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Discussion Starter #1
Well, I decided to be patient (i.e. lazy) and spend some time observing (i.e. procrastinating on) the problem I've been having with my instrument lights. Sometimes I turn on the headlights and the instruments light right up; other times, it takes a few minutes. One thing is constant, though; if I leave them on, they're fine indefinitely, but if I shut them off even for a second, it always takes several minutes for them to come back on. However, I don't notice any flickering like I would expect to see if a wire were loose or cracked.

Does this sound more like a relay problem, or a switch problem, or a dimmer rheostat problem?
 

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Discussion Starter #3
It's worth noting that ALL of the little red lights in the cabin don't work when the instrument cluster doesn't light up, though the spotlights do work, so I doubt it's an instrument cluster problem or a wiring harness problem.
 

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Well, all of the lights you're having issues with run through the dimmer control on the dash, and it contains a basic electronic circuit, so that's where I'd start to look...
 

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Discussion Starter #5
They all run through the headlight switch and the load reduction relay, too. That's the problem; I don't want to go yanking stuff until I have some idea what's busted.
 

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How's your drivers side door lock? OK? sometimes locks?
Do you still get a warning chime when the lights are on and door
open for example? I'm trying to figure out if your're having any
door control module weirdness.
 

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Discussion Starter #7
Everything else works properly -- except for Outside Air Temp and Gas Mileage readouts, but they run on a different circuit.

Anyway, the issue has been resolved. It was my Euroswitch. I remembered that I had my old US headlight switch, and when I plugged it in, the cluster lit right up. (Yes, I checked to make sure it wasn't lighting up with the Euroswitch immediately beforehand.)

Ah well, gotta get a new Euroswitch I guess. I've heard there are various manufacturers who make them; which brand is the best one?
 

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Well, glad you found it! I figured it wasn't the load reduction relay, because it would've caused other stuff not to work at the same time....
Anyway, My old euroswitch was doing some similar stuff, and I was able to fix it by soldering a few connection points that were basically lugs with slots cut in them that a wire passed through. I guess the idea was that there would be enough tension in the slots, but mine failed over time. Some solder on each of those, and I was good to go.

There's a pic on the first post of the Euroswitch GB that shows what I'm talking about here:
http://www.passatworld.com/forums/showpost.php?p=751985&postcount=1

 

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Yeah, I was looking at my original switch and my euroswitch last night -- my original switch is made of black plastic, and my euroswitch is made of white plastic with black paint on it. The circuit board doesn't look the same as yours, either. I guess I got one of the cheap ones.

Where did you get yours from?

EDIT: And how did you get the knob off of your switch?
 

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Just out of curiosity, what gets enabled if you install a transistor in the R1 position, an LED in the D9 position, and a wire and connecting pin in the 58 position?
 

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IIRC, everything came out the back of the switch.

I think R1 is for a pot, and not a transistor. Perhaps there was a version of the switch with the dimming control built in?
 

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That might make sense. That outline sure looks like a transistor, though...

On a different note, why do people insist on calling variable resistors "pots"? A "pot" is a potentiometer, i.e. a variable capacitor, used for frequency tuning among other things.
 

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That might make sense. That outline sure looks like a transistor, though...

On a different note, why do people insist on calling variable resistors "pots"? A "pot" is a potentiometer, i.e. a variable capacitor, used for frequency tuning among other things.
Potentiometer is a 3-lead resistive device, where two leads are the ends of the resistor, and the third lead is a "wiper" which moves up and down the resistor. For example, if you connected the first two leads to 5V and GND, respectively, turning the pot control would vary the wiper lead potential to anything between 5V and GND. If the wiper is wired to one of the two end leads, you then has a two-terminal device which varies resistance with the position of the control. Actually, you don't even need to wire it that way, just use the wiper and one end lead.

Variable capacitors are usually called by that name, i.e. variable capacitors.


If you put a transistor in that board where the R1 is shown, it enables the flux capacitor.
 

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That might make sense. That outline sure looks like a transistor, though...

On a different note, why do people insist on calling variable resistors "pots"? A "pot" is a potentiometer, i.e. a variable capacitor, used for frequency tuning among other things.
Yeah, the outline does resemble a transistor, or perhaps a trim pot?

I've never heard of a potentiometer being a variable capacitor before???
From Wikipedia: The present popular usage of the term potentiometer (or 'pot' for short) describes an electrical device which has a user-adjustable resistance. Usually, this is a three-terminal resistor with a sliding contact in the center (the wiper). If all three terminals are used, it can act as a variable voltage divider. If only two terminals are used (one side and the wiper), it acts as a variable resistor. Its shortcoming is that of corrosion or wearing of the sliding contact, especially if it is kept in one position.
 

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It's worth noting that ALL of the little red lights in the cabin don't work when the instrument cluster doesn't light up, though the spotlights do work, so I doubt it's an instrument cluster problem or a wiring harness problem.
My spotlights are actually on all of the time. My switch was going bad and I had a similar problem. I replaced with a $45 euro switch as opposed to the $260 DRL switch and problem solved.:thumbup:
 
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