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Technical No brake lights without ignition?

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Technical No brake lights without ignition?

Piccolo Nero e Bella

Piccolo Nero e Bella

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I seem to learn something new about my Fiat every day. It seems the brake lights will not function unless the ignition is on (yes, I've just discovered this after 12 months ownership!:eek:). I can say with confidence I've never known a car in which the brake lights would not come on with every press of the pedal, regardless of the state of the ignition. Is this a European norm?

PS; or could it indicate a fault?
 
Sadly in my Subaru the horn works when the ignition is off, I slept in my car rather than pitching a tent and honked the horn at 2 in the morning, the hundreds of people on the campsite were very amused....
 
Piccolo Nero e Bella said:
I seem to learn something new about my Fiat every day. It seems the brake lights will not function unless the ignition is on (yes, I've just discovered this after 12 months ownership!:eek:). I can say with confidence I've never known a car in which the brake lights would not come on with every press of the pedal, regardless of the state of the ignition. Is this a European norm?




The question is why would you want the brake lights to work if not driving the car ? If you want to just check the lights are working ok just turn on the ignition without firing up.
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Saab brake lights used to work without ign, at least all the 95/96 range, and I think the 99s too. Something to do with towing I seem to remember. They also had an ignition key that locked the transmission into reverse rather than the steering.
 
123barney said:
The question is why would you want the brake lights to work if not driving the car ?
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Turning your question on its head, why not? It's not as if you might forget and leave them on. What I'm trying to understand is the reasoning behind controlling the brake light circuit through the ignition - it adds a layer of complexity to what has been a very simple, and therefore reliable, circuit; battery-fuse-switch-light. What are the advantages?
 
Piccolo Nero e Bella said:
Turning your question on its head, why not? It's not as if you might forget and leave them on. What I'm trying to understand is the reasoning behind controlling the brake light circuit through the ignition - it adds a layer of complexity to what has been a very simple, and therefore reliable, circuit; battery-fuse-switch-light. What are the advantages?
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If the switch fails then you don't flatten your battery.
 
Piccolo Nero e Bella said:
Turning your question on its head, why not? It's not as if you might forget and leave them on. What I'm trying to understand is the reasoning behind controlling the brake light circuit through the ignition - it adds a layer of complexity to what has been a very simple, and therefore reliable, circuit; battery-fuse-switch-light. What are the advantages?
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Basically it's good engineering practice to isolate electrical circuits when they don't need to be live.

It gives an additional layer of protection in the event of a fault.

In days gone by, it wasn't unusual for brake light switches to fail in the 'on' position.
 
jrkitching said:
Basically it's good engineering practice to isolate electrical circuits when they don't need to be live.

It gives an additional layer of protection in the event of a fault.

In days gone by, it wasn't unusual for brake light switches to fail in the 'on' position.
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I would say brake light working with IGN off is more safety driven than engineering etiquette. A dead short in the IGN or something causing a blown IGN fuse while driving will allow for brake lights to keep functioning. Similarly on many cars the headlights will also keep working which would be pretty handy at night.
 
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logger said:
I would say brake light working with IGN off is more safety driven than engineering etiquette. A dead short in the IGN or something causing a blown IGN fuse while driving will allow for brake lights to keep functioning. Similarly on many cars the headlights will also keep working which would be pretty handy at night.
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A dead short in the IGN circuit and you won't be going anywhere.
 
jrkitching said:
A dead short in the IGN circuit and you won't be going anywhere.
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I very much suspect you will, if it occurs when you are driving. The first thing you are likely to do when it occurs at highway speed or any speed for that matter is apply the brakes and bring the car to a safe stop. Would be very handy for other drivers behind you to know your intentions by way of operable brake lights, that do not rely in the failed/shorted IGN to work. If it happened at night would be most convenient if your headlights did not rely on the IGN circuit to function as well.
 
logger said:
I very much suspect you will, if it occurs when you are driving. The first thing you are likely to do when it occurs at highway speed or any speed for that matter is apply the brakes and bring the car to a safe stop. Would be very handy for other drivers behind you to know your intentions by way of operable brake lights, that do not rely in the failed/shorted IGN to work. If it happened at night would be most convenient if your headlights did not rely on the IGN circuit to function as well.
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You have got far more chance of having a tyre burst, than a very rare IGN short, imo.
 
logger said:
I very much suspect you will, if it occurs when you are driving. The first thing you are likely to do when it occurs at highway speed or any speed for that matter is apply the brakes and bring the car to a safe stop. Would be very handy for other drivers behind you to know your intentions by way of operable brake lights, that do not rely in the failed/shorted IGN to work. If it happened at night would be most convenient if your headlights did not rely on the IGN circuit to function as well.
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That's more or less what I was thinking, just better expressed. I've also never had a car in which the headlights were controlled through the ignition...
 
Piccolo Nero e Bella said:
That's more or less what I was thinking, just better expressed. I've also never had a car in which the headlights were controlled through the ignition...
Click to expand...

Many cars these days will allow you to turn the headlights on for test purposes, but once ign is on, turning it off will extinguish the headlights, leaving sidelights and tail lights on. The headlights come back on when the ign is turned on again. Makes the battery last longer before it goes flat. If you stall, turning the key off, then on again to restart will keep the car illuminated. With the Fiat however, turning the key off to restart turns all the lights off, could be quite nervewracking when we used the 500 as a school car in the winter evenings. The Fiat system prevents you leaving the lights on accidentally.
 
Piccolo Nero e Bella said:
That's more or less what I was thinking, just better expressed. I've also never had a car in which the headlights were controlled through the ignition...
Click to expand...



What sort of cars have you owned?

I've owned a Fiat 131, Peugeot 504, Peugeot 406, Fiat 500, Fiat Panda and a Subaru Legacy and only the Pugs have enabled you to leave the lights on. Have a guess which two cars have left me stranded with a flat battery?
 
I only noticed this in the vw caddy and hadn't noticed in the fiat cause I'm so quick to put foot on brake and turn ignition on... Other cars have never done this for me either.
 
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