How-To Install LED Side Mirror Turn Signals

:
2021 RDX A-Spec
No thanks to the selfish members who have done this already and failed to provide comprehensive details despite the high level of interest, I installed LED mirror turn signals this weekend. Here's how I did it...

Time: 2 hours
Difficulty: Moderate
Supplies:
Flathead screwdriver
Torx scredriver
Wrench
16-18 gauge wire (approx 40-50 ft)
Coat hanger (or your favorite wire snaking tool)
Electric tape
T-tap connectors (4)
Splicing connectors (4)

Step 1: Disassemble the Mirror

a) Begin by popping off the mirror from it's gimbal. To do this push the mirror "down and away" from the car and pull from the top corner closest to the car. The plastic ball-and-socket should then dislocate. There are two fat plastic rods also connected to the mirror which control it's position - do NOT pull them off. With the mirror off its gimbal you'll be able to see the clips for the front cover behind it.

b) Remove mirror cover. Using a screwdriver push the clips for the front cover through their holes and pull on the cover from the frontside. Frankly, this is where you can just go all-out and yank that cover off since you'll be throwing it away anyhow, so broken clips are no sweat. With the cover removed you'll quickly realize that snaking the wires through the door is going to take some more work.

c) Take mirror off it's hinge. Do this by removing the three screws under the mirror assembly. (Requires torx screwdriver, boo.) With the mirror off it's hinge you'll see the path your wires will need to make.

d) Remove inside door trim near mirror. This mostly rectangle piece of plastic simply pops off with some force. Don't worry, there is just one clip and it is pretty durable, so just yank.

e) Unbolt the mirror from the door. After you remove the trim per the previous step you'll notice three bolts. Unbolt them and pull the plastic trim from the outside.

With these steps complete you'll see how you need to route the wires into the door.

Step 2: Route Wire to Car Body

This step is straightforward. With the mirror disassembled run 16-18 gauge wire from the mirror the door and down to the rubber conduit where all other wires lead to the car body. You can easily tuck the wire behind the door trim between the mirror and the conduit. Note: You'll need to route two sets of wires from the mirrors to the car body (the green wire coming out of the LED mirror has been incorrectly referred to as the ground wire, but you definitely need to connect it).

Step 3: Route Wire to Headlights

Now you have a choice. Ideally you should route the wires into the cabin, through the firewall, and into the engine bay. I tried this but decided it was way too much grief to snake the wires through the firewall with all the other wiring. So I took an easier route...

At this point your wires should be routed through the rubber conduit between the door and the body of the car. If you look closely at the door jam you'll notice that you can simply snake the wires just behind the front quarter panel all the way to the engine bay. You can quickly do this using a coat hanger or something similar. Conveniently your wires will emerge within a foot of the headlight.

Step 4: Tap Wires into the Turn Signal

We know which wires we need to tap into thanks to Int3grity. The easiest way to identify them is to look for the bright white wrapped wires (I think there are 5 or 6 wires bundled). You can tap into the red and black ones at any point using the t-tap connectors. Connect the male connectors (they should come with the t-tap connectors) to the wires you ran into the engine compartment, and then plug them into to the t-taps.

Step 5: Attach LED turn signal

Using your favorite splicing hardware, attach the green and white wires from the LED to the wires you ran into the car. Before splicing you'll want to test your turn signal on to determine the correct wire pairing.

Step 6: Tape-off Wires and Reassemble Everything

You'll need to tape the loose wires along their path from the door to the engine compartment for good measure. Then reassemble everything. The final step should be snapping the LED and mirror cover into place.
 
There is only one member on here who has done the factory LED mirror install I thought? At any rate, great writeup. I wish I had access to this when I did my custom LED install. Just a few suggestions. You don't have to run the ground wire all the way from the mirrors to the front of the car. You can tap the ground wire at the ground wire for the electric mirrors. Also... routing through the factory grommet is fairly easy and I would HIGHLY recommend it. Other than that, follow JMHUMR's instructions and you're set.
 
Thanks for the write up! Some pics during each of the stages would have been a little more helpful, though.
 
There is only one member on here who has done the factory LED mirror install I thought? At any rate, great writeup. I wish I had access to this when I did my custom LED install. Just a few suggestions. You don't have to run the ground wire all the way from the mirrors to the front of the car. You can tap the ground wire at the ground wire for the electric mirrors. Also... routing through the factory grommet is fairly easy and I would HIGHLY recommend it. Other than that, follow JMHUMR's instructions and you're set.

