Blowing Fuses Constantly

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Andymoor94
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Re: Blowing Fuses Constantly

Postby Andymoor94 » Sat Jun 20, 2020 6:11 pm

jagnut66 wrote:
Sat Jun 20, 2020 2:01 pm
I can imagine that will be something I approach later with a new loom too
Go for it, it's not as frightening as you may at first think! :P
Best wishes,
Mike.
Thanks for the words of encouragement. This wasn't really as scary as I thought it was. The electrics aren't all that difficult, now I've seen the diagram :D
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Re: Blowing Fuses Constantly

Postby Andymoor94 » Sat Aug 01, 2020 7:21 pm

Bringing up an old thread.
Seems something else is now causing the fuse to blow. Removing the trafficators wire seemed to stop the issue, but then I put them back in and... All fine? Really? Then it blew again today.

I am about to lose my frigging mind!!
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Re: Blowing Fuses Constantly

Postby myoldjalopy » Sun Aug 02, 2020 11:08 am

But I thought you said you had tracked down the problem to the heater, not the trafficator?

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Re: Blowing Fuses Constantly

Postby Andymoor94 » Sun Aug 02, 2020 11:13 am

myoldjalopy wrote:
Sun Aug 02, 2020 11:08 am
But I thought you said you had tracked down the problem to the heater, not the trafficator?
I did, just by chance these are playing up now
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jagnut66
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Re: Blowing Fuses Constantly

Postby jagnut66 » Sun Aug 02, 2020 6:18 pm

Trafficator wiring is really simple, a single live wire to each trafficator, which then earths through the body of the trafficator when operated.
The hard part might be pulling through a replacement live (not supplied in with replacement looms :roll: ).
Mine were still working, so I have left the original feed wires in place but if they start playing up (or blowing the fuse) the first thing I try will be replacing them both, which is what you may have to do, as if its blowing the fuse when operated this is the simplest and cheapest thing to replace / eliminate.
Hopefully this will fix them but someone will be along to explain your options / what can go wrong with the trafficators themselves if replacing the live feeds doesn't fix it.
Replacement trafficators (that work) can vary in price, so look around before you purchase, if you need to replace them, that is.

Oh, and loosing your mind is par for the course with classic car ownership :wink: ...............
Best wishes,
Mike.
1954 Series 2 on axle stands needing more welding......

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Re: Blowing Fuses Constantly

Postby myoldjalopy » Sun Aug 02, 2020 6:48 pm

Unfortunately, we don't know for sure if it is anything to do with the trafficators - first the OP thought it was, then it was thought to be the heater, and now back to trafficators again. It would be helpful to have a bit more detail on exactly how the trafficators are 'playing up'.......is trafficator operation what causes the fuse to blow? Or does the fuse still blow when just ignition on, as reported near the beginning of this post?

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Re: Blowing Fuses Constantly

Postby Andymoor94 » Sun Aug 02, 2020 6:56 pm

myoldjalopy wrote:
Sun Aug 02, 2020 6:48 pm
Unfortunately, we don't know for sure if it is anything to do with the trafficators - first the OP thought it was, then it was thought to be the heater, and now back to trafficators again. It would be helpful to have a bit more detail on exactly how the trafficators are 'playing up'.......is trafficator operation what causes the fuse to blow? Or does the fuse still blow when just ignition on, as reported near the beginning of this post?
Basically, blows when I turn the ignition and removing the trafficators wire from the fuse stopped it from blowing, but the crap part is that's actually the exact same thing that made me believe the heater was causing it. It all stopped when I disconnected it :(
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simmitc
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Re: Blowing Fuses Constantly

Postby simmitc » Mon Aug 03, 2020 9:07 am

This is a long thread with lots of quotes in it, so it's probably worth just recapping to make sure that we know the current position. Am I correct in understanding that
a) With nothing switched on, the fuse is OK.
b) When you switch on the ignition, the fuse blows before you operate any other switches.
c) You previously believed that the fault was with the heater as when you disconnected it, the fuse did not blow.
d) The heater is now reconnected and working correctly.
e) You know believe that the fault lies with the trafficators as you have disconnected them and the fuse now does not blow.

Can you please confirm or correct the above.

