The term AFS is used in the 2nd diagram to help differentiate between the bulb type turn signals vs the led type.

I'm trying to swap my headlights(without-AFS) to a higher trim version(AFS) on my 2018 Mazda CX-9 Touring. So far installing the higher trim headlight has been plug and play and everything works except the turn signal does not activate at all. I've never looked at an electrical diagram before and having trouble understanding what I'm looking at.

In the first diagram below, my vehicle's original headlight has "BULB TYPE" turn signals which is easy enough to understand: there is a "hot" wire and a ground wire.

However, the higher trim headlights utilize "LED TYPE" turn signals and I don't understand why it has two "hot" wires.

My vehicle is missing the B+ wire from the engine fuse box which I believe is a constant 12v even with engine off. I tried adding a connection from the fuse box that has a constant 12v to where the missing wire should go but this did not work. I'm also curious what does the dashed line mean in the 2nd diagram that connects the GY/L(F) to the GY(F) wire. Thanks in advance.

Turn Signal Electrical Flow Schematic Electrical Flow

  • \$\begingroup\$ What does AFS mean? Would this question be more suited for an automotive SE? \$\endgroup\$
    – Hearth
    Jul 5, 2019 at 2:20
  • \$\begingroup\$ AFS is Mazda's proprietary Adaptive Front-lighting System that will adjust the angle of the headlight beam based on steering. I don't think this affects the turn signal wiring, I just included that terminology since it's also used in the 2nd diagram to differentiate between lower and higher trim headlights- lower trim models have non-AFS headlights which use bulb type turn signals. \$\endgroup\$
    – dongali
    Jul 5, 2019 at 2:54

1 Answer 1


I figured out the turn signal wiring! The headlight simply required two B+ inputs.


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. https://i.imgur.com/PD8dwvN.png

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, to the white/black wire and the blue wire.

Engine Fuse Box Diagram https://www.autogenius.info/mazda-cx-9-from-2016-fuse-box-diagram/


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