Thanks again Charlie! That unit looks exactly like mine.

I've already verified that there are no splices between the battery and the fuse block. I did notice that the main power feed wire was getting extremely hot. This could be an indication of too much current or it could be due to a bad connection. I've seen residential circuit breakers melt due to oxidation on the connection between the wire and the breaker. The hot-to-the-touch wire may or may not be related to the intermittent loss of power to the fuse block... right now I'm operating on the assumption that it is.

I've got some more troubleshooting to do to determine which it is. I'm juggling several projects today, but hope to be able to spend some more time on it.

Thanks again for all your help!

-DV

 

Charlie: I hate to keep imposing on you...you've been so helpful already. Access to my fuse block is not as good as I would like, and my eyesight is not as good as I would like either. Add poor access, poor lighting, and poor eyesight together and you've got a tough problem to solve!

I'd like to pull that main buss bar (see photo) out of the fuse block so I can inspect it and the four connections more closely. Can you tell if there is a little piece of plastic or some other kind of clip that holds that buss bar in the fuseblock?



I did call EZ Wiring by the way. The fellow was not super helpful. He told me the obvious, which was to inspect the connection of the main feed from the battery to the fuse block. I asked about the possibility of getting a diagram of the fuse block itself, and he said that he couldn't get one easily.

I'm trying to be fair here. I'm still not ruling out an installation problem. I certainly don't want EZ Wiring to get a bad rap if it turns out to be something that I did. Normally, I would just live with an intermittent problem like this until it became so bad that I could easily reproduce it (or follow the smoke to the problem). But I'm getting ready to drive this truck 700 miles to Truckstock; I'd like to get it resolved before I leave if I can.

-DV

 

Each female spade connector on that bus has a tab that locks it into the plastic block. To remove that bus you would have to release each of the tabs simultaneously...not a simple/easy task.

To go back to an earlier point regarding the line from the battery to the fuse block...when I said "splice" I am speaking about any connection in the line. I don't think that you have the heavy gauge battery cable running all the way up to your fuse block, somewhere there is a point where the wire from the EZ wiring harness attaches to the "+" voltage supply. Sometimes this is at the starter relay and some times it can be elsewhere depending on how the installer wired it. I agree with your assessment of the current draw due to a possible faulty connection...I guess that what I am trying to say is that I would look outside the fuse block first.

If it were me, I would run another wire directly from the battery to the fuse block and eliminate any/all issuses that may exist within the existing wire run. I would bet that this resolves your problem.

 

Is the wire getting hot in one area or equally over the entire wire? If in one area you likely have a internally broken wire in that area. If the whole wire is getting equally hot, then I'd suspect you are overloading the wire. To fix the former I'd not mess with it, would replace the entire wire. For the latter I'd first run a temporary wire from the battery to the fuse block just to eliminate the possibility of the broken wire then put a VOM on it to see how much current is running thru it with everything on. If the current is high, try pulling one fuse at a time to see what is the high draw device.

Here's a thought, did you ground the cab, the bed, and the engine to the chassis? Is the battery grounded to the cab or to the frame? I like to use the flat lead dipped braided copper ground straps installed with self tapping screws after removing the paint from the metal where they connect. There should be one connecting the cab to the frame and one connecting the bed to the frame, as well as one connecting the engine to the frame ( called bonding). Never depend on the mounting system to provide the ground. I will also ground the fuel tank to the frame if it sits on rubber pads. Finally attach the battery ground cable securely to the frame.
Second thought: is the wire that is getting hot the fuseable link wire? That wire will get warm. A fuseable link wire is nothing more than a slightly undersized wire that is supposed to burn thru like a long fuse if the draw exceeds the max current the fuse block is designed to handle. I understand the function but never understood using a wire for a fuse instead of a heavier wire with a main fuse. I suppose it's to prevent some dumba$$ from replacing the main fuse with a heavier one rather than isolating the heavy draw if it blew regularly, and burning the vehicle down by setting the fuse block on fire. If yours is getting hot rather than warm, I'd be looking for an overdraw device as above.