Are the trafficators now connected and working, or still disconnected? If they are causing the fuse to blow before being operated, then the fault will be the wire to the switch or the switch itself as the wires to the trafficators will not have any power until the switch is operated.

What amperage fuse are you fitting?

Can you post of photo of your fuse box please.

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Re: Blowing Fuses Constantly

Postby Andymoor94 » Mon Aug 03, 2020 9:37 am

simmitc wrote:
Mon Aug 03, 2020 9:07 am
This is a long thread with lots of quotes in it, so it's probably worth just recapping to make sure that we know the current position. Am I correct in understanding that
a) With nothing switched on, the fuse is OK.
b) When you switch on the ignition, the fuse blows before you operate any other switches.
c) You previously believed that the fault was with the heater as when you disconnected it, the fuse did not blow.
d) The heater is now reconnected and working correctly.
e) You know believe that the fault lies with the trafficators as you have disconnected them and the fuse now does not blow.

Can you please confirm or correct the above.

Are the trafficators now connected and working, or still disconnected? If they are causing the fuse to blow before being operated, then the fault will be the wire to the switch or the switch itself as the wires to the trafficators will not have any power until the switch is operated.

What amperage fuse are you fitting?

Can you post of photo of your fuse box please.
All correct apart from D. Heater still disconnected.
Trafficators are still disconnected whilst I rebuild the switch (Separate issue I had with trafficators not staying up).

But yes, the 35A fuse was blowing upon turning the ignition (But I didn't start the car, just turned the key). Seemingly nothing active/turned on (i.e. wiper switch down, lights of, brake pedal not pushed, trafficators not activated however it's worth knowing I have a very sensitive switch that activates the left side trafficator very easily, sometimes over bumps).

Fuse picture attached. Preemptive note, the short green wire is replacing a severed brass line that originally connected those two terminals.
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Re: Blowing Fuses Constantly

Postby simmitc » Mon Aug 03, 2020 10:11 am

That's a beautifully clear picture, thank you. Also a lovely looking totally original fuse box and wiring loom :D However, I'm not sure that original in this case is necessarily good. I think it fair to say that the newness has worn off :-?

"wiper switch down" confuses me. I'm used to the earlier round pull-on-push-off switches and the later "toggle" switches which would usually be up for off and down for on.

In the short term, you could remove all the wires from the fused side of the box and then replace them one by one until you identify which one causes the fuse to blow, and then trace that to see where the problem lies.

Longer term, insulation on a loom of that age could be cracking anywhere and causing problems, and I do think that a new loom and fusebox would be a good investment.

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Re: Blowing Fuses Constantly

Postby Andymoor94 » Mon Aug 03, 2020 10:22 am

simmitc wrote:
Mon Aug 03, 2020 10:11 am
That's a beautifully clear picture, thank you. Also a lovely looking totally original fuse box and wiring loom :D However, I'm not sure that original in this case is necessarily good. I think it fair to say that the newness has worn off :-?

"wiper switch down" confuses me. I'm used to the earlier round pull-on-push-off switches and the later "toggle" switches which would usually be up for off and down for on.

In the short term, you could remove all the wires from the fused side of the box and then replace them one by one until you identify which one causes the fuse to blow, and then trace that to see where the problem lies.

Longer term, insulation on a loom of that age could be cracking anywhere and causing problems, and I do think that a new loom and fusebox would be a good investment.
Wiper switch down is because the switch is on top of the dashboard, vertical. It's a push and pull like the rest, just pointing up :D

Wiring loom and fuse box already in my ESM basket, just waiting for a sufficient amount of time to get it done in a day or two. I can only find a wiring diagram for a 1000 though, do you know where I could find a S2 4 door?

What do you mean by "fused" side? Still very new to this. I presume you're referring to everything on the bottom right?
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Re: Blowing Fuses Constantly

Postby simmitc » Mon Aug 03, 2020 10:58 am

When the fuse is removed (or blown) and the ignition on, then one side will have 12 volts present, unfused. The other side, protected by the fuse, will have zero volts. This is the fused side. Wiring diagrams are available, hopefully someone will be able to direct you shortly.

