Which Rear Bulb to Change?

[hotlips69]

On my left rear light cluster, the light at the top of this cluster which stretches most of the length has stopped working.
This is not a brake light or reverse light & comes on as soon you start the engine on the other side of the car.

Every other bulb correctly lights.

I know there are 3 replaceable bulbs, but don't know which of these is the one I need to replace as I can't find any picture/diagram indicating which bulb lights which area? :x

 

[Pondrew]

This is not a brake light or reverse light & comes on as soon you start the engine on the other side of the car.

Come again?? :?

 

[hotlips69]

I was merely trying to explain which light was not working, so someone can help me work out which bulb I need to replace.

Its the light at the top of the cluster, which comes on as soon as you start the engine.

 

[B21]

That’s an LED built in..you’ll need a new unit or use the eBay guy that refurbsvthem..

 

[hotlips69]

That’s an LED built in..you’ll need a new unit or use the eBay guy that refurbsvthem..

I thought the only LEDs is the indicator strip at the bottom of the unit??

 

[B21]

That’s an LED built in..you’ll need a new unit or use the eBay guy that refurbsvthem..

I thought the only LEDs is the indicator strip at the bottom of the unit??

No both tail light and indicator LED based which are not user serviceable..brake lights and reversing lights use conventional bulbs..

 

[hotlips69]

Thanks for the info.

This query is based on a brand new unit I purchased from autodoc & installed yesterday:
https://www.buycarparts.co.uk/magneti-marelli/1855704

Is a "tail light" the large light strip at the top of the cluster as this term seems to be used differently, including meaning the indicator LED strip?

 

[Chippie]

Tail light is generally considered to be the red light that shows when you turn your cars lights on (if they don’t come on automatically when you start the car)
The white/clear strip at the bottom is the indicator (orange when flashing)

 

[Kevin]

This query is based on a brand new unit I purchased from autodoc & installed yesterday:
https://www.buycarparts.co.uk/magneti-marelli/1855704

If it's a new unit and the LEDs don't illuminate, then either it is faulty or you have a problem with the electrical circuit, of course.
If you have a multimeter, you can probably figure out if power is being supplied. It could be as simple as a loose or dirty connector,
so that would be the first thing to try. Was it working before you replaced it?

With typical usage patterns on these cars, I'd expect an LED to last 20 or more years, but there can always be poor solder joints
or other problems.

 

[Kevin]

Is a "tail light" the large light strip at the top of the cluster as this term seems to be used differently, including meaning the indicator LED strip?

Yes, on the Z4 it's the red LED strip across the top, which is on when the other lighting is illuminated

 

[hotlips69]

If it's a new unit and the LEDs don't illuminate, then either it is faulty or you have a problem with the electrical circuit, of course.
If you have a multimeter, you can probably figure out if power is being supplied. It could be as simple as a loose or dirty connector,
so that would be the first thing to try. Was it working before you replaced it?

The original unit had the usual water ingressed indicator issue, but every other light in the unit was working perfectly.
I'm not technical & don't own a multimeter, so I've requested a return/replacement of the unit.