Turn signal circuit fuse is "hot-to-touch" - excessively warm

[emoze]

Turn signal circuit fuse is "hot-to-touch" - excessively warm to touch when Ign ON: just noticed while replacing radio fuse yesterday - back story: maybe 15 yrs ago that TS fuse overheated and smoked-melted the socket in bulkhead fuse block - (replacing the fuse block is/was not a task i wanted, or had time to do)

i just figured out a bypass and wired in a separate circuit with separate fuse & it has worked ever since -

BUT finding the fuse to be hot with ign in acc mode yesterday is alarming cuz that means current is going to ground thru something (none of the lights are illuminated)

any of you have had experience like this ??

fwiw: this is an '84 truck - 454-auto, camper special I have owned since 1985 - probly had 100K miles on it when the TS circuit short originally happened (in a middle of night long-drive-home of course)

'yep - i'll start doing some wire-by-wire troubleshooting, (which ain't too easy under the dash for an oldster like me)

TIA

 

[fast 99]

Visual inspection and start disconnecting circuits to find the offending area. Then proceed from there. Install a circuit breaker or limiter of some kind. Do not install a higher amp fuse such as a 30, unless you like replacing harnesses.

 

[Edelbrock]

Ya if you have fuses overheating, I would immediate suspect that the incorrect fuse has been installed or the connections on either end of the fuse have a bad connection. The whole purpose of the fuse is the prevent overheating of the wiring, melting of plastic, etc. So if the fuse is not preventing this, then why? If there is a short then the fuse should pop right away, unless you have the wrong fuse or bad fuse connections.

Try installing a low rated fuse in there when the system is powered up but not in use. For example:

Lets say say the radio is a 20 AMP fuse.
Take that fuse out, and replace it with a 2 AMP.
Then start the car (with the radio turned off).

The radio should be energized, but not actually drawing any power. If the 2 AMP pops, you know you have a short on that circuit.

If you see a fuse in there that is a 20 or 15 or 30 or whatever, that doesn't necessarily mean that the correct fuse is there. The previous owner might have put the wrong one there. So I would check the owners manual or fuse box cover for the proper rating. Then I would use something to clean the fuse connections. The fuse itself and the socket that it goes into.

 

[emoze]

Ya if you have fuses overheating, I would immediate suspect that the incorrect fuse has been installed or the connections on either end of the fuse have a bad connection.

it's not about the radio fuse (which is 15A by the book fwiw)

good idea to try a low-amp fuse as a general test procedure,

- the correct AMP TS fuse is installed in the isolated circuit

cannot install a test fuse into the burned melted TS fuse socket for obvious reasons

- yes, i have checked the manual ( more times than you can count !) - all fuses are correct & always have been

Try installing a low rated fuse in there when the system is powered up but not in use. For example:

Lets say say the radio is a 20 AMP fuse.
Take that fuse out, and replace it with a 2 AMP.
Then start the car (with the radio turned off).

The radio should be energized, but not actually drawing any power. If the 2 AMP pops, you know you have a short on that circuit.

check the owners manual or fuse box cover for the proper rating.

 

[Ricko1966]

I'd temporarily remove the existing offending fuse put a DMM on the leads see how much voltage you are drawing. Now remove fuses one at a time,watching for the meter to drop. When it drops you've found the offending circuit,you can concentrate on that circuit to find the offending branch. Meter doesn't drop,disconnect the alternator see if it drops. The wiper motor,blower motor,etc. until the meter drops. If you are lucky it will actually draw enough to light a small bulb that way you can use a bulb instead of a meter and it will be obvious when you disconnect the offending circuit. Be sure to wiggle vigorously all the harnesses a short in the harness will show its self as a blinking light

 

[emoze]

as usual i asked the wrong question:

just want to know if any of you have had TS circuit experience like this ??

 

[Ricko1966]

as usual i asked the wrong question:

just want to know if any of you have had TS circuit experience like this ??