Wiring connectors are usually not soldered on vehicles, just crimped, even on airliners and military vehicles. Testing has found that solder can/will migrate up the wire making it stiff and concentrating the stress of vibration and temp changes right at the end of the solder. The connectors have (or should have) a strain relief sleeve that crimps over the wire insulation and spreads the vibration and movement point down the wire rather than between the wire and connector without forming a potentially weak unsupported stiff spot. The right type crimpers should be used that crimp both the bare wire and the insulation. If you must use the cheap common staking type crimp plers, then I would recommend using terminals with plastic sleeve and crimping them to the wire insulation. I you feel you must solder then add an inch or so of heat shrink tubing over the soldered connector and wire and shrink it down tight around the wire.

 

Thanks Charlie and AXracer. You are correct, the main feed to the fuse block comes from the starter relay. My ability to track this problem down is greatly impeded by the fact that I can't reproduce it at will. Both times it has done it I've been away from home. I was able to verify with a voltmeter that I had power on one end of that main feed wire (at the starter relay) and that I had no power at the fuse block. I wasn't able to check the connector at the back of the fuse block because the problem went away as soon as I unbolted the fuse block from the firewall.

Yeah, I considered the possibility of a problem with the Ground. The fact that the problem went away (the second time) by simply 'jiggling' the fuse block is what is leading me to suspect a problem at the fuse block. As I said, I can't see inside there real well, but there are signs of high heat in the back side of the fuse block at that main buss bar... that's why I'd like to pull it out of the fuse block for closer inspection. I also noticed that the strain-relief crimp that AXracer mentioned is crimping only the copper wire and not the insulation. I noticed that before but concluded is was probably because that maybe the crimp wouldn't go around the conductor and the insulation because of the size of that wire. That in itself is not a problem but I can see how that could lead to a problem.

It could also be a pinched wire. I've seen that with smaller wires, but this is about a 10 gauge wire... not that easy to pinch in two even if you were trying to. Plus I've done a visual inspection of that wire and don't see any kind of crimp in it. I'm certainly not opposed to running a new wire, but I think that I would probably destroy the evidence of the real problem as soon as I take the original wire loose.

The frustrating part of this whole problem is reproducing it. This would be an easy problem to fix if I could just reproduce it.

If I don't find a conclusive cause of the problem, I think I'm going to just leave the fuse block dangling from the harness underneath the dash. It's ugly as hell, but at least it will allow me to catch it red-handed if it does it again.

In hindsight, I'm kind of wishing that I would have mounted the fuseblock in the engine compartment the way they do in newer cars. At least it would be more accessible.

-DV

 

I'm getting too old to hang upside down under the steering wheel and dash to work on the electrical system. My mini 21 kit came with a fuseblock that had a clip in mounting system, no bolts. I made a plate with a keyhole slot at the bottom and a square hole at the top to accept the mounting pin and locking clip then bolted the plate to the side of the hanging pedal brace under the dash so the fuse block faces the side of the truck. If I need to work on the electrical system I can reach up under the dash, release the locking clip and drop the whole fuse block down and out from under the dash. I also considered mounting it on a hinged plate facing the floor with the hinge attached near the front edge of the dash so the block could be swung down and out from under the dash. Had my power radio antenna not been in the way I might have mounted it in the driver's side kick panel. I also briefly considered mounting it under the pass seat.

 

Doesn't the hot wire from the fuse block to the starter relay get the fusible link spliced in? Could it be that connection or the fusible link?

 

He, he. I hear ya' Chuck! In addition to being too old, I'm too fat and too blind to hang upside down under my dash. I've been thinking about how I could devise some type of quick-release so I can pull the fuse block down to where its more accessible. Sounds like you've got a good solution.

I'm feeling guilty about hijacking "52' fordnut's" thread, but in addition to the feedback on the various harness manufacturers, there's actually some good information in here about location of the fuse block.