About the ground wire: I tried simply grounding the wire, but for some reason it didn't work. I wouldn't be surprised if perhaps my grounding location was no good -- by the time I got to that point I was so darn frustrated with the project that I was happy just to see them work.

What factory grommet are you talking about? If you're talking about the rubber conduit that routes about a 1" thick bundle of wires through the firewall just behind the brake pedal then I'd certainly like to know how that is easy. I poked around there for a while and couldn't find any reasonable path.

I got the impression there were at least a couple people who have done it. One guy posted pictures and was particularly brief and immature when people were asking how he did it. It was as if he just wanted to brag and not help anyone. Anyhow, my comment was inspired by him after what was a VERY frustrating install thanks to having no instructions. Man am I glad I'm done with the install, haha. :)
 
^Ya I think a shop did all the work for him... but you're right, I remember that thread. He could have just come out and say he had no idea.

For the big factory grommet... you take a long flathead screwdriver with your wire over the tip of it... and PUSH. Bam... it'll come out the other side with your screwdriver tip. That's one way... the other is to make the hole with the screwdriver and then use a wire pulller/grabber. I do audio installs so I had access to the puller and used it in conjunction with the screwdriver.
 
Good instructions all around.. Ill post photos of my install and show you all why running wiring to the engine cabin does not make any sense... Its much quicker/easier/more professional to run wiring to the harness thats right beside the passanger side door, and yes... its so much better looking to run your wiring through the factory door harness, skipping this step leads to frayed wires down the road, and in the case of my old dodge neon door locks, spotty actuators....


Heres a hint of pictures to come......

ITEM WIRE COLOUR/Color Location

Turn Signal (Left) BLUE Passanger Kick, Harness to Rear
Turn Signal (Right) BLUE W/Red Stripe Passanger Kick, Harness to Rear

Ground located at Passanger Kick, BIG SCREW.... with wires


Pics to follow.. im lazy now and still doing the install, also, ALWAYS CHECK WIRES BEFORE tapping into them, you never know when they are going to change!!!
 
any reason why getting the CX-9's accessory mirror turn signals kit and swapping the parts over to the CX-7 mirrors wouldn't work? the mirror designs are basically the same, it's just the mounting base that goes on the door is different
 
A Purdy Install!

A revised version from the Thread Starter, Including Install Shots

Time: 2 hours
Difficulty: Moderate

Supplies:
Flathead screwdriver
Philips Screwdriver
10mm Wrench/Socket
16-18 gauge wire Black/Red... (Approx 25-35 ft)
Coat hanger (or your favourite wire snaking tool)
Electric tape
T-tap connectors (2) w/Spade Connection
Heat Shrink
Solder
Heat Gun
Soldering Iron/Torch
Spade Connectors (2)

Step 1: Disassemble the Mirror

a) Begin by popping off the mirror from it's gimbal. To do this push the mirror "down and away" from the car and pull from the top corner closest to the car. The plastic ball-and-socket should then dislocate. There are two fat plastic rods also connected to the mirror which control it's position - do NOT pull them off. With the mirror off its gimbal you'll be able to see the clips for the front cover behind it.

Top Left and Right of Mirror Housing, Push these clips down, once you do the cover should almost pop off

b) Remove mirror cover. Using a screwdriver push the clips for the front cover through their holes and pull on the cover from the front side. Frankly, this is where you can just go nice and slow and save your OEM covers should you want to reinstall them; so broken clips are not such a good idea. With the cover removed you'll quickly realize that snaking the wires through to the wiring harness in the car is a joy factor of 10

d) Remove inside door trim near mirror. This mostly rectangle piece of plastic simply pops off with gentle force. Don't worry, there is just one clip and it is pretty durable, but be nice to your M3.

e) Unbolt the mirror from the door. After you remove the trim per the previous step you'll notice three bolts. Unbolt them and pull the plastic trim from the outside.

With these steps complete you'll see how you need to route the wires into the door.

Step 2: Route Wire to Car Body

DSCN4160.JPG


This step is straightforward. With the mirror-disassembled run the wire through the centre hole of the mirror hinge following the Heater/Power Mirror wires from the mirror to beside the white Heater/Power Mirror connector.

