Scion radio illumination

[alia176]

what are y'all doing in order for:

1) backlit keys to light up
2) dash light dimming function to work

The orange/white Illumination wire out of the PAC TATO unit is connected to the orange Illumination wire coming out of the Scion T1819 HU. However, when the headlights come on, the display goes dark.

Thanks for your help.

 

[S4TA]

I had the exact same issue and messed some things up before reading the post below. If you follow the advice below, you should be fine.

After finding the post below, I did everything the post below said to do and I still had the issue. The next night, I noticed that my gauge lights no longer worked when I turned on my headlights. All other interior lights worked and even dimmed. I went to a local savage yard, pulled a dimmer for $5, wired the HU per the post below, and all was good.

When I was trying to figure out my HU back-lighting, before reading the post below, I must of blown my dimmer. I then proceeded to waste 2 days trying to figure out why my wiring was bad when it was the dimmer the whole time.

I ran into the same problem when I did the install over the summer, you need to connect pins 2 (ILL+) and 12(ILL-) from the R12 connector (20 pin harness on the vehicle side) to their corresponding pins on the 10P+6P (ILL+ and ILL-) on the head unit side. See the pics below for reference.

Also, you can use a multi-meter to verify by probing pins 2 and 12 on the vehicle harness. With the headlights on you it should read +12-13v and with the headlights off it should read 0v.

Hope this helps.

Here is the link:http://www.toyota-4runner.org/2211186-post4.html

 

[alia176]

ok, thanks for the info. Even though I don't have the FR-S Scion radio, the theory is the same. I need to connect the Illum + and - from the head unit to the Illum + and - to the vehicle.

I'll get going on this when I get home tonight.

On another note, I have two brown color wires from the radio and one of them says MUTE on them. Are these going anywhere?

EDIT:
- one of the MUTE wire that's brown but NOT labeled as MUTE is the ILLUM (-) on the 6P connector. Mystery solved!!!!
- The illumination works properly. The keys are backlit when the headlights are turned on and the dimmer switch controls the brightness of everything.

Thanks again.