Turn Signal Switch Nightmare

[smonroeaz]

I have had my 70 Bronco for 24 years, and all of the sudden, in the last 6 months have had to replace the turn signal switch 4 times as it keeps melting. Any suggestions??%)

 

[rydog1130]

check your fuse box? what size fuse is in there? follow all your wires make sure nothing is rubbed through

 

[Broncobowsher]

You have a short or overload somewhere. Maybe not enough to blow the fuse.

 

[September 1972]

Exactly, the short is below the heat required to blow the fuse link but can start a fire. An amp gauge in series between the fuse link and the starter relay post would be the starting point. The horn and brake lights is always hot and a soft short in a turn signal or the horn, likely the horn would overheat the off shore plastic turn signal assembly. Carefully manipulate each wire to those circuits while an assistant stares at the amp meter and if the draw goes away for a second the assistant yells, stop and you don't move your hands and stare at what do moved. A D-Arsonval meter is best used for this as the digital tend to flash and is not as clear to see as a needle drop. Good luck

 

[B RON CO]

Hi, just for kicks I would change the flasher. If it is crapping out it may cause more current draw. I would also clean each bulb socket and go over the grounds to minimize resistance. Do you have regular old fashioned 1157 bulbs, or some high draw halogen thing in there? Good luck

 

[nickgp]

And make sure you have sufficient grounding. Engine, body , chassis.

 

[DirtDonk]

Where does it melt exactly?

Paul

 

[CA10Cruzer]

you have replace the whole switch or just replaced the canceling cam part? 4 times

 

[pcf_mark]

As Dirt Donk noted where exactly it melts could be very helpful.

Also what else did you do 4 months ago? New radio? Add some driving lights?

Are these all the same brand melting? When new do all the functions work?

 

[Rustytruck]

Did the melting part happen after the first time you replaced the turn switch or was it the reason it failed the original switch? (IE making a mechanical problem into an electrical one) Do you have any trailer wiring? if so you might want to check for a wiring short there.