DSCN4163.JPG


At this point you can reassemble the LED Cover and Mirror and reattach to the vehicle, making sure to fish the wiring beside the white connector and through the hole.

DSCN4152.jpg


Once the mirror is reattached, run the wire along the existing loom down the door and down to the rubber conduit where all other wires lead to the car body. This is a double 90, its easiest if you pop the clips on the top and bottom of the plastic Harness on the door side and snaking the wires through the door wiring harness, once the wire has been run into the vehicle you can re-assememble this cover/gasket

DSCN4166.jpg


At the body, remove the black rubber cover, you will find a hole on both the drivers and passengers side to snake the wires into the cabin, this rubber boot is a pain to get back on, start by first popping the four clips (2) top and (2) bottom and pulling the white harness out about 1/2 inch, proceed to put the rubber harness back onto the white plastic by starting on the engine, or backside of the connector and working your way around to the side facing you.

Step 3: Route Wire to Passenger Kick harness

DSCN4170.JPG


Start by removing the Glove Compartment, and drivers side panels mentioned below, to remove the glove compartment, first remove the Carbon Fibre cover by popping it off starting on the drivers side, the very end is slid into a notch at the top right side of the glove compartment, once this is removed, unscrew the 2 screws shown below and pull out the glove compartment.

DSCN4168.JPG


Now you have a choice. Ideally you should route both the drivers ground and 12v wire from the drivers turn signal to the Passenger side, or you can ground the ground wire somewhere on the driver’s side.

DSCN4169.JPG


My initial wiring from the drivers turn signal made it through to an area just above the OBDII port, I then soldered, and shrink tube these connections and fished the wires through the dash to the passenger side by popping the instrument cluster lower drivers dash panel and centre vent covers.

DSCN4165.JPG


Step 4: Tap Wires into the Turn Signal

TEM WIRE COLOUR/Color Location

Turn Signal (Left) BLUE Passanger Kick, Harness to Rear
Turn Signal (Right) BLUE W/Red Stripe Passanger Kick, Harness to Rear

Ground located at Passanger Kick, BIG SCREW.... with wires

The easiest way to identify them is to look for a blue and blue-red striped wire at the passengers kick panel, this wiring comes from the fuse panel, and routes down to the floor, heading towards the rear of the car. You can tap into the Blue and Blue/Red ones at any point using t-tap connectors.

DSCN4155.jpg


BEFORE TAPPING INTO ANY WIRING, TEST WIRING USING A MULTIMETER FIRST!!! then.... DISCONNECT THE BATTERY!!, Airbags suck when they deploy or go to a fault State!

Connect the male spade connectors to the wires you ran from the drivers and passenger doors, and then plug them into to the t-taps, connect the grounds together and crimp on a suitable end to connect to the ground point located next to the wiring on the passenger lower kick area.

Step 6: Tape-off/Zap Strap Wires and Reassemble Everything

DSCN4160.JPG


You'll need to tape/zap strap the loose wires along their path from the door to the wiring harness, I prefer using tape in doors and zap strap everywhere else to avoid annoying buzzing from rattling zap straps. Then reassemble everything.

A truly professional install doesn’t use butt connectors, or run bare wire into the engine compartment.
 
Last edited:
Heck I would think that it would've been easier to disconnect the mirror run cable from there through the door rubber boot then fish it out to engine area and run the cable and tap the wires at the head lamp level. Access to this area would be the same as changing the headlight bulb which requires to turn the wheel in and pull out the inner wheel cover and bam theres the wires right in front of you.
 
A revised version from the Thread Starter, Including Install Shots

Time: 2 hours
Difficulty: Moderate

Supplies:
Flathead screwdriver
Philips Screwdriver
10mm Wrench/Socket
16-18 gauge wire Black/Red... (Approx 25-35 ft)
Coat hanger (or your favourite wire snaking tool)
Electric tape
T-tap connectors (2) w/Spade Connection
Heat Shrink
Solder
Heat Gun
Soldering Iron/Torch
Spade Connectors (2)

Step 1: Disassemble the Mirror

a) Begin by popping off the mirror from it's gimbal. To do this push the mirror "down and away" from the car and pull from the top corner closest to the car. The plastic ball-and-socket should then dislocate. There are two fat plastic rods also connected to the mirror which control it's position - do NOT pull them off. With the mirror off its gimbal you'll be able to see the clips for the front cover behind it.

