Ignition switch connector gets very hot

[Tobi]

Hey everybody, I had my 81 FI for three years now and I am on the fourth ignition switch. That is maybe because I used two IAP Lada switches and a $20 cheapo from ebay. For the last year it was actually a Home depot light switch on a 10 gauge wire for the ignition. It has been working fine but a few weeks ago the ignition switch connector got very hot and even smelled burned when I had my lights on. I have a used original 81FI switch laying in my shelve now and did not want to burn it so I did not install it yet.
Is the Home Depot switch my problem or do I have a ground problem some where? My blinker also slowed down a lot lately, specially when I had my lights on and/or the motor was idling (Alternator?). Also my starter (new) sometimes turns very slow.
Is there a connection or do I have three different problems?
Any thought would help here.
Thanks, Tobi

[manoa matt]

You had a good idea not to burn up the good original switch until you get it figured out. The problem is the original wiring routes a lot of power through the switch and the contacts eventually burn out.

There are two procedures that you can do to take the load off the switch. Do some searches for "brown wire surgery" or "brown wire fix" This fix brings a fresh 12V to the switch. The second is the "headlight relay upgrade" This fix introduces 2 relays to switch the power source from the switch to the alternator or starter, thus taking the load off the switch.

[Tobi]

Thank you Matt,
that is kind of what I expected I just did not know what to search for. I printed out the brown wire surgery and the headlight relays thing I found here and will get the wires and relays today.
Should I skip the ignition switch plug with the additional brown wire and go straight to the switch. That would make replacing the switch harder but maybe it would be worth it in order to have a stronger connection. I hope after fixing that I will never have to replace the IS again.
I hope the relays set up for the head lights will finally bring enough power to the halogens (H4) I bought in Germany two years ago and still look like candles.
I think I will also check on all the ground connections on the car.
Please everybody let me know if you can think of any other improvements that could help.

[Tobi]

OK, I just found an older post where it said that the FI models already have the brown wire fix.
I am starting to think that it could be a lose connection in the Ignition switch connector and the ground connections and the head light relays, of course.
Otherwise I am still looking for clues.

[Tobi]

Hey, it's me again. Well at least I keep my topic on top of the list.
I got one more question here. When I do the relays set up for the head lights, shouldn't there be a fuse in between the relays and the head lights?

[So Cal Mark]

I put the fuse in the power wire between the power source and the relay. That way the whole circuit is protected

[Tobi]

Thank you Mark, I will do that.

I got my main problem fixed by simply replacing the ignition switch (I don't understand but what ever). The second test drive ended on a AAA flatbed with a non working fuel pump. Back in my garage I tried another switch, nothing. I plug back the new switch and it run a minute after AAA left. I was playing with that plug the whole time I was waiting for AAA and nothing. Also, everything worked but the fuel pump.
I am just going to have a lot of tools and parts in the trunk for my next test drive.
Damn I love that car, hate the car, love that car........

[kathyfiat]

Hello Fiat Spider enthusiasts. I have a 1980 Spider and just had the original ignition switch rebuilt, added new headlight relays powered off the alternator, and added the brown wire fix to the ignition switch. The car seems to run fine and the headlights are nice and bright now but the ignition switch seems to run very warm -probably 110 degrees. My white switch connector was removed and all wires crimped together. Does anyone know what the operating temperature of the ignition switch should be??
Thanks
Bill Ante