Illumination wire ... CD Stereo Radio install - YotaTech Forums

General Electrical & Lighting Related Topics Ask here for electrical, wiring, and lighting info for your rig that could apply to all years

Illumination wire ... CD Stereo Radio install

LinkBack Thread Tools Search this Thread
Old 02-03-2006, 09:40 AM   #1
Registered User
Thread Starter
Join Date: Dec 2005
Posts: 14
Illumination wire ... CD Stereo Radio install

After searching through some posts and some web hunting, I'm still a little leery of hooking up the Illumination Wire (IW) for a new head unit. This is on a 3rd Gen Taco, but may apply elsewhere I suspect. I'm replacing an older Alpine (no IW) with a new Alpine 9845.

I think I have it narrowed down using this procedure found at the 'Talk Audio' forums here: (Complete article)

Using a Multimeter to Solve Headunit Wiring Hell

5) Probe each of the loom/connectors using the red multimeter probe until you find a reading of around 12V. This is your permanent live wire. Label it using the pen and tape.

6) Turn on the ignition (set it to the "Acc"/"Accessory" position.. there's no need to start the engine. Probe all of the pins/wires except the one already identified as permanent live. When you find one with around 12V, label this up as the "ignition switched live"

7) Turn on your headlights, and repeat the process from step 6, ignoring already identified wires/pins. When you find a 12V signal, label this as your "illumination" wire (basically it tells the headunit to dim the display when your headlights are on).

So here's the factory plugs, plus a plug that I think was added later in an install.
Name:  Tacoma96FactoryRadioWiring.jpg
Views: 709
Size:  63.1 KB

The upper two plugs are the factory wiring, and I’m thinking the lower single wire plug (white/green stripe….had to Photoshop the green stripe in the photo to show properly) is something someone added the previous install.
Many of the places on the net show the Toyota factory wiring using a solid green wire for illumination. See:

This is clearly not the case in my ’96 Taco. The 12V ‘lights on’ wire is definitely green/red stripe. The thing that has me puzzled is the extra single plug wire that goes to 1.77V only when the lights are turned on. The white/green stripe wire on the single wire plug comes out of the harness and is then finds it’s way to the small white factory plug in the ‘O’ position of that plug.
Name:  ToyotaRadioPlugs.jpg
Views: 1132
Size:  138.4 KB

The 'O' position shows 'DO NOT USE' in the above diagram, but....???

I’m thinking I should hook up the Illumination wire from the alpine to the 1.77V first….and see if that works. If that doesn't work, I may try the 12V green/redstrip wire that goes to the large blue factory plug at the 'J' position. (Also shown as 'DO NOT USE').

Mostly I’m just not up to blowing fuses with this thing at this time. I’ve seen some threads where people have run into problems with the IW, so thought I’d check to see if anyone successfully done the IW and where they connected it to.
Sorry so long winded…..

Last edited by PygmyCowboy; 02-03-2006 at 09:47 AM.
PygmyCowboy is offline   Reply With Quote
Old 02-05-2006, 05:17 PM   #2
Registered User
Thread Starter
Join Date: Dec 2005
Posts: 14
Turns out the 12 V 'lights-on' wire on the factory plug....the green/red stripe, is the one to use for connecting to the head unit's Illumination wire. At least that's what the color code was on my '96 Tacoma.

Still don't know what the single wire plug was for, the one that showed 1.7V when the lights turned on. Ah well.
PygmyCowboy is offline   Reply With Quote
Old 02-05-2006, 07:28 PM   #3
Contributing Member
Elton's Avatar
Join Date: Jul 2005
Location: Siletz,Oregon
Posts: 12,261
it could be for the clock or the memory

Last edited by Elton; 02-06-2006 at 09:59 AM.
Elton is offline   Reply With Quote
Old 02-06-2006, 04:10 PM   #4
Registered User
Thread Starter
Join Date: Dec 2005
Posts: 14
Ya know, I think you're right. It seems to be the only other thing that's normally on.... and dims.... when lights are turned on.

Still why the H..... would it be connected to the small white factory radio plug??? Will likely remain one of the TMLs....Taco Mysteries of Life.
PygmyCowboy is offline   Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
Icentropy's $400 4runner build icentropy 86-95 Trucks & 4Runners 17 03-02-2017 12:38 PM
factory A/C wiring MO transplant 86-95 Trucks & 4Runners 8 05-11-2016 03:01 PM
1988 pickup oil pressure gauge wiring HELP! 88yodabasket 86-95 Trucks & 4Runners 15 07-13-2015 01:32 PM
1985 22re a/c install help bryan34w 84-85 Trucks & 4Runners 0 07-06-2015 05:53 PM
1st gen runner trailer wire routing toyota32 86-95 Trucks & 4Runners 6 07-06-2015 05:42 PM

alpine, cable, function, head, hook, illuminant, illumination, illunimation, radio, red, stereo, unit, wire, wires, wiring

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT -8. The time now is 09:46 PM.

2017 InternetBrands, Inc.
  • Ask a Question
    Get answers from community experts
Question Title:
Your question will be posted in: