No Headlights

[bairohio]

I mentioned this one before. Bought car. No headlights. Running lights, turn signals, brake lights all seem to work just fine but no headlights.

1980 spider.

not getting power for headlights at the fuse box, none at headlight (obviously). Not sure where to check next. Pulled the light switch itself but I wouldnt know how the check that and frankly it looked to be in good shape.

I am lost as to what to do. I even pulled the steering wheel thinkging perhaps a wire had come loose. Nope.

Suggestions?

[Rambo]

Have you tested voltage at the headlights? A voltage meter is your best friend when diagnosing electrical problems. Look at brads wiring diagrams so that you can understand the system and you have to just diagnose by looking at wires, connections, and testing voltage back to where you find power to find out at what point the problem occurs.

http://www.artigue.com/fiatcontent/Wiring_1979_1980.pdf
This is for the carb spider

http://www.artigue.com/fiatcontent/Wiring_1980_1982.pdf
This is for the FI spider not sure what you have.

[vandor]

the most likely culprit is the headlight switch. From the wiring diagram you can figure out which wire is hot and which one goes to the column switch (where it is switched to either low or high beams). Jump those two. If the lights come on them the switch is bad.

[VAspider]

I had the same issue a while back after a drive. I did have the flash to pass function working so I was able to tape the two levers together to get home. If the lights come on using that function, pull lever towards you. Then you most likely have a bad switch, no lights trying that is probably a power source problem.

[aevansgatech]

I had the same conditions of working turn/running lights and no headlights. Turned out the switch was the culprit, but it was completely fixable.

Take it apart and make sure the contacts are in line. One of my internal "rocker contacts" had flipped onto its side and wasn't making contact in the full headlight on position

Good luck!

[bairohio]

Thank you all, a lot of useful info. This board is truly a great resource.

The switch, is this a common part I can pick up at the auto store or do i need to order something Fiat specific?

[vandor]

Fiat specific.

http://www.autoricambi.us/product/EL7-4 ... --1972-82/

[bairohio]

Well as it turns out it goes beyond the switch. I am now on 2nd replacement switch with same outcome. I removed swith as well as the wires in the plastic connector piece between harness and switch. With different wirings configs at switch i can get headlights and running lights or just running lights. Thing is that with the headlights and running lights working i then have no wipers!

Ok..should the wipers in any way be tied in to the light switch? Thoughts?

[vandor]

The headlights should not be tied to the wipers. Both go through the ignition switch, tho. It's a possibility that they go through the same contact in the ignition switch (I am not sure, there are 2 contacts in there that distribute power to the car) and that contacts is faulty and can only pass so much current.
It is possible you jiggled something else loose related to the wipers while working on the headlights. Oh, and remember that Spider wipers get really slow, and sometimes there is so much friction in the linkage that the wipers won't even start if the windshield is dry. So try the wipers with them flipped up, and also try both speeds (round switch in middle of dash).

[spider2081]

Looking at just the headlight switch operation. the headlight on/off switch is a 3 position switch.
Up is off
Middle is parking lights and license plate lights
Down is headlights.

The middle position is fed power from an unfused black wire that is "hot all the time". This wire also supplies power to the inline fuse for the cigar lighter.

The down position Is fed power from the unfused light blue wire. This wire originates from the "INT" contact on the ignition switch. It has power in the "Run & start" positions of the ignition switch.

The headlight on/off switch is internally made such that when in the up (off) position the black wire and the light blue wire contacts are not switched to any other contacts. When the switch is in the middle position, The black power wire is switched to make contact with the white/black wire. This will light the parking lights whether the ignition switch is on or not. Moving the headlight switch to the down (on) position, disconnects the black wire from the white/black wire. The black wire is not used when the headlight switch bat is in the down position. The light blue wire now supplies power to both the parking lights through the white/black wire and the headlights through the Green wire. The green wire is connected to the hi/lo beam switch on the steering column. The lo beam switch output is on a Gray/red wire that feeds Fuses 5 &6 The hi beam output is on the dark blue wire that feed fuses 3&4.

