Electrical Gremlins are wearing me out! I'm having a problem with my Econoline pickup. It has a GM tilt column, and SNAP harness. When I turn on the headlights, it blows the headlight fuse in the panel. Thought it was the switch, replaced it with a brand new Borg Warner unit. No change, it still blows the fuse. I completely disconnected the seal beams and removed them. Did a continuity test on the headlight wires, checked OK. Took the wires loose from the dimmer switch in hopes of finding the problem. It still blew the fuse. Then, took the wires loose from the headlight switch one at a time, and it still blew the fuse. (The exception is the blue wire that goes from the headlight fuse on the fuse block to the headlight switch will not blow the fuse if disconnected from the headlight switch, but if that wire is reconnected to the headlight switch - the fuse blows). I also noticed another strange situation. If I ground the fuse block, and put in a new fuse -- and reconnect the battery cable -- it will blow the headlight fuse without turning on the headlight switch. That sounds like a dead short in the fuse panel, but I've checked it and can't see any burn spots or frayed wires. I did try something; took a unused circuit wire from the fuse block, and wired it into the headlight switch, and it blew that fuse too! I replaced the turn signal switch because the brake lights weren't working, and now the brake lights work. (the turn signals were working before the switch was replaced). The ignition switch was old, so I replaced it as well. My question is: with a new headlight switch, is it possible that the headlight switch knob and shaft (which are several years old) could make the fuse blow ? I don't see any burned or cut wires, anywhere. Thanks
Was this something that was working and now isn't, or is this a new install that you can't get to work? And just what are you 'grounding' at the fuse panel?
The headlights were working. The fuse panel has a ground wire. I removed the fuse box from the mount so I could check it for burned wires, etc. Something else, too: my toggle switches for the fuel pump, water pump and radiator fan aren't working either -- and none of the fuses are blown. Really strange. After working on the truck for a couple of days, the only success I've had is getting the brake lights to work -- and that was by replacing the turn signal switch -- which was replaced last month.
Yes - However it is quite unlikely but it can happen. Have you hung the headlight switch loose in air with NO ground wires attached? That will prove/disprove the switch knob/shaft is the culprit. I have troubleshot many a short but never by looking for cut wires or by checking continuity. Those are the opposite techniques for when something DOESN'T get voltage. Sigh ***uming you are still bewildered: Please do not blow any more fuses, that is wasteful and proves nothing. Start by leaving the fuse out of the errant circuit and putting a trouble light in place of the fuse. Turn the headlight switch on and the trouble light should light brightly when the problem exists and dimly once it is fixed. Observing the trouble light is much cheaper than replacing fuses. Next, remove all socketed loads attached to that fuse one at a time starting at the fuse holder until the trouble light goes out. Important that you carefully locate every wire and every place that particular fuse is supplying juice. At this point I would have to await you. I would refer to a diagram but you don't mention the year of your EconPU Hang in there - a new year brings hope for all. Including your headlights
Thanks, Paul -- I'll rig up something to get a light bulb in there, it's a SNAP harness and uses mini blade fuses. The light switch is hung in the air, not installed in the dash.
Grounding problem? Ground wires between engine, frame, and body? Sent from my iPhone using The H.A.M.B. mobile app
Fuses blow for only two reasons; one, it's seeing a dead short to ground, and two, it has too-large of a load connected. In this case, it's probably reason one. And I've never seen a 'ground wire' on a fuse panel; is the wire actually marked 'ground'? You have multiple things wrong, and have replaced multiple items, so the problem isn't likely in the headlight circuit if it's a single issue. To be honest, I'd suspect something at the ignition switch; a mis-connected wire. So a few more questions; from your description, this isn't a stock vehicle with stock wiring, so a factory diagram will be mostly useless. So are you the person who originally wired it? Do you have a diagram that shows what was actually done? You say this is the third turn signal switch in a month, what exactly failed on the old ones? These sorts of issues are extremely difficult to troubleshoot long distance with incomplete information.
Kwik Wire has the manuals online if you don't have a paper copy. http://kwikwire.com/content/Kwik Wire - Instruction Book.pdf I have one in my Ford I did myself with only a minor mis-wire at one of the TL sockets and a bad connection that powers the lighting circuit that jumped off the ignition switch. Look at wire #28 on the instructions, it may help. Mine was loose and I used a big solder sleeve to connect the wires, which did not hold. I took it apart and soldered them.
Yessir. Have fun! (I'd sure like to see a picture of the ground connection on the fuse panel, and also know the logic behind thinking that not having it connected, would cause a fuse to blow)
i'm curious....in the first post it has a Painless style harness , post # 5 has a Kwik Wire panel i have a Kwik Wire in my `30 coupe and no where in the instructions does it have a ground wire going to the panel...except for a wire coming from the horn ****on to ground the horn relay
The only possible reason for a ground wire at a fuse panel would be if the panel contains relays and the ground would be to complete the relay coil circuit...
If you have only one wire (power?) connected to the switch, and it is hanging in the air, it cannot be the switch completing a circuit to anywhere. So if this is the setup, and the fuse blows, the problem can't be at the switch. Sent from my iPad using The H.A.M.B. mobile app
Who's headlight switch connector do you have, did it have wires on it or did you have to make it up? There is a ground wire going to the headlight switch for the courtesy lights, generally the 'White' wire, that would be a good one to check and see if it is going to the right spot.
