LED bulbs (tail lights) - brake lights always on

[JulesT]

Hi all,
It's a mysterious one but hopefully there is someone out there with a little more understanding on this subject.

I have LED tail light bulbs purchased online from America which I used on a Ford Focus mk1.
I fitted them on my Leon, turned the key, tried them (switched lights on/off, then brake lights etc.) and they worked fine... but when I started the car up, the brake lights were on permanently.

So my question is, would canbus LED bulbs resolve this issue?

 

[hyphon12]

Have you tried refitting the standard bulbs to see if its definitely the bulbs? as it might be the brake light switch fault. CanBus LEDs shouldn't make a difference as the Mk1 Leon doesn't use CANBUS.

 

[LEE69]

Mk1 leon does not need canbus leds.

 

[JulesT]

Thank's for your responses guys.
Yes, the normal bulbs work fine. So it may be a fault with the LED bulbs then. I also have a pair of cheap crappy ones, I will try them once I get my car back.

 

[LEE69]

can they be fitted 180 deg out. are the pins opposite?

 

[JulesT]

It's not possible with that type of bulb as one pin is higher than the other.

Also they were working properly before I turned the engine on.

 

[hyphon12]

Might need a resistor put in? as it might be due to a small current that's flowing though the circuit that isn't enough to power a standard filament bulb but is enough for a LED?

 

[nd-photo.nl]

Hmm I checked mine and same behaviour. Im running with Powerflux leds and my 3rd brake light is on (very dim) when my lights are on. I passed MOT though, guess they didnt see it...I swapped 1 led for halogen and then its fixed. So it needs resistors to work properly

 

[LEE69]

My 3rd brake light glowed feintly when i had the led rear lamp/clusters.I kept it as it was quite cool, and passed mots fine, went brighter when pedal was pressed.

 

[gdjohny]

Yup
Same story here
Third stop is on all the time with lights turned on but it looks cool for me

 

[JulesT]

So this is the reason I asked about canbus bulbs.
I don't want to fit resistors because of the heat they will produce, whereas canbus bulbs have the resistors built in ...if I'm correct

 

[JulesT]

Update: LED tail bulbs

So I tried the cheap bulbs I have and they worked fine, but they caused the glow plug light to constantly flash. So I took them out and put the original bulbs back.

This is what they looked like:



So I bought some nice bright 50w cree bulbs, but like the previous ones, they came on by themselves when I started the engine and they got very bright when I actually turned on the headlights.

This is what they look like:



So I think I need resistors, but because there are 2 wires plus earth, will I need 2 resistors each side?