC194 or PC74
Check Engine Indicator Light Bulb Size: PC74
Hi-Beam Indicator Light Bulb Size: PC74
Seat Belt Indicator Light Bulb Size: PC194
Brake Warning Light Bulb Size: PC74
Automatic Transmission Indicator Light Bulb Size: 194
Directional Signal Indicator Light Bulb Size: PC74
As for the horn, inspect the fuse and relay and most common it would be a bad ground wire or worst a bad horn due to corrosion. Horn will be located in the drivers side fender.
Thank you for using fixya.

Check your fuse then try again. Do not forget to check your main fuse- the ribbon type (30Amp)

have a look in the headlight as all the wiring is usually at the back there , you could have a loose connection .
Just unscrew the headlight and have a look through all the wires and make sure all connections are ok .

replace all the fuses and bulbs

Fuse #8, #18 and #22.

Below is a listing of which fuse corresponds with which circuit:

1 - 10 Amp - Transmission Controller, Gauges, Autostick
2 - 10 Amp - Right High Beam Headlight
3 - 10 Amp - Left High Beam Headlight
4 - 10 Amp - Radio, CD Player
5 - 10 Amp - Washer Motor
6 - 15 Amp - Power Outlet
7 - 20 Amp - Tail, License, Parking, Illumination Lights, Instrument Cluster
8 - 10 Amp - Airbag
9 - 10 Amp - Turn Signal Lights, Turn Signal/Hazard Indicator
10 - 15 Amp - Right Low Beam
11 - 20 Amp - High Beam Relay, High Beam Indicator, High Beam Switch
12 - 15 Amp - Left Low Beam Headlight
13 - 10 Amp - Fuel Pump Relay, Power Train Control Module
14 - 10 Amp - Cluster, Day/Night Mirror,Sunroof, Overhead Console, Garage Door Opener, Body Control Module
15 - 10 Amp - Daytime Running Light Module (Canada)
16 - 20 Amp - Fog Light Indicator
17 - 10 Amp - ABS Control, Back Up Lights, Daytime Running Lights, A/C Heater Control Cavity Fuse Circuits
18 - 20 Amp - Power Amplifier, Horn
19 - 15 Amp - Overhead Console, Garage Door Opener, Trunk, Overhead, Rear Reading, and Visor Vanity Lights, Trunk Release Solenoid, Power Mirrors, Power Door Locks, Body Control Module, Aspirator Motor
20 - 20 Amp - Brake Lights
21 - 10 Amp - Leak Detection Pump, Low Rad Relay, High Rad Relay, A/C Clutch Relay
22 - 10 Amp - Airbag
23 - 30 Amp - Blower Motor, ATC Power Module
24 - 20 Amp - Power Window Motors
25 - 20 Amp - Power Door Lock Motors, Power Seats