Try make in some tests with a volt meter or test light and let us know what you find.
Do you have voltage on the black wire at the headlight switch when the cars battery is connected
Do you have voltage at the light blue wire on the headlight switch when the ignition switch is in the "Run" (on) position.
Do you have voltage at the fuses 5&6 when the column switch is in the lo beam position? Ignition switch on
Do you have voltage at fuses 3&4 when the column switch is in the hi beam position? ignition switch on

[spider2081]

Forgot to mention. Some of the replacement column switches have a 3 position headlight switch. full up is off middle is lo beam and down is hi beam. The stock column switch had only 2 positions up is lo beam and down is high beam.

[scubachris]

Looking at just the headlight switch operation. the headlight on/off switch is a 3 position switch.
Up is off
Middle is parking lights and license plate lights
Down is headlights.

The middle position is fed power from an unfused black wire that is "hot all the time". This wire also supplies power to the inline fuse for the cigar lighter.

The down position Is fed power from the unfused light blue wire. This wire originates from the "INT" contact on the ignition switch. It has power in the "Run & start" positions of the ignition switch.

The headlight on/off switch is internally made such that when in the up (off) position the black wire and the light blue wire contacts are not switched to any other contacts. When the switch is in the middle position, The black power wire is switched to make contact with the white/black wire. This will light the parking lights whether the ignition switch is on or not. Moving the headlight switch to the down (on) position, disconnects the black wire from the white/black wire. The black wire is not used when the headlight switch bat is in the down position. The light blue wire now supplies power to both the parking lights through the white/black wire and the headlights through the Green wire. The green wire is connected to the hi/lo beam switch on the steering column. The lo beam switch output is on a Gray/red wire that feeds Fuses 5 &6 The hi beam output is on the dark blue wire that feed fuses 3&4.

Try make in some tests with a volt meter or test light and let us know what you find.
Do you have voltage on the black wire at the headlight switch when the cars battery is connected
Do you have voltage at the light blue wire on the headlight switch when the ignition switch is in the "Run" (on) position.
Do you have voltage at the fuses 5&6 when the column switch is in the lo beam position? Ignition switch on
Do you have voltage at fuses 3&4 when the column switch is in the hi beam position? ignition switch on

Ok so the car passed the first and second test but I am not sure if I am doing the last two test right. How do you test voltage at fuses? Do you put the red on the top or bottom?

[spider2081]

Ok so the car passed the first and second test but I am not sure if I am doing the last two test right. How do you test voltage at fuses? Do you put the red on the top or bottom?

The meter black lead connects to a known good ground. Like the ground pod behind the ignition switch.

the red wire connects first to the top of the fuse ( this tells you if the fuse is getting voltage to it) then move the red wire to the bottom of the fuse. THis tells you if the fuse or contact are bad. You should have voltage on both ends of the fuse.

[scubachris]

Ok so the car passed the first and second test but I am not sure if I am doing the last two test right. How do you test voltage at fuses? Do you put the red on the top or bottom?

The meter black lead connects to a known good ground. Like the ground pod behind the ignition switch.

the red wire connects first to the top of the fuse ( this tells you if the fuse is getting voltage to it) then move the red wire to the bottom of the fuse. THis tells you if the fuse or contact are bad. You should have voltage on both ends of the fuse.

Ok so I tested the black and it had power, I tested the blue with the car running and it had power. I have no power going to the the fuse box on top while the car is running. This might be a stupid question but does the switch need to be connected to get power to the fuse box? It wouldn't seem so but I'm not really sure. So what should be the next step?

[spider2081]

Between the headlight on/off switch and the fuse panel is the headlight hi/lo switch on the steering column. The original hi/lo switch was a 2 position either hi or lo beam. Some aftermarket replacement switches have an off position. Full up with the lever is off middle is lo and down is hi beam. Also there is a headlight flash switch that is activated by pulling the lever toward you. It is common for the column switch to fail over time especially if higher wattage headlight bulbs have been installed.