Before resorting to purchasing new fog lights , you must find why the lights aren't working . The only reason you would replace the lights would be if they were corroded and no amount of repair would be of help. Understanding that your not very experienced in electrical shouldn't bar you from trying to diagnose the problem yourself. I'll try to explain some very simple and basic tests involving a test light or meter . Be advised that some advanced electrical necessitates a wiring diagram since you'll want to be sure the circuit isn't powered or feeding back to the body control module or powertrain control module . Circuits that do need to be handled with computer safe equipment . The safest way is to obtain a computer safe test light . That way , you'll be assured that any circuit you check will be drawing only a minimal draw and will not cause an over draw causing damage to a circuit and/or the BCM or PCM . I don't wish to intimidate or even scare you from performing this diagnostics yourself but only want to advise you of the proper way and not cause any harm to your vehicle. Fore warned is fore armed .
The computer safe test light only draws about a quarter of a volt to power its diode type light bulb just as led lights do and don't tax the electrical system as some higher amperage lights do. A good multimeter that is computer safe with a ten mega ohm impediance rating is safe for this work but I don't think you'll need such an advanced / expensive meter to diagnose this problem . But at the same time , I wouldn't want you to get one of those cheap/ free multimeters such as harbor freight sells and put your jeep at risk and add to the problem . You would be surprised how many times someone starts out simple such as a light problem and "spiked" a computer circuit . I too once caused such an overdraw on a computer circuit because I didn't use a computer safe test light . the good thing about these test lights is that they can differentiate between positive and negative polarity just as a good multimeter can to let you know that you've made an incorrect connection and mistaken a loaded circuit for a ground. That is why it's best to use a computer safe test light. To check a loaded circuit ( one that is live) , attach the lead ( usually an alligator clip) to a ground and probe ( touch ) the suspected wire or terminal that carries power. If you were sure you know which wire or terminal is the live side and which is the ground ( via a wiring diagram ) , you use the alligator terminal on a body ground to check for a live circuit . Conversely , you would connect the alligator clip to battery positive and probe the ground . The computer safe light will glow red when probing a live circuit and green when probing a ground circuit. It is important to check both circuits since it does no good for a light socket for instance to receive power if the ground side isn't carrying back to the battery negative thereby not completing a circuit. Start at the light socket itself with the switch on and ignition on as well since it's likely the circuit is ignition fed and only live when ignition is on . A word about test lights ; nothing is foolproof so it's best to have a wiring diagram to be certain which wire feeds and which wire grounds . Color codes can be misleading on different make , model & year . I never chance crossing a circuit . It's always best to use the light with the alligator clip to ground since no harm can be caused by grounding a ground circuit . Grounding a live circuit with a computer safe light will just light up the diode on the test light and will be red. Only attach the alligator lead to battery positive to check a ground if your sure the circuit will be a ground. If you do not find power and are not sure which wire or terminal should be power or ground , it's time to check the switch . You'll want to check for power and from what terminal when the switch is on . If none is found , time to check fuses and / or relays marked for the fog lights. Probe both sides of fuse terminals for power and terminal 30 of a relay for power . Terminal 30 feeds terminal 87 which feeds the source I.E. , a fog light. Terminal 87 won't be live until a switch is turned on to power terminal 85 which carries through terminal 86 ( ground or continuous feed to another relay ) . This sounds daunting but keep it simple at first by looking for power continuity ( the ability of volts to flow through a circuit ) to the light socket then at the switch. Look for any fuses and relays marked for fog or auxiliary lights. I am by no means an experienced electrician but the knowledge I've learned may be helpful to you and hopefully to anyone who should experience this or another similar problem . There are regular test lights which aren't computer safe but they can only be used on a circuit that is a known non-computer and low amp circuit. Alternator and starter circuits need high amp test equipment. Hope this helps . Your welcome to post back your findings and post any questions .
