Hoping for some help, went over the Tobin Bridge in Boston tonight (As an aside, maybe the worst paved road in America. The pot holes are something to be seen) I could not avoid them all and after hitting several, all of my lights went dark. Headlights, Fogs and tail lights. Something must have come loose. Made it back to Marblehead and put the car away after an unnerving ride home in the dark. Any clues or places to start? Thanks
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Start with the fuse block under the dash on the left side. Since it is fog and tail lights they are probably on their own fuse apart from the headlights.
Yeah,
Either a fuse popped loose or the main feed wire for the headlight switch has come loose. You'll have to lie down on the driver's side floor and look up at the headlight switch to see if there is a wire loose and hanging around near the switch. The fuse panel is up in there on the side, too.
Yeah, most probably the main feed wire came off the switch. It is also possible the fuse popped if the hot wire came off and touched metal.
If you find the loose wire, squeeze the curved tangs inside to a more closed position to make it a permanent fix. This connector should have a plastic cover on it. If it doesn't I'd replace it with one that does.
Fog lights and headlights are two different circuits. Fog light usually fused in line while the headlight switch has a dedicated fuse in the fuse bank.
Ok, I’m going now to check it out. Thanks and I’ll keep you all updated.
So this seemed to be hanging with nothing attached. Where does it connect to?
@DannyP posted:Yeah, most probably the main feed wire came off the switch. It is also possible the fuse popped if the hot wire came off and touched metal.
If you find the loose wire, squeeze the curved tangs inside to a more closed position to make it a permanent fix. This connector should have a plastic cover on it. If it doesn't I'd replace it with one that does.
thats the exact fitting that vibrated loose on the coil stranding me in BFE for awhile till i figured it out
@Marc Orloff posted:So this seemed to be hanging with nothing attached. Where does it connect to?
I'd look on the floor for a small nut. I'd guess it was possibly on the ignition switch. You're going to have to get under there. Like on your back under the dash. Yeah, it sucks.
So we think the yellow switch connected to the ignition switch. Would that cause the lights to go out. Im not sure where its connected and how it relates to the lights though
Assume that paint on the yellow bit and not electrical burn marks. Assume it is a fuse holder? Not many switches with screw on connectors - most are the spade connectors. Fortunately wire is not too long so should be close by.
That yellow cylinder is a fuse holder "external" to the fuse panel but the fuse is supposed to blow and open the circuit - Yours looks like the fuse somehow stayed connected and charred the fuse holder. Either way, not good.
My guess is that it might be for your fog lights but it's tough to say without being there. If the fog lights were added after the car was built and with a separate foglight switch, then the most common way to fuse them is with one of those in-line fuses (yellow cylinder) so find the switch and see if it is missing a wire (exposed tab with nothing attached). Whatever it attaches to should be within reach of the ring end of the wire. The cylinder should pop apart lengthwise (use your thumbnail) to expose the replaceable fuse, probably a 10 - 15 amp. I'm curious as to what you see inside of it - please let me know, because it's not supposed to char like that.
Where the ring tab on the end of the hanging wire goes is your next discovery. If you don't have a separate foglight switch then maybe everything is running off of the headlight switch which, again, might have a tab expecting to hold the wire that's dangling. There are a lot of different ways these cars have been wired, so we'll take it one step at a time - Open the fuse holder and see what the damage is, find a light switch missing one wire and then we'll see about getting you lit up again.
A mechanic buddy who has helped me with small issues with this said the yellow has no function. So do we think it’s on the main headlight switch? Does the fog jump to the main? Trying to figure why nothing goes on and how to pinpoint my search.
I also just thought that, IF the other end of that fuse holder (the opposite end from the ring terminal) is connected to the headlight switch AND that ring end fell off of the foglight switch or some other place and then shorted to ground, even momentarily, then it would take out the headlight switch fuse and all of your lights would instantly go out. Sound familiar?
Or......... It could have been the "Mystic River Witch" messing wit'cha!
For those of you unfamiliar with Bahsten, the "Mystic-Tobin Bridge" is roughly the same as the Brooklynn Bridge in NYC but with 3X more traffic. Losing your lights in the dark on there and then driving north for a while on RT 1 (east coast) in traffic must have been pretty harrowing...
very scary drive. Plus top up as it was raining. It isn’t connected to the headlight switch , it seems to weave its way into a bunch of other wires, but not the switch.
OK, more to the point, the headlight switch has one 12 Volt wire going in, and in turn controls the headlights, the parking lights, the dash lights and the tail lights. If the fog lights are also connected via the headlight switch, then if you somehow lose or blow the headlight fuse everything goes out - poof. If that feed wire were to become disconnected, the same thing would happen.
How, exactly, do you turn the fog lights on, and do they go out when the headlight switch is off?
Of course, the first step is to check for a blown or missing fuse in the fuse panel located in the kick panel. If your car is a Vintage, then others on here may help with which fuse to look for and where on the panel.
Gordon, Mark will have to verify, but is that fuse holder charred, or is it just black paint overspray?
Any thoughts as to the size of the fuse for headlights? 5?
It's sounding more and more to me like you lost the headlight switch or headlight relay (or the 12v feed to either). The mysterious yellow/black fuse holder may offer a clue to the feed question.
Since our cars are hand crafted, someone will probably need to get upside down in the floorboard with a volt ohm meter to trace it out.
