60A fuse popped on a 96 Cherokee

So one day I go over a speed bump and my jeep loses all power. Under the hood I see the 60A fuse is blown. After investigating and fixing possible shorts, fuse still pops upon starting. The motor started but died immediately. I replaced a crank shaft position sensor and cleaned up some contacts and it finally started. It ran fine for about two weeks until yesterday I shut the door and the jeep lost all power. I checked the 60A fuse and once again it's blown. Any suggestions?
 

Hello and welcome to jeeps.com. I haven't seen a diagram of your PDC but I believe this is the fuse that powers your ignition switch . I don't know that you have a problem with the ignition switch itself but what first should be checked is the battery connections. The. One toons at the battery clean and tight , the connections from the PDC to alternator and elsewhere should be checked to start with . You'll find yourself checking all grounds as well. Not only the battery negative to engine block but the PCM and oxygen sensor and continuous grounding for the body grounds too come together either at this ground post or another. Grounds are very important to be clean and tight . All wiring must be inspected for damage to connectors and insulation . You'll want to be sure that the starter connections are clean and tight . Any heavy gauge wiring from the PDC to where it goes should be inspected. In my mind I'm thinking there is either a short or loose connection . The give away is when you posted hitting a bump and slamming the door. If all is well under the hood in terms of CLEAN and TIGHT connections , turn your attention to the ignition switch . Just the fact that slamming the door with the ignition off and causing a no power no start condition lends support to believing that the ignition switch is a possibility and should be considered and inspected. There is no silver bullet , it will take some investigating. I realize your thinking this but asked of this forum where to start . I think that these items I've posted are a good start and am hoping for you that your fix is here somewhere so your trouble is rectified soonest. Hope this helps . At least you've got a good clue , the 60amp fuse. If you can get your hands on a wiring diagram to trace where the fuse feed , that will give more direction than just a guess. You've done some of the work already I've suggested but I don't know exactly what you've done other than "possible shorts" as opposed to what I've suggested. The CPS may have been unnecessary but I realize your desperation. Consider the connections I've posted and move on to the ignition switch next. These problems are process of elimination but a wiring diagram will give more direction. Best of luck and really hope this helps.
 
Thank you for your response. I'll preface by saying I'm by no means a gear head so bear with me. What is a PDC diagram? Battery connections were the first thing I checked while troubleshooting. I made sure they were clean and tight. When I mentioned fixing possible shorts, what I did specifically was trace the red battery cable to what looked like a starter or ignition switch I do not know if those are the same thing, but if I had to guess it would be the starter. There was some exposed wire on what I think is the starter in close proximity to that red battery cable, it looked like a grounding wire to me, I know that most ground wires are green, this one was black with a green stripe, so I re configured the wire so it wasn't close to the battery cable and wrapped it in electrical tape. When I checked it again it was just as I had left it. Upon initial inspection I accidentally touched the exposed wire to the battery cable and the starter fired and sparks flew. So I thought for sure that was the potential problem but upon correcting it it didn't make a bit of difference. Other than that changing the crank shaft position sensor and cleaning up some contacts seemed toget it to run for a week but didn't fix the problem. I'll also add that both times the car lost power it was running. The second time I started it up and shut the door and that's when it died. Upon replacing the fuse it will still start up but it dies immediately after ignition. Different from the first time, the first attempt at the fix we got it to the point where the fuse wouldn't blow but the engine wouldn't catch a spark and ignite. Don't know how we did that, and I don't know how we got it to run without actually fixing the problem. Which means your more than likely right about it being a short or a loose connection. You can probably tell I'm not too car savvy by now but any additional information will help. I appreciate the advice and I will investigate further. If you could point me in the right direction to find a wiring diagram or a general outline or manual of the vehicle online to help me find what I need to find to check what I need to check, that would help out a lot. Thanks again for your time.
 
