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33 Posts
that would be sweet but annoying if the dome light turned on everytime you put your turnsignal on

· Registered
33 Posts
yeah that would be terrible

· Registered
93 Posts
Ok I am first going to start this off by saying I have not done this, but it is a very simple thing to do, all of my instructions are going to be based of wiring on one of my tech sites I use from work (I am a car stereo/alarm installer). So do this at YOUR OWN RISK. If you screw anything up I am not liable, and by reading this you understand that. All parts are estimated as I have not done this personally (I may do it just for a walk through if I get bored one day). If anyone does it and would like to add pictures just let me know and we can make it a new thread or something

If you have a DEI alarm (or other brands, I use viper at my shop) you can simply wire this into your alarm or have your installer do it for you.

Before beginning there are only 2 things that I am unsure of on this since I havent done it myself
1 - when driving (or if the car is on) if the domelight is turned on it may activate the relay causing either backfeeding of power or your turn signals to not work from the switch, this could be fixed by adding a second relay that is wired to ignition that only allows power to the relay described below when the car is off
2 - If wired to the turn signal wires these lights may flash when active (I havent tested so I wouldnt know) to get the lights to not flash you may have to run wires to either the door harness or into the door itself @ the mirror.
That being said someone can try this and let us know what happens, what worked, what didnt and any work arounds. Im simply trying to help those who want to do this.

Please read all the way through and if you dont feel like your up to it, its probably best you dont.

Parts needed:
16-18 gauge wire around 6ft should be good (multiple colors would probably be best so you know what is going where) I recommend red, black & blue or yellow
1 SPDT (single pole double throw) relay
Soldering supplies (or whatever equipment you feel comfortable with but I recommend soldering)
1 amp Diodes (get a few extra in case any get messed up)

Step 1 - remove the knee bolster panel

Step 2 - locate necessary wires
12 Volts white (30A) + ignition switch, white 8 pin plug, pin 7
- you will want to use this wire to supply your relay with its power for activation and to supply power for your lights, use a inline fuse when hooking up to this wire

Dome Supervision white - dash fuse box, white 6 pin plug (K), pin 2
-this will be your neg trigger wire for your relay (this will turn it on)

Turn Signal (Left) yellow + dash fuse box, white 30 pin plug (A), pin 27
Turn Signal (Right) lt. blue + dash fuse box, white 30 pin plug (A), pin 28
-these wires will need to be powered on by the relay when the domelight is active

Step 3
After locating all your wires and testing them, figure out where your going to place your relay and cut your wires to the necessary length (do not hook them up to the car at this time it will be easier to wire the relay outside of the car then hook it up)

Red wire - 12v (from the white 30a wire @ the ign harness) through a fuse to terminals 86 & also 30 on your relay, this will provide power for the relay and the turn signals when activated
Black wire - Dome supervision (white - @ fuse panel) to terminal 85, this will supply the negative trigger to power on your relay
87a will not be used for this, by not using this terminal it will allow your turn signals to operate normally when your driving
Yellow or Blue wire - (turn signals left and right, yellow and lt blue +)This will be attached to terminal 87, from this terminal you will want to run your diodes to prevent backfeeding to the oppposite turn signal when used while driving

You will want to run the anode side (the side without the stripe) on the relay side since we are using a positive signal, the stripe side will be the car side of the relay (refrence the 12volt link if your unsure) I highly recommend soldering these on the wire
You will then split the signal to each turn signal from the diodes to turn signal wires.
After hooking everything up on the relay you can go into your car and wire everything into place

This link will help you understand how a relay works if you don't already
This will help you understand diodes

After connecting all your wires (hopefully before soldering everything in place) test the functionality and make sure its what you want.

Keep in mind I have not tested this, this is all using my head and diagrams and wiring guides. Test all wires with a Meter before hooking up wires and please test and test again to make sure there are no problems.
Images used from

Hope ive helped someone out there, if you want to edit this or copy and paste it into the first post, feel free to add or remove things as needed.

Good luck!

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