Technical bulb failure warning light

[digger58]

Hi all,
The warning light came on today, sure enough left rear tail light blown, replaced bulb but warning light is still on, all other bulbs working, any ideas please,

 

[T14086]

wrong bulb wattage

 

[Ziggy122]

usually wrong bulb if you fit a 5w and it should have a 10w bulb in it - the car picks up on that

Also A Over Corrodded Earth Pin can cause this too - Does one light look stupidly dim? or a Another Light activated?

Ziggy

 

[digger58]

Definitely right bulb, checked that already, perhaps it's like the Ulysse, need to reset the system now and again, I usually do this every now and again to resolve lots of warning lights, it resets the body computer. any other suggestions please?

 

[T14086]

were not talking about bulb type but the wattage rating, is that correct?

 

[Ziggy122]

Just because the bulb is right shape/size/poles doesn't mean its the correct one

The Wattage and voltage rating are also important

Ziggy

 

[Brin]

The wattage is printed on the bulb most of time check it im sure u need a 5w for rear sidelights not 10w

 

[Ziggy122]

The wattage is printed on the bulb most of time check it im sure u need a 5w for rear sidelights not 10w

otherway around
Manual states Rear Tail-lights are 10w
Brake - Reverse - fog - and rear directionals 21w

Ziggy

 

[digger58]

As I said in my previous post DEFINITELY RIGHT BULB both wattage and fit!!!!!, I disconnected battery this am and spent the day in the X1/9, will try again in the morning to see what happens. Last week the engine management light stayed on for a day after I had replaced the cooling fan motor, righted itself so I am a little suspicious that it's like the Ulysse.

 

[Ziggy122]

If the Bulb is definatly a 10W and a Single Bottom Pole then its going to be another light or a bad earth

Ziggy

 

[digger58]

Connected up this morning and all OK, must be storing a fault in the system. Whatever, battery disconnect works for me.

 

[Ziggy122]

Connected up this morning and all OK, must be storing a fault in the system. Whatever, battery disconnect works for me.

it doesn't store a fault
Nore will it produce a fault code

its a simple circuit that see's the voltage and Current - when it doesn't meet within range
it brings the error light

Bulb out = current low = Error
Bad Earth = Low voltage + low current = Error

Ziggy

 

[digger58]

Thanks for that Ziggy, but it doesn't explain why a disconnect sorted the warning light, nothing else touched, why would changing the cooling fan motor do the same or is that stored as a fault?, I don't think so as the old one was kaput and no warning was showing. Is my car possessed? Damien may have been the previous owner!