Hi Chris,

I am working on a 1980 Fiat Spyder. Can you think of any reason that the headlights would come on when the ignition switch is turned on regardless of the position of the head light switch?

It has been wired that way? The switch has failed on??

The customer did not want to go for the needed lense and bulb holders/pc boards, so he is having me wire in individual light assemblies and then custom fit them himself. Go figure. I have mounted 3 assemblies. One for turn only, one for backup only and one for tail and brake lights.

Upon checking each wire for power to the proper bulbs I wired the new assemblies as such. Very basic, I think, but I did notice as I was checking wires sometimes the head lights would be on and sometimes not. Now the headlights are on any time the ignition is turned on. This may be a problem when starting in cold weather.

Could it be that a headlight relay is going bad?

What headlamp relay? The factory never installed headlamp relays. However, if you are installing any new Halogen or other "modern" headlamps in an old Fiat, I highly recommend that you wire the car so all the car's wiring does is turn on the head lamp relays you install which control their own circuits that you also install!

Does this car have one?

Not unless you or someone else installs them.

Or are there diodes in the pc board which I have eliminated causing feed back?

Nope.

Or is it just my bad luck that something went bad like the headlight switch, just when I got to work on the vehicle. I am sure you know the feeling.

Yep, God shits on us in interesting ways. I have determined a long time ago that I am not responsible for acts of God. UPS agrees.

Any help is appreciated. I do not see any connection with what I did and the headlights coming on with the ignition switch. Thank for your help

Jon Elwell

I don't either, so now all you've got to do is convince your customer! Good Luck!