Heater Control Knobs - how to 'illuminate'

This 'How to' uses the Mk2 knobs(black and grey) But will work with the Mk1 knobs also.



I have always found it difficult to see which end of the controls was the one with the 'black dot pointer' when driving.



This means that sometimes you have to rotate the knob both ways to figure it out. I think that sometimes the controls are broken because of this.

I thought what we need here is a more prominent method of denoting the pointer.

Soooo, I found some old 5mm clear leds,




and snipped the legs off.



Using the black dot as a start point



I drilled a hole through the heater control, sized to be a neat fit on the led (be aware that 5mmm leds are actually about 4.7mm diameter)



I then cleaned out the swarf from the knob





and inserted the led from the inside of the control,




and pushed it through so that it protruded a few mm. I added a few drops of clear glue to hold the led in place.



The control knob now looked like this.







Repeat twice more with the remaining heater controls.



Now it is easy to see which way the knob is pointing!

And why did I use old clear leds?

Because if you look at the grey background that the three control stems fit through, (the one with the switch position markings on) you will see that it is a plastic sheet, covering the clear screen of the light box.

If you remove this sheet and enlarge the holes, making sure to keep the new holes smaller than the knobs.( You will probably be able to see a definite circular mark on the sheet caused by the rotating knob - cut your new hole 5mm smaller than this marked circle) To do this you will need to remove the centre console fascia.

Now when the instrument illumination is on, sufficient light will escape into the back of the knobs to show through the leds, and so the new led pointers are gently illuminated at night!

Tadahh!
David more pics to follow.

Fantastic guide David - looking forward to seeing pics of them in the dark. 10/10 for ingenuity! :thumbsup:

Yves Adele Harlow;2204 wrote: Fantastic guide David - looking forward to seeing pics of them in the dark. 10/10 for ingenuity! :thumbsup:

Piccies coming!

David Aiketgate;2217 wrote: Piccies coming!

I used this fantastic guide, very easy and took about 15 minutes. Most likely due to the angle of the rear of the leds not much light was 'escaping though. Luckily having access to some small right prisms, so i glued one to each of the rear of the leds using UV glue.



Changes the angle of the light entry and now channels the light really well



Now I'm going to glue coloured filters on the back of the prisms, just can't decide what colour...
red
blue
green
dark orange
??
might go for red on the central heat control and green on the other 2...
.. I think I might start obsessing over this!

Great tip Tim. It compliments the original guide so well that I've added it to it. Keep us posted with your future pics here too please.

I tried this one myself but messed it up. I'd be interested in seeing some intricate close up pics of your prism mod, if possible.

Great to see this idea is still being used and improved on!:broon:

Good how - to ,
I am just about to do this and I'm going to attempt to use red LED to compliment my radio backlight .. will report back
The bulbs in heater controls look enormously difficult to replace should they fail, so I have taken the opportunity of replacing them while I have this level of disruption

Brilliant little Improvement ,this can be done quite neatly to if you follow your instructions,👍👍
However ,I found but my first attempt did not generate enough light through the illuminator , so I think I have made a little little improvement by drilling through a little further round the radius of the switch....? see photographs