How-to Replace the A/C Controls Backlight Bulb

[manoverboard987]

How-to Replace the A/C Controls Backlight Bulb

words and pics by manoverboard987

WARNING: Read thru the entire How-to before proceeding. This procedure is very easy to screw up but also very easy when done correctly. As always, this is just a guide and you do this procedure at your own risk and you might hafta make small adjustments given your particular situation, etc.

It's a common problem in MkIVs of all kinds, but it's not that hard to correct.

NOTE: The pictures in this how-to are of the dials in my Jetta, but the procedure and parts are exactly the same in NBs.

You will need:
- 1 Replacement Mini Wedge Bulb (VW Part No N0177512)
- a tissue
- a piece of really small hose (~4mm ID), such as VW vacuum line (my dealer had scraps laying around, yours might too - see first attached pic to see what I mean)
- if no hose, a pair of very small needle-nosed pliers with the tips wrapped in electrical tape will suffice


The key word in this procedure is delicacy. The bulb is smaller than any other bulb you've ever seen, and is very VERY fragile. Any time I say to push the bulb in or pull it out, do so with the smallest amount of force you can and very slowly apply more. It won't take much force to accomplish your goal. Too much force leads to a broken bulb which means bits of glass down inside your center console and a broken bulb end which you hafta pull out of the socket. If you're using pliers, be 10 times as careful.

PROCEDURE
1. With vehicle power off and the key out of the ignition, turn the center A/C control knob (the fan speed knob) to position 2 (so that the knob is perfectly vertical).

2. Yank straight out on the center knob. Slowly apply force until it pops out. Behind the knob is attached a tube which surrounds the bulb, so BE CAREFUL!

3. Visually locate the bulb. If it's still in it's slot (which it most likely will be), you may proceed. If it's not, and you knew for sure there was one in there at some point, stop and locate it. (This involves taking apart your center console, which you can figure out how to do from other How-to's here on the org. If you still don't find it, it might have fallen out somewhere else or there may never have been one.)

4. Insert the hose into the hole, feeling when you come into contact with the bulb. Gently apply forward pressure so that the bulb gets pushed into the end of the hose. Once it's in, pull out on the hose so that the bulb pops out of its socket. (If using pliers, watch inside as you insert them and gently grab the bulb, and then pull out.)

5. Using the tissue to handle the new bulb, gently insert the round end into one end of the hose. (If you're using pliers, skip this step.)

6. Using a reverse version of step #4, insert the new bulb into its socket. Gently apply force up until it pops into its socket. You might find that once it's in, a gentle twisting motion may be needed to dislodge the bulb from the hose. (Plier folks, it's better to gently push in with your pinky or something equally soft than your pliers.)

7. Turn the car on to the Accessory ignition position, and turn your lights on. (Your fan will turn on when you turn the key, so don't freak out.) If you see the bulb illuminate, turn the lights off and move on. If it doesn't illuminate, turn the car back off and try to push the bulb fully into its socket - remember, you need to feel a pop. If if it still doesnt illuminate, take the bulb out and make sure it didn't blow, then make sure it pops back in. If it still doesn't work, odds are that the socket has gone bad, and that's a whole 'nother ballgame.

8. Once you've made sure that it works and turned the car back off, gently replace the knob and turn it back to "0". You're done!

[SilverSportNOLA]

Good Writeup .... I should have thought of the vac hose when I changed the bulb in my OEM Radio on my Ford Truck .... NAPA had a bulb similar to that. It was a #73 for 99 cents for my truck radio, might be the same ... about 3/4 inch from tip to bottom of the wedge and about 5mm diameter.

[callisto9]

dumb question, but is that bulb just for that dial, or does it light up all three dials?

thanks for the awesome write-up!

[iScott]

Very nice, Kris. I need to do this in my mom's Jetta so this works out great!

[iScott]

Originally Posted by callisto9

dumb question, but is that bulb just for that dial, or does it light up all three dials?

x2

[manoverboard987]

Originally Posted by callisto9

dumb question, but is that bulb just for that dial, or does it light up all three dials?

thanks for the awesome write-up!

It lights up all 3. There's a red plastic light diffuser around the bulb and that lights up the other 2.

Originally Posted by SilverSportNOLA

Good Writeup .... I should have thought of the vac hose when I changed the bulb in my OEM Radio on my Ford Truck .... NAPA had a bulb similar to that. It was a #73 for 99 cents for my truck radio, might be the same ... about 3/4 inch from tip to bottom of the wedge and about 5mm diameter.

That bulb sounds bigger around than ours. Ours fits just right in that piece of 3.5mm ID vac line.