connecting gauge to dimmer switch Gen4

[andyjs2]

So, I've been racking my brain, staring at wiring diagrams and testing every possible combination in the back of the dimmer switch...

I just bought a boost gauge and I'm wanting it to operate as the dash lights do, (auto dims with headlights etc)

So far all I know is

Purple = on with headlights
Green =
Blue/black =
Blue =
Grey =
Black/white = negative for dash lights
I cant even get my head around what the blues and grey do, but the blues are like negatives I assumed as they light up the led with the purple

someone please help

[andy_mac]

I just tapped mine into my stereo wiring since it was the easiest for finding the right coloured wires to use, everything reached fine for me. Seems clearer than wherever you're digging around. What brand gauge did you get? Pretty sure i only needed ground, cont power, accessory and illum for a defi setup

When using stereo colours it will be
Cont power - blue/red
Accessory - yellow/red
Ground - black
Illum - black/white

http://ae64.com/Legacy-pinout.htm

[bigBADbenny]

Libs use variable resistance for cabin dimming, meaning Andy's approach is the easiest solution

[andyjs2]

It's an autometer mechanical gauge
So it has a positive and negative for lighting and that's it

That method would be for lights off when headlights off and lights on with headlights on
I'm looking for lights always on, but dim with headlights on, like the oem dash lights

[andyjs2]

Okay so I just reread this
And we're both andy but I'm assuming bbb meant you haha, so technically if I use black as ground and black white as illumination I should be sweet?

will check it out in the morning


Update: silly me, obviously black/white is the illumination - with violet being the +
Though neither of these combined with anything has the desired effect, any old acc power will be good for the same brightnesa all the time, but the gauge doesn't dim when you turn the headlights on, only dims to the dimmer dial/switch whatever
Which is what I'm trying to work out how to do

[bigBADbenny]

Since the gauge has basic illumination, maybe the variable resistance dash illumination would work?
Have to research that one before blowing something up
https://www.google.com.au/search?q=dimm ... ent=safari

The answer is yes if your gauge is actually dimmable, eg incandescent, if you use a circuit to flip the signal: from nasioc...


What about making my gauges dimmable? The links of interest below has some tips. It is also worth mentioning that the Subaru dimming circuit is non-standard since it is fixed positive/variable negative. Most electrical gauges are wired for the opposite, fixed negative/variable positive. This can cause problems if they are connected to the car's dimming circuit. Such gauges that share a ground for measurement and lighting must NOT be connected to the variable illumination wiring. To install such gauges so that they dim, an additional circuit is needed to "flip" the polarity of the illumination to the gauge.

The circuit is detailed here:
http://www.scoobymods.com/showthread.ph ... tml?t=3115
I'm a member so I logged in and checked that the pics are still up
You should check if your gauge illumination is actually dimmable first


.

[andyjs2]

The gauge is led lit, the same as the lights in the dash

I can get the gauge to dim with the dash lights, but not in the way I want it to (you have a gen4 lib, so you know what I'm saying, the dimmer has the extra notch that is always bright, then one click down is bright with headlights off and dim with them on, and that's what I want the gauge to do)

I can just hook it up to an acc with the illumination -
But then the gauge will be full brightness regardless of night mode etc, but any setting under that it will dim with the dash lights (ie rolling the dimmer down will in turn dim the gauge, but it will be from full brightness, not matching the night mode in the dash)

I'm trying to be as clear as possible but my head is swimming haha

[kiwigene]

Where are you mounting the gauge?

I put mine in the cubby and just spliced off the connector that goes to the clock.
That should get you what you are looking for. Dimmer control and auto-dimming when the headlights are on.

Although, that being said, even on the dimmest setting my gauge is a little brighter than the rest of the dash.
Probably because the led bulb is rated differently. Considering it's only in my peripheral vision it's ok it's a bit brighter.
It's there to inform/alert me anyway. I can always close the cubby if it bothers me.

You could always apply some tint film to the gauge. Or open the gauge and see if the bulb can be tinted/painted.

[andyjs2]

I'm mounting it on he steering column, and Un?fortunately I have the gps so I wish it was that simple haha
Do you remember the colour of the wires?
Surely the harness would be in the foe the clock in my car anyway, they'd just either plug that in or the gps you'd think

Might have to find the actual feed behind the dash lights

[andyjs2]

I've progressed to the opposite of what I want, but getting there haha
Using the dimmer negative and an accessory, it dims with headlights off and bright with headlights on, I wish leds were as easy to swap polarity as incandescent

[bigBADbenny]

Did you read the links?
That's all the info required afaik.
As for dimming a too bright gauge: one of the links describes using a resistor as an alternative to tint or painting the bulb

[andyjs2]

I did read the links, but the way I'm seeing it is that's for an electronic gauge that would be disrupted by the variable negative, correct?
My gauge is mechanical so that shouldn't be an issue

I just read that orange is illumination (-)
I thought it was black/white

So I'm.about to go try that out
See what I get

[bigBADbenny]

Great.
Everything I've read on the subject points to needing to make the inversion circuit as described in the subymods thread.

An alternative might be a DIY auto dimmer a la vent boost gauge et al...

https://www.google.com.au/search?q=auto ... ent=safari
Autometer even make one

[andyjs2]

If the orange does nothing, I'll have a crack at the inversion circuit
Thanks for your time man, appreciate all your help!

[bigBADbenny]

I spent a little time researching making an ambient light sensor circuit, using a photosensor, photodiode or LDR (Light Dependent Resistor).
http://www.instructables.com/id/Simple- ... /?ALLSTEPS
Something like that could work independently of the cars dimming, but I'd need to nut out how to invert the dimming as that instructable circuit brightens in the dark, the opposite of what we want.
Any electronics experts out there?