Flakey Dash Light Brightness Knob Fix : Tutorial

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Flakey Dash Light Brightness Knob Fix : Tutorial
Topic Started: Tue Nov 27, 2007 8:03 pm (938 Views)
kentronix	Tue Nov 27, 2007 8:03 pm Post #1
Admin Posts: 16,349 Group: Admin Member #147 Joined: January 20, 2006	May not be worth doing on its own but if your clusters coming out you may as well. It will fix the issues where rotating the dash light illumination knob will result in drop outs where the lights drop off every now and then. Remove the cluster from the car as described in the dash removal tutorial (or many other posts). The rear of mine looks like this but there is some variation. However all will only require removal of one screw to remove the potentiometer unit. After removal your potentiometer will look like this, well, perhaps without the strange fluff :- You can see how the metal cover is clamped over the base. If your not confident then simply spray lots of wd40 (or AF spray) under the metal cover and clean with a match stick or something similar. Concertrate on the curved springy part and also the pinhead looking blob at the end. If your more confident then open the unit up and clean all the parts more thuroughlly. The two springs shown in the pic will most likely pop out when you open it up so be ready for them. They actually go in between the plastic wiper part and the metal wiper part, pushing the metal bit onto the curved spring. Refitting is pretty simple really, it may take a couple of goes to keep the springs in place while you refit the cover, and when you attach the whole unit back to the back of the cluster you should rotate the brightness knob on the front of the cluster so it will align and drop back in. This tutorial has been brought to you by the letter K and the letter E and the letter N and the letter T and the letter R ..........



Lewis 190E 2.5 16	Tue Nov 27, 2007 8:04 pm Post #2
I love speedbumps Posts: 6,597 Group: Members Member #918 Joined: February 7, 2007	Nice one, done mine last year and its been fine since... Anyway nice guide...



kentronix	Tue Nov 27, 2007 8:20 pm Post #3
Admin Posts: 16,349 Group: Admin Member #147 Joined: January 20, 2006	cheers matey, nice to be appreciated. Its not particularly hard to do but its nice for people too see what to expect before they start the job.



Rich27	Wed Nov 28, 2007 8:45 am Post #4
If it has tits or an engine it will be trouble Posts: 13,264 Group: Members Member #348 Joined: June 15, 2006	Kenny, How the heck did you manage to get it Fluffy like that?



kentronix	Wed Nov 28, 2007 8:49 am Post #5
Admin Posts: 16,349 Group: Admin Member #147 Joined: January 20, 2006	Rich27 Nov 28 2007, 09:45 AM Kenny, How the heck did you manage to get it Fluffy like that? I have no idea, its stuck on good and proper too, I guess its the behind dash version of pocket fluff.



NEIL	Wed Nov 28, 2007 8:52 am Post #6
Fewer Posts than Kenny Posts: 16,160 Group: Members Member #63 Joined: November 18, 2005	Nice work! Tell me; Does Potentiometer = Rheostat?



kentronix	Thu Nov 29, 2007 10:52 pm Post #7
Admin Posts: 16,349 Group: Admin Member #147 Joined: January 20, 2006	The sort answer is yes. Of course that wont do me so...... A potentiometer (or pot) is short for potential devider. What most people call a voltage is really a potential difference. A potential devider will put a resistance across the potential difference (from +ve to -ve) and allow the output (middle pin) to vary anywhere from one end to the other. Thus allowing the result to vary between the minimum and maximum 'voltage'. Be it light output, volume, etc. In fact the pics above make it really clear how this particular one works. The spring has a resistance. One end will be close to zero and one is close to 12v. You sweep between the two. Rheostat is normally used for higher voltage stuff like mains boilers and stuff but they are the same item. Lecture over if could you return the textbooks to the front as you leave.



julian	Fri Nov 30, 2007 6:21 pm Post #8
Member Posts: 2,584 Group: Members Member #831 Joined: January 16, 2007	Great stuff, photos are great too, hate trying to do stuff from instructions only. Can't read :lol:



MICHAEL	Fri Nov 30, 2007 8:44 pm Post #9
Member Posts: 5,632 Group: Members Member #555 Joined: September 28, 2006	190Evoluzione Nov 28 2007, 09:52 AM Nice work! Tell me; Does Potentiometer = Rheostat? I, in my ignorance, always thought a potentiometer worked by Mercury. :lol: Wherever did I get that idea. :lol:



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