Attention all of you future travelers down this road: regardless of whose wiring harness you purchase, mount the fuse block somewhere that is easily accessible because you will need to access it at some point.

-DV

 

I see that in the diagram, but don't see it in the harness. Since you mention it, I'm going to go back and look for it though. The only thing is that if the loose connection were in the fusible link, I'm not sure that the problem would have gone away just by jiggling the fuse block.

Thank's for reminding me about that though; I am going to go back and recheck it.

-DV

 

OK guys, I think I have a plausible explanation for my loss of power to my fuse block, and I wanted to run it by you all to see if it passes the sniff-test.

I completely removed the wire duct from the harness and traced the hot wire from the starter relay to the fuse block. I found no kinks or pinches, nor did I find any fusible link.

I finally stuck a camera up under my dash and got a picture of the back-side of the fuse block:



As you can see from the blue arrow, the main wire coming from the battery (starter relay) is not crimped properly. The crimp should be over the insulation. Even though I was never able to reproduce the intermittent connection at will I believe that this is in fact the problem.

However, I did find a couple of other issues. If you look at the yellow arrow in the photo, there has been some definite overheating on the second hot wire on the main bus. This wire goes to the alternator. I traced this wire completely through to the alternator and again didn't find any kinks, pinches, or shorts, but I did find a jumper wire that went from the alternator to the battery that wasn't supposed to be there.

My theory is that when the intermittent connection on the main power connection from the battery would drop out due to the faulty crimp, all of the current feeding the fuse block would then flow through the 14 gauge wire from the battery to the alternator, and then from the alternator to the fuse block, thus causing the overheating indicated by the yellow arrow. This connection would heat up enough that it too would lose connection, which left me stranded until I restored the faulty connection from the battery by jiggling the fuse block. The problem has probably been going on longer than I realized because it was being masked by that jumper wire from the battery to the alternator.

As far as fixing it, I think that I will solder that main connection. The connection shouldn't get hot enough to melt the solder unless there is a bad connection, and there shouldn't be a bad connection if it's soldered. I also installed a fusible link on the main power wire because well you need that. Instead of removing the jumper from the battery to the alternator, I think I'll remove the jumper from the fuse block to the alternator since that wire is already damaged and not easily fixed.

What do you think?

-DV

 

That wire connection definitely looks to be the source of your problem. From what I can see, that is a workmanship error...the jacket on the wire is clearly not down in the connector as it should be, nor does the jacket look as if it has pulled free. Here are another couple of photos of my fuse block...the first shows the wire as it should be terminated, the second shows how the other two buses are connected to the primary bus where the input wire is attached. You could connect your primary power wire to any of open spots on these buses and be in good shape.
I am a bit disturbed by all the corrosion on your fuse block however, where has that thing been to have been exposed to so much corrosion? I could understand it if it were the OEM panel but to have an aftermarket unit that is in that condition is troubling IMO.

 

The EZ wire kit included a fusible link but you had to splice it in to the power line running from the starter relay to the fuse box. It's a short (4-5 inch) black wire with a large ring terminal.

Is the wire that got hot in the fuse box white? If it is, it's the alternator exciter wire. Are you running a voltage regulator? If you are, the white wire goes to the "I" terminal on the voltage regulator (for a Ford regulator). If you're not running a voltage regulator (ie single wire alternator), the white wire is not used. I have only one wire from the hot on the alternator to the fuse box and it's red.

I don't think the kit includes a wire that runs directly from the alternator to the battery. Was this wire part of the kit? My hot wire from the alternator goes to the fuse box. Since I am running a 100 amp alternator, I had to add the jumper wire from the alternator hot to the battery hot on the starter. This wire was included in the kit but was optional for 80 amp or larger alternators. What size alternator are you using?

I agree that the crimp on the hot wire (red) in the fuse box looks bad. Needs re-crimp or solder.

What color is the jumper from the fuse block to the alternator you plan on removing?

