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Discussion Starter #1
I've got a (new to me) 2013 Fiat 500C and I'm at a loss for why the headlights (both high and low beams) do not work consistently.
They often flicker on and off and occosionaly stay on but often decide to not work. There's no consistent pattern. All other lights and electronics on the car function normally.
After much reading on this forum I assumed the headlight switch was faulty. I went ahead a replaced the switch which is integrated with the clock-spring and turn signal stalk, but no help. Same issue. An expensive part but no help.
I've looked at the fuses and replaced both headlight bulbs. No help.
Any ideas? I'm in the dark.
thanks for any insight
 

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Might be a software issue, with the BCM. Run it by a Fiat dealership, have them reload the software on your car. That controls the headlamps. Might be corrupted. Software runs everything, on modern cars.

Good Luck.
 

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+1 on smark's suggestion... easier than the BCM.

Headlights on a US model 500 are single filament. (You'll hear a "snick" as the shutters pull back, exposing the top half of the bulb, when you turn on high beam.)

The problem can be in the BCM (Body Control Module). There are 2 small relays soldered to the board that operate the headlights. Like all relays, they can eventually fail, either welding themselves closed (lights stay on all the time) or carboning (lights don't come on reliably). From reading, if the BCM is replaced, it must be "registered" with the system.

There are several videos on Youtube showing how to remove the BCM and the location of the relays. This video shows what's involved in replacing the relays on a 2013. If the same BCM is inserted back into the car, the car will recognize it.

This guy had your problem and found it was cold solder joints. (4 parts, but he doesn't show taking the BCM boards apart.)
 

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Discussion Starter #4
Thanks much for the advice. I'm hoping that it's not the BCM as it's a very expensive part. I have tapped on the location of the BCM when the lights have been activated, but I've not seen any change to the continuity. I'd expect some flickering or change of performance if there was a loose solder or wire. Hope there's another possible fault.
If I understand Smark's comment, it's worth having the dealer simply reload the software to see if this resolves the problem?
 

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Yeah, we still have some electronics repair shops in town and I think a couple friends still do it as hobbies. If mine goes awry, and I don't fix it myself, I have sources. The pair of relays are about $8, per the video.

That's a major design flaw, IMHO. $3 for sockets vs a $1000 repair... but it's typical.
 

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Discussion Starter #6
Thanks for the input. I will see if the dealer will reinstall the software before I commit to changing the BCM. The flickering and occasional on and off of the headlights isn’t quite the same as the noted ailments from other posted comments, where they have had an issue of always on or always off. Hope the software makes a difference.
 

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I had same issue until the lights just stayed on....in the end I ordered new relays, destroyed the old ones on the board, but left the pins sticking up. Soldered wire to the pins and the new relays....

After talking to an aftermarket programmer, he said to seperate the 2 boards in the BCM with a pin removal tool (never heard of). The back board contains your vin encoded stuff, the front board your relays. Once you get them seperate, replace the front board with one from junkyard (should snap back together) or resolder your relays.... But no programming required if you keep the back board...
 

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Discussion Starter #8
Thanks Scott, good information. Interestingly my BCM has moved to the next faze as of this week. The headlights do not turn off at all now. I can’t understand how having the relays stuck on would keep the headlights on even after I shut off the car and take out the key. Shouldn’t the ignition shut everything off? Maybe it’s the “coming home” function that’s triggering the lights but that seems like an issue of the software and not the relays. Wonder if it’s a simple process to have the software reflashed before I commit to a new BCM.
Thanks again
 

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Discussion Starter #9
Quick question for anyone who might know, is there a reason why I can’t just bypass the BCM integrated relays for the headlights by splicing the wires from the headlight switch stalk to a separate set of relays outside of the BCM? Why bother changing the relays in the BCM if it can be bypassed all together?
 

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I don't see why you couldn't wire them up like people do with auxiliary truck lights. Light relay kits are sold on Amazon for under $20. It will be easier/safer to bypass the stalk and use the provided on/off switch. Of course, you'd lose the automatic functions the BCM provides, auto-shutoff and dimming the DRLs when headlights are on.

If you watch the 4-part video, he has exactly your condition... lights stay on all the time. He found his had bad solder joints. To me, that indicates it is a latching relay.
 
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