Dome Trigger for LED and Relay, 2000 Toyota Celica GTS

2000 Toyota Celica gts
Dome is negative trigger ground

I am trying to install 4 or more led strip in the car. Read the topic on this site and Google but still a little confuse. My dome dims when it turns off I would like to keep that function.

Here is my plan use fusebox with relay and the dome switch as trigger.

+12v inline fuse 100amp to 100amp fuse box. Wire is 4 awg because fuse box will be in trunk.

Relay 12v 30/40amp 5pin
Pin 86 and 30 connect to each other to fuse box with fuse +12v

Pin 87 well be acc to the led
Pin 87a leave alone
Pin 85 connecting to dome trigger (-)

Now for diode pin 86 |<-- 85 on the coil or can I tap it into the wire 2 to 3 inch away from the relay.

Well this work with out buzzing and keeping dim function?

Or

Dome use 7.5a

Change dome light to led use .012a and the led is .08a per strip 4x.08a =.32a
Get 2 wires connect to dome light (-) and (+) and connect to led. Diode (+) side facing dome trigger. Still have amp to spare.

I would like to use the first option because I bought all the item already lol.

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Toyota

Oh should I also put a diode from relay (-) 85 |<-- to dome (-) wire? Its a negative trigger.

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Toyota

If your LED strips total draw is 0.32A then just feed the strips directly from the ACC and dome light positive feed using 2 1A diodes (1N4001, etc) to isolate the feeds. Forget the fuse and relay.

Ty for the replay but I wanted to add a fuse box because later on I'm going to add more gadget. Diode is the problem I'm having pin 86 well be connected to 30 so 86/30 -->| 30 ? Or other way around. The 30 is the dome negative trigger. Do I also put a diode from 30 to dome negative triggers wire.

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Toyota

terk] wrote:

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Ty for the replay but I wanted to add a fuse box because later on I'm going to add more gadget. Diode is the problem I'm having pin 86 well be connected to 30 so 86/30 -->| 30 ? Or other way around. The 30 is the dome negative trigger. Do I also put a diode from 30 to dome negative triggers wire.

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Are you sure your dome light is PWM'ed on the ground side? Usually the dome lights that have the dimming/fade feature are modulated on the plus side. Did you make any measurements with a DMM?

4 wires to dome.

Red always live

Off dome pin:
Black is ground from trigger to bulb

Live wire middle and bot when lights on

Live wire door position bot right black/white. But door open all 3 live.

Live wire bottom right black/white when lights off

I use a multi meter says my car is negitve trigger. It also has dim i check when closing the door





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Toyota

Convert your negative trigger to a positive output using a relay per

https://www.the12volt.com/relays/relaydiagram8.html

Feed the relay output to your LEDs through a diode.
Feed ACC to your LEDs through a 2nd diode.

Use a small relay - 10A contact rating is more than adequate. Huge 40A relay is not required

I think I got it I place diode (-) end facing 86 and other end (+) to 85. Tested it, sparks when no diode. I place one it took away the spark when releasing the wire from 85. So my first post at top is good. Thanks 4 the relay :)

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Toyota