Your most welcome Patrick. As far as not being automotive inclined , we all had to start somewhere . I'm a diy'er as many of us are . There are many in this forum whom are vastly experienced with jeeps or automotive in general but I try to pull my weight. The question you asked of what is a PDC , that abbreviation is Power Distribution Center. That is the oblong black plastic box under the hood where the fuses and relays reside. I'm sure your already aware of its location and existence since you've found the blown 60amp fuse . Btw , as the owner of your jeep , your already more inclined than your aware . Your making a conscious effort to do what you can . That's a start right there. About obtaining a wiring diagram , try autozone online and establish an account . It's free and they email coupons for discount to boot ! Autozone has wiring diagrams that may be helpful but if the page you need isn't on their site , maybe your dealer's parts counter can furnish one. This spark you mentioned , I'm taking it that you touched the solenoid wire to the battery connection on the starter ? Well , that is what will cause the starter to activate. The battery positive will go from the battery positive to the starter solenoid . There is a smaller gauge wire that comes from the ignition switch under the steering column that goes live when you turn the key to start position. At this point , a wiring diagram may come into play . They are helpful but also confusing if we don't have a legend to what some symbols mean . But just the fact of where the line originates from and goes to is extremely helpful and leads us in the right direction. At least we know where to look to do our visual inspections. Without it , we would find ourselves tracing blindly and removing a lot of wiring harness wrap and other items possibly just to find out we needlessly did so. There are tools like test lights and digital multi meters to help us but we must be cautioned when using them or we can cause damage to,sensitive electronics. Taking a simple voltage reading across the battery posts is harmless but touching a computer circuit with a 12 volt test light is harmful. Before we attempt to check electrical curcuits or use electrical test equipment , we should know some do's & dont's . This is where it's helpful to have a wiring diagram . You cannot know if a wire is routed to the PCM ( power train control module , the jeeps or cars computer) or somewhere else without this diagram. I once found out the hard way. I didn't have my jeeps wiring diagram at THAT time . I just wanted to trace the flow of electricity to confirm if a circuit was complete and found out later the line I probed fed back to the PCM . Not cool . When you ask a 12 volt test light to draw 12 volts from a wire that only flows 5 volts or less , you create an overdraw condition. You also risk burning up something in that circuit. Just want to help you understand how we must be cautious and not cause further damage. Please tread lightly. If you want to poke your head under the dash around where the steering column is with a flashlight just to inspect , feel free . Do be cautious what you touch and please don't use something metallic to probe . Circuits may be live. You may see folks touch screwdrivers to something and make sparks in their testing and repair but let's be careful of that . Ok , inspection is the key here . Hope you can obtain a wiring diagram . You won't need the entire vehicle just engine electrical and what pertains to under the dash may be suffice . Hoping this helps and the problem is found soonest. Your welcome to post back anytime . It's ok to try this yourself but please observe cautions . When handling wiring , think of it as a girls hair . She dosen't like it pulled . We have to be gentle in that way or we cause more problems to our vehicles . Best of luck and post back any questions or findings .
 

I had a look at my factory service manual ( FSM) 1992 . Although a '92 & '96 differ , I thought I would try to find what any 60amp fuse powers. From my PDC , there are three such fuses. One receives from the alternator and two simultaneously power the ignition switch under the dash on the steering column. You did not post you had problems with the charging system so I'm thinking the problems lies with the ignition switch. It stands to reason since you said slamming the door produced a problem which is mysterious in itself to anyone. The circuit from the PDC may be ok if not overheated and wiring insulation isn't charred (hopefully) but the ignition switch may be questionable . A visual inspection of this switch is a good idea . See if any evidence , sight and smell exist. Burned wires will be noticeable , you didn't mention any and hoping that's a good thing. You can CAREFULLY and lightly touch wiring connector plastic plugs to see if any appear loose. Terminal connections should be reasonably tight and plugs fully seated. I'm not certain where to advise you to proceed since wiring branches off . Many circuits obtain their power from a starting point . It is common that a fuse will,power one or several circuits . A 60 amp circuit would be dedicated to a large circuit but a diagram may show smaller circuits that tap power from it as well. The ignition switch pulls heavy amperage but smaller circuits feed their voltage too. If you decide to venture as far as you dare to understand (this is what learning is all about) , have the proper equipment. A computer safe test light is a safe bet . A 12 volt test light is fine IF you know the circuit is NOT a computer circuit. But how do we know without a diagram, right ? This is why I emphasize COMPUTER SAFE. Checking a battery cable with a heavy duty 12 volt test light is ok since it dosen't feed back to the computer but smaller wires in some relay circuits for example may be. Hence the computer safe test light. Basically , a starter circuit or alternator circuit are if heavy amperage and require heavy test lights but usually everything else can be tested with this computer safe test light. This special light uses a diode as its light bulb which only requires a quarter or so of a volt to power its bulb. That won't heavily tax a computer circuit. A 12 volt test light needs something close to 12 volt amperage just to light the bulb. That WILL tax a computer circuit. 12 volt test lights are purpose intended just as computer safe test equipment are. I just wish to advise folks not to make the mistake I once made ( possibly others too) and cost myself a PCM later that year , in the frigid cold. If we are careful, we can achieve results and learn for ourselves . Mechanics and electricians learn much the same way . Hope this may help as well.
 
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