850 Phase 1 Dash switch bulb relacement tutorial
 

Today I set about replacing around 6 of my Dash lights as they never lit in the dark

so here is a tutorial

First, purchase some replacements from MAPLIN, the code for them is BT43
they are 12v 60ma bulbs. They are different in size, but they work just the same

here is a comparisson shots

http://ukmil.hopto.org/images/850/sw/11.jpg

Firstly, you will need
replacement bulb
Small scredrivers
Snips
Soldering Iron and Solder

http://ukmil.hopto.org/images/850/sw/1.jpg

First task is to open the switch. the switch is split in half, with this one, you can see the BLUE back half. Other switches may be yellow, white, or black. The halves are held together by notches. there are 4 of these, one on each side, as you can see here

http://ukmil.hopto.org/images/850/sw/3.jpg

use the screwdrivers to prize open the switch. Be CAREFULL not to snap the latches, as the switch will not work when you put it back together

http://ukmil.hopto.org/images/850/sw/4.jpg

once you have the switch uncliped. do NOT just prize it open as there are loose parts inside. Place the switch down like this and lift the top off

http://ukmil.hopto.org/images/850/sw/5.jpg

you will then have the switch in half. here you can see how it looks

http://ukmil.hopto.org/images/850/sw/6.jpg

next, remove the small brass operating lever and the light cover as shown

http://ukmil.hopto.org/images/850/sw/7.jpg

next, get the rear section, in this case, the BLUE section, and remove the inside part from the switch, you will be left with this

http://ukmil.hopto.org/images/850/sw/8.jpg

here you can see the old bulb. and the wires which come from it
http://ukmil.hopto.org/images/850/sw/9.jpg

now, you have two choices here for removal. you can DESOLDER the ends, or do as I do here and SNIP the ends a small but away from the soldered joint
http://ukmil.hopto.org/images/850/sw/10.jpg

now its a simple task of pulling out the old bulb, place the new one in the holer, and resolder the new ends of the legs to the exisiting one

here is mine fitted

http://ukmil.hopto.org/images/850/sw/12.jpg

now we simply refit everything

first, place the holder back into the base section

http://ukmil.hopto.org/images/850/sw/13.jpg

then we place back the LIGHT COVER and the brass lever. The BRASS lever has 2 dimples in the centre section, these should sit on the two raised pieces on the switch. you will see them when you look

http://ukmil.hopto.org/images/850/sw/14.jpg

next is the bit which goes wrong, as it did is a couple of mine, you need to CARFULLY place the TOP SECTION back on

the problem comes here, is that it is a TIGHT FIT, and if you JOLT too much, the small brass lever will come off the raised pieces, and you switch will not work. SO carfully press the top back on and your switch is back together

http://ukmil.hopto.org/images/850/sw/15.jpg

now, on testing , if like i had, you switch no longer works, then the brass lever has almost certainly JUMPED off the pieces when you snapped closed the switch. you now have to reopen the switch and reset the lever, and close it again.

But now you should have a nice lit switch.

one you have done the first, each switch only takes 10 mins, and the bulb is only £1 from maplins