I've had to trouble shoot,many electrical draws and shorts with the procedure I listed. Fuse amperage is not a cause of your issue a draw is the cause. It getting hot is a symptom if there were no draw or short you could put a million amp fuse in there with no issue,fuse is only in play in a short or overload condition. Go change the fuse in a circuit that has no issues,put the biggest fuse you can find in there it will not get hot.

 

[emoze]

I've had to trouble shoot,many electrical draws and shorts with the procedure I listed. Fuse amperage is not a cause of your issue a draw is the cause. It getting hot is a symptom if there were no draw or short you could out a million amp fuse in there with no issue,fuses is only play in a short or overload condition.

i tho't i made it clear enuf that i believe there is a unusual current draw on a circuit that has no known activated devices

- just wanted to see if any of y'all had a specific current draw experience in the TS fused circuit & had found a solution

if so, it would save me hours of troubleshooting

- crowdsourcing is what i think these forums are good for

i suppose if we speculate enuf - we might suspect a "leakage" in the TS switch assembly inside the column -

i don't want to go thru all that column & wire by wire disassembly if somebody else already solved it

(example: i also have a '93 Ford e350 which has known issues inside the column assy & have BTDT ) (it's a PITA )

 

[Ricko1966]

i tho't i made it clear enuf that i believe there is a unusual current draw on a circuit that has no known activated devices

- just wanted to see if any of y'all had a specific current draw experience in the TS fused circuit & had found a solution

if so, it would save me hours of troubleshooting

- crowdsourcing is what i think these forums are good for

i suppose if we speculate enuf - we might suspect a "leakage" in the TS switch assembly inside the column -

i don't want to go thru all that column & wire by wire disassembly if somebody else already solved it

(example: i also have a '93 Ford e350 which has known issues inside the column assy & have BTDT ) (it's a PITA )

Yes it is feeding current somewhere it shouldn't that is why I said pull fuses 1 and components one at a time so we can determine if it is trying to backfeed another circuit or component.it is not a dead short or it would pop the fuse or burn the wire. See if the meter drops when you unplug the turnsignal switch at the base of the column. If so post back I can tell you where to go next. Right where you said it, no known activated devices.Im looking for unknown activated devices.

 

[Edelbrock]

The only other suggestion that I can come up with is this:

- crowdsourcing is what i think these forums are good for

Agreed.

As far as the issue, the only other thing I can contribute would be:

(Like the stereo fuse thing, this is just a general idea - not specific to your exact circuit).

Lets say you have an electrical draw on a fuse that controls:

Sun roof
Power mirrors
Rear defroster
power seats.

Chances are, the problem is in the device rather than the wires going to it. So you would check for draw, and then start unplugging each thing until the draw disappears (as I'm typing this, I see another comment appear on the page that hits on this). Does unplugging the sun roof stop the draw? Power seats? Rear defroster and so on. If you unplug EVERYTHING and there is still a draw, then it is in fact the wiring. So at that point, you pull the fuse, and then check for continuity between the power plug at each item such as the plug that goes to the sunroof. If you are lucky, the volt meter will tell you which set of wires have the draw, because that wire would have the lowest continuity (sorter distance to ground than the other wires). You would need a good volt meter, on the right setting - but you MIGHT be able to isolate which wire has the draw this way - but I wouldn't count on it.

 

[Snoots]

as usual i asked the wrong question:

just want to know if any of you have had TS circuit experience like this ??

No

 

[Sad Sack]

Hope I don't.

 

[YakkoWarner]

Never seen that sort of problem - but if the fuse cannot be removed due to melting itself to the plastic of the holder, I would be inclined to cut it in half with a dremel tool or something to ensure that no current was going through it. If it still feels hot, then there is a short elsewhere in the fuse panel near it.

 

[emoze]

Never seen that sort of problem - but if the fuse cannot be removed due to melting itself to the plastic of the holder, I would be inclined to cut it in half with a dremel tool or something to ensure that no current was going through it. If it still feels hot, then there is a short elsewhere in the fuse panel near it.

per o.p. the bad fuse was removed from melted socket & bypassed about 15/ yrs ago

 

[YakkoWarner]

My bad - I misread it and thought that he couldn't get the fuse out because it was melted in. That what I get for reading stuff half-asleep.