Can you use normal solder in car wiring?

[d215yq]

Hi all,

I noticed the car getting to 100+ degrees in traffic so checked and saw that the fan wire had melted its own insulation and the top half of the plastic 20A fuse where the aux fan wire piggy backs off a 20A fuse.

Bit of history - way before my ownership the original circuit for the aux fan melted completely distorting that part of the fusebox - so that feed cannot be used. As such the Previous Owner just found the wire to the aux fan circuit and put it between another 20A fuse and it's holder pin and thus piggy backed off another circuit. This set up has worked over 6 years until now and it seems the cause of the melted fuse is not over current/piggy backing (metal bit of fuse still intact) but the poor connection from the stranded wire being held in by friction (probably only one strand taking all the current and thus getting hot - as the plastic fuse and wire casing both show signs of melting/burning.

Is there any reason i can't just solder the wire to the fuse pin to avoid having to jam the wire between the fuse and pin and therefore getting a bad connection and the same happenign again? I only ask as I see every connection on the car is screw or clip and there's no solder anywhere so not sure if the heat of the engine bay means you cannot solder thigns together?

 

[AnthonyUK]

Regular solder melts at 180-190'c so it should be OK.
Solder is not generally used only because it would take longer during manufacture I presume.
My background is in Avionics where historically nearly all connections are either crimped or soldered and the operating areas are significantly more hostile to electronics than a car.

 

[Blobcat]

Can't see why not, although I tend to crimp most wiring I do in cars

 

[LostKiwi]

I've used solder for wiring repairs for years and years. On some of the Motorsport cars we built from scratch connectors were crimped and soldered. Never had a problem.

 

[onefortheroad]

Yes . But not in srs systems.

 

[V6Matty]

You could get a fuse tap and then just crimp a new connection to the extended wire, might be safer long term than trying to solder into the existing

 

[d215yq]

Thanks guys, pretty clear answer, will solder it all in properly, although the original was 20A I also might piggy back off a smaller 16A fuse as the wire is very thin and can't think a electric cooling fan will take 20A of power, and that will add better safety too.

 

[DREAMER NO2]

Might be a problem in the fan motors to get the wire to them so hot .

 

[AnthonyUK]

Might be a problem in the fan motors to get the wire to them so hot .

They should only get hot if the cable is not capable of safely handling the current.

 

[d215yq]

Might be a problem in the fan motors to get the wire to them so hot .

The wire hasn't got hot itself, it's where it was badly jammed between fuse and holder - as it's stranded wire probably one or two strands of 15 taking all the current. I've no idea what caused the whole thing to melt in the first place but one issue in over 6 years doesn't suggest it's recurring - and the motor will sometimes be going constantly while driving up hills in 35 degrees heat etc and not had a problem.

 

[jacketee]

Solder can become brittle with vibration that's why they crimp car wiring.