 

I bought my wiring harness from Kwik Wire. http://kwikwire.com/wireharnesses.html It is nice quality & decent price. All the fuse block connections are crimped and soldered. So you don't have to worry about any wires coming loose like some other brands.

My truck is no where near needing the wiring yet so I haven't installed it yet. So my only complaint so far was the shipping price. I bought it a few years ago and they charged me something like $35.00 to ship it from WI to MN!

 

I agree with Charlie, that connector definitely looks like it has a problem or two. They missed when they crimped it, and it looks like the fuse block has gotten wet a lot and the wire and connector is corroded. The corrosion troubles me more than the connection. If the block out where it is exposed to the weather, or do you have a significant leakage problem? First thing that needs to be done is to protect the fuse block from getting wet any more. If it's an issue of water getting someplace it shouldn't be (water should never be getting in under the dash for example) you will need to find the leak and seal it, it's going to cause you a lot of problems down the line. Body leaks can be as difficult to find as electrical problems, water can travel a significant distance from the entry point to where it starts dripping down to a lower point. It also can be driven thru an opening by say the tires, splashing while driving or the wind. A helper with a strong light held out side the truck while you look from the inside with an opaque plastic tarp or HD black trash bags covering the windows might be a good starting point if the water path isn't obvious. If that fails you could place newspaper all over the floor and apply water with a hose or drive it in the rain while watching for the paper to show signs of getting wet. Fresh drips show up very obviously on newspaper. The last method is messy so I'd save it for a last resort. You can go to an art supply store and buy a jar of medium blue powdered tempera paint. dust the entire area with the dry powdered paint. Since tempera is highly water soluble (it's meant to be mixed with water to form the thick water based paint familiar to most grade schoolers) and the blue color darkens considerably when it comes in contact with water, it should show the water path quite easily. To remove the excess paint, blow it out with an air hose and vacuum, avoid trying to wipe it with anything damp. Do a very thorough clean up, even an invisible amount on damp skin is going to turn you or any clothing into a brother of my avatar when you perspire. Fortunately it will wash off with a liberal application of soap in the shower Fabrics can be more problematic especially if they can't be laundered.
AFA where to put the fuseable link, remember it is meant to burn if too much current goes through it. I wouldn't want that to happen under my dash or near any gasoline.

If you can't seal the leak, the next thought would be to put the fuse panel inside a weather tight container. Modern vehicles have a number of them under the hood to protect all the electronics that could be scavenged at the U pull yard or a household container or sporting goods case might be adaptable, check the selection of HD waterproof boxes at an outdoor store or watersports store. holes for the wires to pass thru can be sealed with the never hardening putty like weather seal available in a package of strips at our favorite DIY store or larger RV or auto parts stores.

 

On the question of corrosion: I don't think it's as corroded as it appears in the photo. The fuseblock was installed before we painted the inside of the truck so it got overspray all over it. All that brown that you see on that second wire down is the discoloration of the red wire coming from the alternator caused by the heat.

I'm running a GM style alternator, so the white wire is not used; only the red wire. Come to think of it, that jumper that they call for going from a high output alternator to the starter is essentially the same thing as my jumper from the alternator to the starter relay. If you were to have an interruption of your main power wire, that red alternator wire from the fuseblock would overheat. In addition to adding the fusible link on the main power feed, I'm also going to put a fusible link on the red wire to the alternator just to make sure that doesn't happen again.

To be honest, any wire that connects directly to the battery (or via the starter relay or the starter itself) should have a fusible link just to make sure that you don't burn your truck up.

I'd like to reiterate that if I had it to do all over again I would have placed the fuseblock in a waterproof junction box in the engine compartment. I hate the rat's nest of wires under my dash, and I think that I could have done a better job of tidying the wires up with the fuse block under the hood. Not to mention that it would be more accessible.

Thanks everyone for all the help. Hopefully we've found the culprit and my wife and I are not going to be stranded on the side of the road headed to Truckstock next week.

-DV