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Re: Blowing Fuses Constantly

Postby myoldjalopy » Mon Aug 03, 2020 11:20 am

Before going to the trouble of fitting a new loom, it would be good to try and identify the short - might be a quick, easy fix.
The heater and the trafficators may have been red herrings, hard to say.
If the fuse blows with only ignition 'on' and all switches off, one thing you could do is connect a 12v test lamp across the clips of the fuse which blows. With all other switches 'off', turn the ignition on and if the lamp lights there is a short which is causing current to flow in one of the circuits protected by the fuse. Turn off the ignition and remove one of the wires from the fused side and tighten up the others again in the fuse box. Turn ignition on again. If you have removed the shorted wire the lamp will not light. Keep doing this until you have found the shorted wire. It will help to have an assistant to turn the ignition on and off as required as you don't want the ignition left on while you are connecting and disconnecting wires. In fact, the ignition should not be on for any length of time without the engine running or the coil can get damaged

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Re: Blowing Fuses Constantly

Postby oliver90owner » Mon Aug 03, 2020 11:35 am

It might take 5 seconds to remove the feed wire from the coil? Simple solutions to simple problems.🙂

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Re: Blowing Fuses Constantly

Postby myoldjalopy » Mon Aug 03, 2020 11:48 am

oliver90owner wrote:
Mon Aug 03, 2020 11:35 am
It might take 5 seconds to remove the feed wire from the coil? Simple solutions to simple problems.🙂
True - but its still not good practice to be disconnecting and connecting various wires on a live circuit.

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Re: Blowing Fuses Constantly

Postby Andymoor94 » Mon Aug 03, 2020 1:29 pm

myoldjalopy wrote:
Mon Aug 03, 2020 11:48 am
oliver90owner wrote:
Mon Aug 03, 2020 11:35 am
It might take 5 seconds to remove the feed wire from the coil? Simple solutions to simple problems.🙂
True - but its still not good practice to be disconnecting and connecting various wires on a live circuit.
That's not a concern, I make sure everything is off when changing wiring anyway, so thanks for the useful reiteration. Worst thing I ever did a few years ago was reconnect a battery cable that came loose from a running Audi A4. Buggered the alternator in doing so :o
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Re: Blowing Fuses Constantly

Postby myoldjalopy » Mon Aug 03, 2020 2:27 pm

Oh dear, yes. I'll never forget the alternator fitting advice given to me many years ago by an old-time Cornish mechanic:
"Don't furget to disconnect th' baattery 'fore you fit th'alternator or you'll f***k 'n up! Knaw what I mean do 'ee?"
Words to live by 8)

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Re: Blowing Fuses Constantly

Postby Andymoor94 » Mon Aug 03, 2020 2:43 pm

myoldjalopy wrote:
Mon Aug 03, 2020 2:27 pm
Oh dear, yes. I'll never forget the alternator fitting advice given to me many years ago by an old-time Cornish mechanic:
"Don't furget to disconnect th' baattery 'fore you fit th'alternator or you'll f***k 'n up! Knaw what I mean do 'ee?"
Words to live by 8)
Ah yes, the old ancient proverb
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oliver90owner
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Re: Blowing Fuses Constantly

Postby oliver90owner » Mon Aug 03, 2020 2:47 pm

myoldjalopy wrote:
Mon Aug 03, 2020 11:48 am
oliver90owner wrote:
Mon Aug 03, 2020 11:35 am
It might take 5 seconds to remove the feed wire from the coil? Simple solutions to simple problems.🙂
True - but its still not good practice to be disconnecting and connecting various wires on a live circuit.
My, oh my, disconnect while the ignition switch is off if you are that worried!

Never removed a battery lead either? Is that not always live, until disconnected (unless the battery is totally discharged)?

The contact points sever the circuit many times a second, producing multiple sparks at the plugs, when the engine is running but nothing at all happens if one opens the contact points (or removes the feed from the coil terminal while the ignition is off.

How else is the coil tested, might I ask, too.

We have had more than enough on the forum complaining of no spark, only to find the supply lead has failed, fallen off or the coil or the pig-tail lead is open circuit.

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Re: Blowing Fuses Constantly

Postby myoldjalopy » Mon Aug 03, 2020 4:17 pm

"My, oh my, disconnect while the ignition switch is off if you are that worried!"
Sarcastic, sneering comments are not welcome on this forum. Most people on here are trying to help others - not prove how 'superior' they are.


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