Hi guys, I'm undertaking a project to replace the boring Touring headlights on my CX-9 with the Grand Touring/Signature headlights. I plan on documenting everything as this will probably also apply to the CX-3, CX-5, and maybe even the Mazda6 and Mazda3.

The headlight swap/upgrade from sport/touring to Grand Touring seems very possible and almost plug and play for basic functionality including the LED DRL ring accent. However, the turn signal does not work and you will get hyper flash. I'm guessing this will be a easy fix if I can find the turn signal wire in the harness that I can tap into. The hyper flash will likely need a typical resistor to trick the blinker relay unit. Or it might be possible to replace the blinker relay with the GT's?

For now, I'm just stuck at figuring out how to tap into the turn signal wire in the GT headlight wiring harness. If we can get the turn signal working, we can then start on figuring what's needed for the adaptive lighting.

Any help in finding the turn signal wire or the headlight wiring diagram is greatly appreciated, cheers.

Parts:
Headlights from Grand Touring CX-9 (may find some good deals for used GT/Signature headlights on eBay)
2x Wire Harnesses from Grand Touring CX-9 (PN: TK-50-51-0K6 about $40ea + tax/shipping)

Working:
LED DRL accents
low beam
high beam
side markers
turn signals (requires minor wiring)

Not Working:
adaptive lighting

How to:
1. Remove front bumper and grill Instructions Here
2. Disconnect both headlight wiring harnesses
3. Remove both headlights
4. Connect the GT/Signature headlight wiring harnesses
5. Install the GT/Signature headlights
6. Reinstall front bumper and grill









Wiring harnes

 

There are no relays, its all controlled from within the F-BCM.

 

The diagrams below shows the electrical flow that activates the right turn signal. As you can see, in the AFS headlights, it has an additional gray wire, labeled GY(F), compared to the non-AFS headlights. I tried adding a wire connection from the white/red, labeled as W/R, to where the missing gray wire should be but that doesn't work. Maybe the B+ wire in the 2nd diagram means a constant 12v and missing gray wire is a constant 12v where the white/red switches it? Theoretically I should be able to activate the turn signal by powering the LED as it does not require any CAN/DATA wire.




NOTE: AFS headlights use LED (Grand Touring and Signature trims)
non-AFS headlights use Bulb Type (Sport and Touring trims)

 

I figured out the turn signal wiring!

The Grand Touring and Signature headlights require 2 constant 12v inputs for each side of the front turn signals which the Sport and Touring harness is missing.
What I did to test this theory was wire an always on 12v to the 2 wires- white/black wire and blue wire on the GT/Signature harness that I purchased, PN: TK50-51-0K6.

The wire color of the engine harness differs from the headlight harness. The white/black and blue wires on the GT/Signature harness connects to the Gray wire on the engine harness.


There is an always on 12v at position 50 in the engine fuse box, which was also originally for the hazard and front/rear turn signals.

Engine Fuse Box Diagram
https://www.autogenius.info/mazda-cx...e-box-diagram/

 

This helps quite a bit. Ive been thinking of doing the same thing on my wife's Touring model but I didn't think it would be possible to get all the basic light functionality without software changes. Thanks for the write up