Dash Lights Dim, Boost Gauge gets brighter

SubiePrice88 · Post by **SubiePrice88** » Mon Mar 30, 2009 4:20 am

So I recentley installed a Autometer boost gauge. Spliced the power wire into the ash tray light and the ground... well to a ground. The only issue is that when I dim the dash lights the Boost gauge gets brighter, and when the dash lights are on the brightest setting the boost gauge doesnt illuminate. Whats causing this to happen?

asc_up · Post by **asc_up** » Mon Mar 30, 2009 5:57 am

Did you accidentally mix up the wires?

PhyrraM · Post by **PhyrraM** » Mon Mar 30, 2009 6:16 am

The dash lighs do not use a normal ground. They are grounded through the dimmer switch.

What is happening is that when you dim the dash lights your pulling that wire up closer to 12v. So the main dash lights are at 12v (battery) minus ~9v (dimmer) = ~3v (dim bulb). But your added gauge is at ~9v (dimmer) - 0V = ~9V (bright bulb).

When you turn the dash lights up your pushing that wires voltage down. Main lights 12v - ~3v (dimmer) = ~9v (bright bulb). Boost gauge is ~3v - 0v = ~3v (dim).

Basically, take the wire you have on the direct ground and move it to the switched illumination wire. It will be the wire that stays at 12v no matter where the dimmer is turned to. I'd tell you the colors, but I don't have my diagrams handy.

SubiePrice88 · Post by **SubiePrice88** » Mon Mar 30, 2009 9:49 pm

So just move the ground to the switched illum. wire. Where is the switched illumination wire located?

Post by **Legacy777** » Fri Apr 03, 2009 2:48 am

Tie into one of the illumination wiring points for any switch or light.

SubiePrice88 · Post by **SubiePrice88** » Fri Apr 03, 2009 3:18 am

Alright having a noob moment and need to clear this up.

Im looking at the wiring schamatic for the interior lights. It shows "Illumination Control Module" 6 wires come out of it 1 being a ground.

So do I leave the hot wire I have for the gauge spliced into the hot wire of the ash tray light and move the ground to the ground on the Illumination control?

Post by **Legacy777** » Fri Apr 03, 2009 6:47 pm

No,

You want to leave your switched 12v source tied in like you have it, and then tie into pin 2 (YL - Yellow Blue) for your ground. If you do this, the boost gauge light should dim with the other lights.

SubiePrice88 · Post by **SubiePrice88** » Fri Apr 03, 2009 8:21 pm

Alright got it, sorry about that. Ill give it a go and see what happens.

Thanks Guys

SubiePrice88 · Post by **SubiePrice88** » Fri Apr 03, 2009 11:33 pm

YAY!

The gauge dims with the lights now! Thanks for the help!

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Dash Lights Dim, Boost Gauge gets brighter

Dash Lights Dim, Boost Gauge gets brighter