[0566dmax]

I got a pair of 2015 style tow mirrors off of eBay for my 2005 gmc. the brand is Yitamotor and I was wondering if I would be able to get the front turn signal to also be a running light. I do not want to buy the wiring harness from boost auto. Does anybody have a way to make them running lights but also keep the turn signal function?

 

[flyinhawaiian968]

Yep, pretty easy since they're LED lights on the mirrors. Connect the led's to each side of your mirrors so they are working correctly, then take a feed from your parking lights to each mirror. Connect the two +12vdc wires (parking and turn signal) together, then split the turn signal wire behind that connection (so its before the connection, closer to the vehicle and not closer to the mirror), install a 1n5400 diode or similar size/rating so that the silver line on the diode faces the mirror. Something like this:

Don't forget, you'll need to do the same thing on the left mirror, so at least 4 diodes will be needed.

EDIT: had to update diodes direction! When I duplicated it, it flipped it 180º! Image should now be correct with both diodes pointing the same way.

 

[0566dmax]

Yep, pretty easy since they're LED lights on the mirrors. Connect the led's to each side of your mirrors so they are working correctly, then take a feed from your parking lights to each mirror. Connect the two +12vdc wires (parking and turn signal) together, then split the turn signal wire behind that connection (so its before the connection, closer to the vehicle and not closer to the mirror), install a 1n5400 diode or similar size/rating so that the silver line on the diode faces the mirror. Something like this:
View attachment 1104486


Don't forget, you'll need to do the same thing on the left mirror, so at least 4 diodes will be needed.

EDIT: had to update diodes direction! When I duplicated it, it flipped it 180º! Image should now be correct with both diodes pointing the same way.

Would I need to take the mirror apart to do this or would I be able to but it down the line a little bit?

 

[flyinhawaiian968]

Dammit. That's not gonna work with parking lights on. Need a relay to also shut off the parking lights when flashing.

 

[flyinhawaiian968]

You can do it inside the door or anywhere you have the two wires from the led turn lights in the mirror. Gimme a bit, I need to re-draw the diagram for a relay too.

 

[0566dmax]

Dammit. That's not gonna work with parking lights on. Need a relay to also shut off the parking lights when flashing.

I’m pretty sure it should work because it would increase the amperage if they was going at the same time so it should just dim and brighten it without shutting off. I don’t need them to completely shut off when the turn signal is on, I just want it to indicate that the turn signal is on.

 

[flyinhawaiian968]

Okay, second revision:

Note, this will reverse the flash at the mirror, so it will be off when others are on, on when the others are not flashing. To reverse this and have them all flash the same, you'll need to double up on relays to reverse the voltage, as well as adding diodes in to supress feed back into the other parking lights.

Its cheaper to do it with relays/diodes, but definitely not easier than just buying Boost Auto's wiring kit. They're basically doing the wiring for you, then just telling you where to tap each wire. These are fun for me to do, cuz I like screwin' with wiring and oddball stuff like this, but its not for everyone!

 

[0566dmax]

Okay, second revision:


View attachment 1104487

Note, this will reverse the flash at the mirror, so it will be off when others are on, on when the others are not flashing. To reverse this and have them all flash the same, you'll need to double up on relays to reverse the voltage, as well as adding diodes in to supress feed back into the other parking lights.

Its cheaper to do it with relays/diodes, but definitely not easier than just buying Boost Auto's wiring kit. They're basically doing the wiring for you, then just telling you where to tap each wire. These are fun for me to do, cuz I like screwin' with wiring and oddball stuff like this, but its not for everyone!

Thanks

 

[flyinhawaiian968]

I’m pretty sure it should work because it would increase the amperage if they was going at the same time so it should just dim and brighten it without shutting off. I don’t need them to completely shut off when the turn signal is on, I just want it to indicate that the turn signal is on.

Yep, it would do that, but I'm not sure if you'll notice the flashing since its being fed with both 12 volts, but you could add a resistor to the parking light wire before the diode! That would give you a slightly weaker parking light in the mirror, but it would be full brightness when turn signals are on. What size resistor? Couldn't tell you since I don't know what the led's amperage usage is, I'd say throw a couple on there and see how much dimming you want. Remember, resistors exchange power for heat, so the more power you pull away from the led lights, the more heat they're going to generate. Make sure your resistors have somewhere to mount where they won't melt/burn anything.

 

[JXsedan]

I did this on my 04 a few years ago. You will have to take the mirrors apart and wire only the front facing light. Otherwise the arrow in the glass will be on all the time. There is a few YouTube videos that explain it and what diodes & resistors to use. I cut the power wire to the front light, soldered on the 2 diodes like a ‘Y’, reconnect 1 of them to the wire you cut, connect the second to a new wire and fish that wire through the loom in the mirror arm and out into the door. Run a wire from each door to the distribution box by the left kick panel. If you want it to dim the new lights install the resistors here. Then connect to the marker signal in the box, I forget which terminal it is. And don’t forget to run the wires for the reverse/courtesy lights at the same time. Good Luck!