Illumination wire options

Roadrunner · Postby **Roadrunner** » Sun Apr 20, 2014 8:41 pm

I have replaced the headunit in my SE and wired the illumination wire to the factory spot.
I have since installed a boost gauge that requires wiring into 12v/earth/illumination so I tapped into the headunits IGN and illumination wires, but now have a very low volume hum through the speakers with the headlights on.
I want to separate the gauge illumination wires from the HU wires, but where else can I tap into IGN and Lights? This would need to be illumination not connected to the dimmer (the instructions say not to)

Magpie · Postby **Magpie** » Mon Apr 21, 2014 8:46 am

Most gauge installation instructions advise against using the same ground as the stereo as well as ones that share power with the vehicle’s stereo, ignition system, and fuel pump

sailaholic · Postby **sailaholic** » Mon Apr 21, 2014 9:06 am

Tap the park lights

Sent from my iPhone using Tapatalk

Roadrunner · Postby **Roadrunner** » Mon Apr 21, 2014 2:42 pm

Magpie wrote:Most gauge installation instructions advise against using the same ground as the stereo as well as ones that share power with the vehicle’s stereo, ignition system, and fuel pump

Yeah they are separate earths but the stereo was out at the time and access was easy so temporarily tapped into acc and illum there.
Having a look around I'm not sure what wires are what under the dash and what wires are for illumination but not connected to the dimmer.
Alternatively I guess I could just connect the illumination wire to the acc wire and have the lights on all the time, but I'd rather not.

Roadrunner · Postby **Roadrunner** » Mon Apr 21, 2014 2:43 pm

sailaholic wrote:Tap the park lights

Sent from my iPhone using Tapatalk

Do you know which wires these are? Ie where and what colour under the dash

taminga16 · Postby **taminga16** » Mon Apr 21, 2014 3:04 pm

Trace the required cable from the fuse block.
Greg.

and1 · Postby **and1** » Tue Apr 22, 2014 12:31 am

I tapped the dimmer switch for illumination. Use a multimeter and find the 2 wires of the 3. One will be the ground, one the illumination 12V and the other a variable resistance corresponding to the dial position of the dimmer. Use the 12V and ground.

Postby **Okibi** » Tue Apr 22, 2014 2:55 am

One of these makes it easy ... and reversible

http://www.ebay.com.au/itm/Small-ACS-J-Add-A-Circuit-Piggy-Back-Pluggable-Standard-Blade-Tap-Fuse-Hold-PSHG-/380846620553?pt=AU_B_I_Electrical_Test_Equipment&hash=item58ac3a3f89&_uhb=1

Roadrunner · Postby **Roadrunner** » Tue Apr 22, 2014 1:40 pm

Okibi wrote:One of these makes it easy ... and reversible

http://www.ebay.com.au/itm/Small-ACS-J-Add-A-Circuit-Piggy-Back-Pluggable-Standard-Blade-Tap-Fuse-Hold-PSHG-/380846620553?pt=AU_B_I_Electrical_Test_Equipment&hash=item58ac3a3f89&_uhb=1

That looks great! So just plug it into where a 15amp fuse is in the fuseblock and away you go?

I might however look at tapping the dimmer switch as and1 suggests, but would this mean the gauge lights will be on as soon as the gauge gets 12v power regardless of if the car lights are on or not?

Edit: Dont worry having a moment :oops:

I know what to do and where to connect too

Nevyn72 · Postby **Nevyn72** » Tue Apr 22, 2014 3:15 pm

Roadrunner wrote:
Okibi wrote:One of these makes it easy ... and reversible

http://www.ebay.com.au/itm/Small-ACS-J-Add-A-Circuit-Piggy-Back-Pluggable-Standard-Blade-Tap-Fuse-Hold-PSHG-/380846620553?pt=AU_B_I_Electrical_Test_Equipment&hash=item58ac3a3f89&_uhb=1

That looks great! So just plug it into where a 15amp fuse is in the fuseblock and away you go?

Agreed, that's why I just ordered 2 of them this morning! :mrgreen:

I probably won't use them long term, but they will be great to test circuits to make sure the one I want to tap is the right one! :wink:

Roadrunner · Postby **Roadrunner** » Tue Apr 22, 2014 5:54 pm

Ohh Jaycar have them for $4.95 each and I can get them now instead of two weeks time. Might pick some up this afternoon for the upcoming weekend.
I'm at work and cant remember, does the MX5 use standard fuses or the mini ones??

Nevyn72 · Postby **Nevyn72** » Tue Apr 22, 2014 5:57 pm

Roadrunner wrote:Ohh Jaycar have them for $4.95 each and I can get them now instead of two weeks time. Might pick some up this afternoon for the upcoming weekend.
I'm at work and cant remember, does the MX5 use standard fuses or the mini ones??

Standard in the engine bay fusebox, mini in the dash fusebox. :wink:

Happy to buy from the 'Bay as I don't need them in a hurry, doing some engine bay mods first......

Roadrunner · Postby **Roadrunner** » Tue Apr 22, 2014 6:58 pm

Eh what's a few dollars for convenience

I drive past a jaycar on the way home from work

Roadrunner · Postby **Roadrunner** » Fri Apr 25, 2014 7:42 pm

Reporting back that those jumper leads work a treat.
Tapped into the cig lighter fuse (gauge wire on a 10a fuse) tapped the dimmers illumination wire and ran new ground.
All perfect, no more hums or buzzing through the stereo and I got to use my soldering iron again

KevGoat · Postby **KevGoat** » Fri Apr 25, 2014 10:37 pm

Very cool. In all the car wiring I've done, I'd not come across those jumpers! So simple! Be remembering those for future projects ...

Sent from my GT-I9100T using Tapatalk