Going by the KwikWire book, the Blue wire goes to the dimmer. The Red wire is input power. Sent from my iPad using The H.A.M.B. mobile app
One other thought, if this was working before replacing the switches in the column, what happens if you isolate the column by unplugging it? Sent from my iPad using The H.A.M.B. mobile app
The Econoline pickup I have is a tube ch***is -- bed mounted 454/turbo 400. The only thing that's stock on the truck is the body. The wiring harness on the truck is not a Kwik Wire -- that one is on my Falcon -- my bad. It's a "Snap" wiring harness that I installed several years ago and it has worked perfectly until now. I have the book that came with it and installed it correctly with the help of their tech line. They're out of business, so I can't call and ask for help. The headlight switch doesn't have a plug; just individual wires. The fuse panel has two relays, which I had checked and they are working -- that's the reason behind the ground wire to the fuse panel. What I said was when I replace the fuse, and connect the ground wire to the fuse panel, then connect the battery cable, the fuse blows without turning on the headlight switch. The ignition switch plug did have a loose terminal, I took the plug loose and took the loose terminal out and soldered it when I replaced the switch. All the other terminal wires are tight. It worked correctly before, there's only one way the 2 plugs will fit the ignition switch -- I ***ume it's OK -- but I will recheck it. I have a ground wire connected at the headlight switch dome light terminal which is currently unplugged. I replaced the turn signal switch out of frustration, don't know what if anything was wrong with it. I did have to splice the manually operated brake light switch into the white wire of the turn signal switch to make the brake lights work as was done on the old one. Now as to grounds. I have individual ground wires on the tail lights that go to a bolt on the negative battery cable. I have individual grounds on the turn signal housings that go to the body. The motor is grounded to the negative battery cable, so I think the truck is grounded correctly. The turn signal switch wires are all connected at present (except the dome light/ground wire) and it is hanging in the air, not connected to the dash. Thanks to everyone that responded to my plea for help. I read on HAMB that the Snap wiring harnesses aren't the best, but it has worked correctly until now --- and it's what I have --and I need to get it fixed without completely replacing the harness.
I'd first do some triple checking on the headlight switch, to make sure the wires are connected where they are supposed to be connected. Without some pictures from you, it's going to be really hard for us to be much help. A second set of eyes usually is a big help on things like this.
Guessing here, but, it's a gm switch, needing two power supplies, one for the front of the car, one for the rear, often the rear is simply jumped off the power wire feeding the front. You have a definite short, it's not the switch, it's like this, power comes from the fusebox to the switch, the switch directs the power to both the park circuit, and then to the dimmer switch for the headlights. The dimmer switch is merely a splitter, directing power to either low beams or high beams, then power goes to the headlight bulbs, then to ground. That's all there is to a headlight circuit, the turn signals work off the brake switch, power goes to the brake switch from the fusebox, then through the turn switch to the flasher, then to the taillights, then to ground. The rear taillights work off the rear portion of the headlight switch, no connection to the brake light circuit. Check the dimmer switch for corrosion, they're cheap, replace it, it'll be either a gm or ford unit.
I disconnected the wires from the dimmer switch, then disconnected the wires to the dimmer switch from the headlight switch and it still blew the fuse. Going to do some more checking now and see what I can find. Just bought a new knob and shaft for the headlight switch -- long shot and it didn't make any difference. Tried a USA made headlight switch, didn't make any difference either
Well, I found the short. Don't ask me what the wires to the neutral safety switch has to do with the headlights. I installed the shifter after wiring the truck, and the wires were zip tied to the outside of the flexible wire loom. It appears the zip ties chafed them causing a short between the wires. I also should have known that the neutral safety switch was inoperative - allowing the truck to start in gear; I've been starting the truck in neutral. Of course, I just about pulled every wire loose in all the looms before finding the short. The headlight switch no longer blows fuses, and the tail lights are working. I have the headlights completely out and if I have another problem there will replace the wires. BTW, the fuse block no longer blows fuses when grounded, too. This is a lesson to me -- I will never run another wire outside the flexible loom, and will never zip tie exposed wires together. The reason why I didn't put the wires inside the loom was I had rolled electrical tape and completely covered the flexible loom to help it stay water tight. I will only tape the loom up in sections from now on, too. Thanks to everyone that responded and tried to help. Jim
Just a thought, old vehicles didn't usually have a fuse on the headlights, just the tailights. This is a safety issue , you don't want a crummy little fuse blowing out at 11 PM in a thunderstorm at 70 mph on the beltway going round Baltimore. I was checking out the fuses on my Blazer and tha DOES have headlight fuses, but theyre 60 amp. Be very careful how you wire a vehicle or you could be left in the dark. Personally I NEVER put a fuse in my headlight circuit. Sent from my iPad using The H.A.M.B. mobile app
Headlight circuits are generally un-fused and protected by a larger fuse or fusible link closer to the battery and starter wiring. When my HL solder sleeve came loose it was late at night, luckily I still had headlights and brake lights and took a light traffic route home. Just sloppy work on my part when I did the initial wiring.
Older cars (50s though to the 70s for sure, and some into the 40s) had auto-reset circuit breakers for the headlights built-in to the light switch instead of fuses. If you're using a OEM-type headlight switch from that era, you don't need a fuse on the headlights (but still do on the other lights). The downside is these breakers are all about 15 amp rated (12 amp max load), so if you've added lights or are using 'off road' high-wattage lamps, it's pretty easy to exceed the breaker rating. I know from experience that you can't run four 60 watt headlamps (on a four-light car) through the switch and have the high beams stay on long...
Nothing on my truck is original except the body. Most of the aftermarket wiring harnesses I've seen have headlight fuses -- I'm glad mine did or I could have had a fire.
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