I don't know if it is a coincidence and I can't remember if they came on before changing them, but replaced side lights with LEDs and the fogs no longer come on. Switch is all powered ect. Even dropped it into a garage and they couldn't see anything wrong. I also swapped out the fog bulbs.
Could fitting LED sidelight bulbs cause foglights to not come on?
- Thread starter Ilogik
- Start date
Attleborough, Norfolk
Ah, I didn't mean they needed registering. I only meant the foglights only switch on once the sidelights are on.Ilogik said:enuff_zed said:
Will order some new bulbs, that's handy to know about needing to register the sidelights. As all my switches have power but nothing on the fogs. Will report back.
I was wondering if perhaps the 'error-free' element of the LEDs was causing the LCM not to realise they were switched on. But then surely it would go by the switch position?
Second guessing myself now. :roll:
I'll chip in with some observations:
'Error free' LEDs defeat the primary object (imho) of lower power consumption and longer lifespan. There is nothing smart about them, they just add a load resistor to draw the same power as a halogen bulb. Car doesn't sense anything different so no bulb warning triggered. But the tiny little package (oo-er) now has to dissipate extra heat leading to failure before an equivalent bulb.
The 'proper' way to do it is to buy decent brand (e.g. Osram/Philips) LEDs and code out the blub checks. I've got LEDs that are coming up on 10 years old that are still going strong.
IIRC fogs should only come on with at least sidelights. I would imagine (but can't see in the wiring diagrams) that this is controlled by switch position, as it shouldn't matter if the sidelight bulbs are out.
I don't have front fogs fitted but the car still sends the signal to turn them on.
So LEDs in any position shouldn't matter and it seems like coincidence. I can dig out the pinouts if you want to try a multimeter on the LCZ.
'Error free' LEDs defeat the primary object (imho) of lower power consumption and longer lifespan. There is nothing smart about them, they just add a load resistor to draw the same power as a halogen bulb. Car doesn't sense anything different so no bulb warning triggered. But the tiny little package (oo-er) now has to dissipate extra heat leading to failure before an equivalent bulb.
The 'proper' way to do it is to buy decent brand (e.g. Osram/Philips) LEDs and code out the blub checks. I've got LEDs that are coming up on 10 years old that are still going strong.
IIRC fogs should only come on with at least sidelights. I would imagine (but can't see in the wiring diagrams) that this is controlled by switch position, as it shouldn't matter if the sidelight bulbs are out.
I don't have front fogs fitted but the car still sends the signal to turn them on.
So LEDs in any position shouldn't matter and it seems like coincidence. I can dig out the pinouts if you want to try a multimeter on the LCZ.