@Marc Orloff posted:Any thoughts as to the size of the fuse for headlights? 5?
More astute members will correct me if I’m wrong but 5A would work if you have headlight relays. If not your headlight would be at least a 15A if not a 25 or 30. UN relayed headlights an fans and/or AC are the two biggest draws in an auto electric system.
Which goes back to the question: is that fuse holder burnt or simply discolored? I’m guessing (hoping) it’s overspray.
@barncobob posted:thats the exact fitting that vibrated loose on the coil stranding me in BFE for awhile till i figured it out
That’s why I like to say “All progress isn’t forward.” Stacons are a relatively new development. BITD, all those connection were either ring terminals or the kind where you push a wire end in a hole and a screw tightens a tab onto it
All the original Bosch black coils have the Stacon tabs attached with a nut and washer. I take them off and attach the wires with a ring terminal and the nut and washer.
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Some thoughts from a distant observer with no real facts in hand.
- The wire on that inline fuse holder looks very thin, and not made to carry the current for headlights, let alone headlights AND running lights and other stuff.
- There aren't many lighting-related things it might have connected to with a ring connector.
- Those fuse holders usually contain low-current fuses, not 20- or 30-amp fuses.
- One of the few under-dash electrical devices with screw connectors is (as Danny said) the ignition switch.
- I'm guessing this was connected to the ignition switch (maybe the accessory post) and goes to a relay that, in turn, brings power from the fuse block to the headlight switch. This is a not uncommon way of making sure no lights will work with the ignition off.
That nut could have come loose months ago (and buried itself in the carpet or coco mat), with the jolt from the bridge finally knocking the wire off the terminal.
Again, these are guesses. It's important to know what that fuse holder connects to and if it's burned or not.
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I am more certain than not that that fuse holder is charred. It looks to have bubbled slightly near the top.
Replaced the 20 amp fuse and everything works again. Thanks for all the help- I’m feeling very accomplished for a Sunday!
@Marc Orloff posted:I see no wires loose but there is a blown 20 amp fuse. The question is why did it pop
Just a guess: that yellow wire is (was) powering some add-on accessory (fog lights?) and it grounded out in the process of coming disconnected.
@Marc Orloff posted:I see no wires loose but there is a blown 20 amp fuse. The question is why did it pop
Somewhere in the mix is a loose wire or a loose connection. Fuses don't generally blow unless they get unintentionally grounded somewhere.
@Marc Orloff posted:Replaced the 20 amp fuse and everything works again. Thanks for all the help- I’m feeling very accomplished for a Sunday!
I’d still get under your dash and look for a stud that’s missing a nut and washer (and the connection to that yellow wire)
I think you are right. No loose wires to the switches, I will check for an empty one. At least fir this moment, not driving in the dark
If everything came back on when the bad 20a fuse was replaced, it means that all your lighting current is wired through that fuse. It may be that 20 amps is just barely enough to carry the load and the fuse just gave up.
Fuses are used to prevent wires from melting down and relays are used to increase the lifetime of switches.
You could just keep an extra 20a fuse in the car or do some rewiring to spread the load across more than one fuse. I'd personally add a headlight relay to protect the switches, but there are a lot of cars running around without them.
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Scratching head here.
So you didn't connect the dangling yellow wire to anything, but everything works again after replacing a fuse?
So, the fuse you replaced was in the fuse panel and not in the yellow fuse holder, right?
Then Robert and Dave are right. You probably haven't solved the problem yet, just delayed the next occurrence. Fuses don't 'just blow'.
At the very least, I'd tape up the connector at the end of the yellow wire and secure it (maybe with zip ties) so it can't flop around and contact anything. Better yet, open the fuse holder and remove the fuse. (I'm guessing that fuse is now blown, too.)
If the stray yellow wire wasn't the culprit, it's pretty likely there is some other loose wire that caused all the dark.
Speedster fun dies in darkness.
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find ur answer at Lucas British Electrics"he's the prince of darkness"
Glad you were a successful Electrical Tech, @Marc Orloff!
Along with Mitch's suggestion of taping up that yellow wire hanging around so it doesn't possibly short to something (besides having the good looks of Brad Pitt, Mitch is also wickit smaht) I would also put an extra one or two 20 amp fuses somewhere in the car, just in case. You know it blew once and you now know where to replace it - Practice that in the dark a few times, just in case!
Isn't being "In the Madness" wonderful? 
I also investigated the yellow wire. It would definitely take a tube fuse, which there was not one even in there. Not sure what it was or why it was there. Maybe Alan could opine on it as he finished up the car. I am also going to look again tomorrow and see if any wires from any of the four corners of lights maybe loosened and grounded out creating the fuse issue. I’ve never had an issue running the lights so guessing something is loose and caused a short with the pot holes. Where is our tax money going anyway???
Could it go to a cigarette lighter/12v phone charger?
20A fuse fix , OK wiggle some wires and try to get it to pop a fuse again, that's the only you'll find an issue if there is one. The speedster was previously wired before it arrived here from Florida, I do recall that I only fixed two gauge connection issues. Lighting circuits are simple: 12v fused power source gets connected to a input on a switch , from the output side of the switch power continues to the + on the light which has a ground to complete the circuit. Keeping the driving light and headlight circuit separate is necessary to avoid total lights out. ........All part of the Madness :~)
Not on this car, no addl wiring. Thanks Alan!