Top Left and Right of Mirror Housing, Push these clips down, once you do the cover should almost pop off

b) Remove mirror cover. Using a screwdriver push the clips for the front cover through their holes and pull on the cover from the front side. Frankly, this is where you can just go nice and slow and save your OEM covers should you want to reinstall them; so broken clips are not such a good idea. With the cover removed you'll quickly realize that snaking the wires through to the wiring harness in the car is a joy factor of 10

d) Remove inside door trim near mirror. This mostly rectangle piece of plastic simply pops off with gentle force. Don't worry, there is just one clip and it is pretty durable, but be nice to your M3.

e) Unbolt the mirror from the door. After you remove the trim per the previous step you'll notice three bolts. Unbolt them and pull the plastic trim from the outside.

With these steps complete you'll see how you need to route the wires into the door.

Step 2: Route Wire to Car Body

DSCN4160.JPG


This step is straightforward. With the mirror-disassembled run the wire through the centre hole of the mirror hinge following the Heater/Power Mirror wires from the mirror to beside the white Heater/Power Mirror connector.

DSCN4163.JPG


At this point you can reassemble the LED Cover and Mirror and reattach to the vehicle, making sure to fish the wiring beside the white connector and through the hole.

DSCN4152.jpg


Once the mirror is reattached, run the wire along the existing loom down the door and down to the rubber conduit where all other wires lead to the car body. This is a double 90, its easiest if you pop the clips on the top and bottom of the plastic Harness on the door side and snaking the wires through the door wiring harness, once the wire has been run into the vehicle you can re-assememble this cover/gasket

DSCN4166.jpg


At the body, remove the black rubber cover, you will find a hole on both the drivers and passengers side to snake the wires into the cabin, this rubber boot is a pain to get back on, start by first popping the four clips (2) top and (2) bottom and pulling the white harness out about 1/2 inch, proceed to put the rubber harness back onto the white plastic by starting on the engine, or backside of the connector and working your way around to the side facing you.

Step 3: Route Wire to Passenger Kick harness

DSCN4170.JPG


Start by removing the Glove Compartment, and drivers side panels mentioned below, to remove the glove compartment, first remove the Carbon Fibre cover by popping it off starting on the drivers side, the very end is slid into a notch at the top right side of the glove compartment, once this is removed, unscrew the 2 screws shown below and pull out the glove compartment.

DSCN4168.JPG


Now you have a choice. Ideally you should route both the drivers ground and 12v wire from the drivers turn signal to the Passenger side, or you can ground the ground wire somewhere on the driver’s side.

DSCN4169.JPG


My initial wiring from the drivers turn signal made it through to an area just above the OBDII port, I then soldered, and shrink tube these connections and fished the wires through the dash to the passenger side by popping the instrument cluster lower drivers dash panel and centre vent covers.

DSCN4165.JPG


Step 4: Tap Wires into the Turn Signal

TEM WIRE COLOUR/Color Location

Turn Signal (Left) BLUE Passanger Kick, Harness to Rear
Turn Signal (Right) BLUE W/Red Stripe Passanger Kick, Harness to Rear

Ground located at Passanger Kick, BIG SCREW.... with wires

The easiest way to identify them is to look for a blue and blue-red striped wire at the passengers kick panel, this wiring comes from the fuse panel, and routes down to the floor, heading towards the rear of the car. You can tap into the Blue and Blue/Red ones at any point using t-tap connectors.

DSCN4155.jpg


BEFORE TAPPING INTO ANY WIRING, TEST WIRING USING A MULTIMETER FIRST!!! then.... DISCONNECT THE BATTERY!!, Airbags suck when they deploy or go to a fault State!

Connect the male spade connectors to the wires you ran from the drivers and passenger doors, and then plug them into to the t-taps, connect the grounds together and crimp on a suitable end to connect to the ground point located next to the wiring on the passenger lower kick area.

Step 6: Tape-off/Zap Strap Wires and Reassemble Everything

DSCN4160.JPG


You'll need to tape/zap strap the loose wires along their path from the door to the wiring harness, I prefer using tape in doors and zap strap everywhere else to avoid annoying buzzing from rattling zap straps. Then reassemble everything.

A truly professional install doesn’t use butt connectors, or run bare wire into the engine compartment.
why is your post in THIS thread which is for CX-7s?
make your own thread in the mazda3 section!

and also, there is an OEM kit you can get that makes life a lot easier for the 3s
 
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