Heater Lighting

People often have trouble with the heater lighting, either not being sure if it's back lit at all
or having serious issues understanding where the bulbs are and how to access them.

The confusion is fair enough because the single bulb is hidden fairly well.
It's actually hidden inside the dash top button bank and it requires some work to get to the bulb.

1 Single Bulb? Really!

Yep, it uses a plastic light pipe to distribute the light all the way around and behind the heater symbols.

Removal From The Car

Lever the unit out of the dash with a flat blade screwdriver. 

Roadster

This is a typical Roadster 4 button layout, this one is from a Brabus.



Remove the Torx 8 screws circled in red.



Remove the black cover.



Lift the PCB from the surround...



...and flip it over.

The bulb is usually beige or orange and can be removed with a 1/4 turn.



Removing The Bulb

The easiest options are to use a 6mm socket or a flat blade screw driver.
Twist it a quarter turn in either direction and it will be free from the PCB.

Refitting A Bulb

Place the new bulb into the hole and twist it a quarter turn anticlockwise.
If you are fitting a standard bulb, it should work no problem.

If you are fitting an LED, if it doesn't light, twist the bulb 180 degrees so the contacts swap over.
Don't expect good results when using LEDs as the light pipe is not designed to them.

What Bulb Do I Need?

They are actually tricky to buy because most sellers prefer to sell LED replacements.
However, with the right search word, you can easily find them on eBay.

Look for Osram BX8.4D and decide on the base colour you want.



The beige base is 1.5 watts and the orange base is 1.1 watts.



So, the beige base will be brighter which is far better for the heater lighting.

You can also get 2 watt versions of this bulb. I haven't tested them personally.
If you do try the 2 watt version with the pale green base, check after a while to make sure nothing is melting.