AUDM Subaru WRX STI (2016) Premium with Harman Kardon package

This information should be relevant for 2016-2018 models with the HK package. I’m unsure if there are any significant differences between the AUDM and USDM models.

On these 2016+ HK models the head unit outputs 2 channel line-level outputs to the amp and then sends commands to the amplifier/DSP to control the volume, fade, balance. The amplifier also handles the splitting of these 2 channels into the 9 required for the speakers.

For 2015 models the HK package followed a more traditional setup where the head unit was in control of volume/balance/fade and the amplifier simply amplified the signals it received.

Model number on the face of the head unit: FV242KS

Only the 28 and 10 pin are required to get audio and have the HU basic functions work.


Stock Head Unit

28-pin

Pin

Color

Description

1

2

Brown/Yellow

Reverse signal (12V)

3

Brown

Illumination Dimmer Cancel (Bright mode)

4

Grey/Blue

Mic amp power supply (5V)

5

White/Black

Mic audio input (+) twisted with pin 19

6

Black/Blue

Mic detect

7

Yellow/Blue

HK Amp TX (+)

8

Blue/Red

HK Amp TX (-)

9

10

11

12

13

14

15

Grey

Parking brake signal (<1V)

16

Black/White

Mute

17

Pink/Green

Vehicle speed pulse signal

18

19

Purple/Red

Mic audio input (-) twisted with pin 5

20

21

Brown/Black

SWC1 (+) steering wheel controls (vol, seek, list, return)

22

Blue/Yellow

SWC2 (+) steering wheel controls (mute, talk, source, on/off hook)

23

Yellow

SWC (-) steering wheel controls ground

24

25

Red

Aux detect

26

Black

Aux in right (+)

27

Grey/Yellow

Aux left/right ground (-)

28

White

Aux in left (+)

8-pin

This plug is for vehicles with the telematics module, AUDM cars don’t have this.

5-pin

Appears to be the reverse camera.

Pin

Color

Description

1

White

Ground

2

White

CB+ (6V power)

3

Red

Camera video (+)

4

Black

Camera video (-)

5

SVXdc makes a harness

https://forums.nasioc.com/forums/showpost.php?p=45327027&postcount=1271

10-pin

This 10-pin is sometimes referenced with the 6-pin below as a “16-pin”. Simply add 10 to the pin numbers of the 6-pin to get the equivalent pin number.

Pin

Color

Description

1

Red

? Line level right (+)

2

Black

? Line level left (+)

3

Yellow/Red

? 12V Accessory (+)

4

Blue/Red

? 12V Constant (+)

5

White

? Line level left (-)

6

Green

? Line level right (-)

7

Black/Blue

Ground

8

Yellow/Black

Antenna on

9

10

Purple

Illumination (+)

On non-HK vehicles, the line level outs (1, 2, 5, 6) are for the front channels.

6-pin

Pin

Color

With Harman Kardon

Without Harman Kardon

1

Rear right (+)

2

White

Interface box (+)

Rear left (+)

3

Rear right (-)

4

Red

SLD2

5

Black/White

Illumination (-)

Illumination (-)

6

Black

Interface box (-)

Rear left (-)

GPS

Markings on the connector: 50024 / PBT / HP8

This connector appears to be proprietary though has some similarities to a FAKRA connector.

AM/FM

Auxiliary input & USB Module

On the AUDM models this unit is under the head unit in the small pocket next to the 12V. I’ve seen information online suggesting that some USDM models have a single-USB inside the centre console.

USB

8-pin Aux

Pin

Color

Description

1

Black/Blue

Chassis ground from car

2

3

Grey/Yellow

Aux audio ground/shield

4

Red

Aux enable switch

5

Yellow/Red

+12V Accessory power (for USB power)

6

7

Black

Aux audio right

8

White

Aux audio left

Amplifier


24-pin harness


This harness appears to be primarily inputs - I’m guessing most of these wires don’t have a counterpart at the head unit end because there should only be ~4 wires for the inputs and ~2 for comms.

R316 (2009) / R386 (2010+)

https://stingeraustralia.com.au/product/mtaxtoycam36v/

https://www.amazon.com/dp/B01E4B6UQS/ref=psdc_10981131_t1_B01N8QJSK1

Pin

Color

2015

2016+

1

Black/White

2

White

Front left (-)

Left in (-)

3

Black

Front left (+)

Left in (+)

4

Green

Front right (-)

Right in (-)

5

Red

Front right (+)

Right in (+)

6

Black/Yellow

Shield ground

Shield ground

7

Blue/Red

?

? Amp/HU TX (-)

8

Yellow/Blue

?

? Amp/HU TX (+)

9

10

Black

Ground

EQ Select

11

Pink/Green

Vehicle speed pulse

Vehicle speed pulse

12

Light Blue

12V accessory - remote turn on

12V Accessory power supply

13-21

22

Green

Rear right (-)

Interrupt information (-)

23

Light Green

Rear right (+)

Interrupt information (+)

24


10-pin harness (blue plug)


Appears to be door speakers and amp power.

Pin

Color

Description

1

White

Battery power supply

2

Green/Yellow

Rear left door (+)

3

Blue

Front right door (+) Medium gauge

4

Green

Front left door (-) Medium gauge

5

White

Battery power supply

6

Purple

Rear left door (-)

7

Light Green

Rear right door (-)

8

Yellow

Rear right door (+)

9

Pink

Front right door (-) Medium gauge

10

Blue/White

Front left door (+) Medium gauge

The following harnesses should fit the car’s wiring should you want to remove/replace the HK amplifier:

12-pin harness

Appears to be high-pass outputs for tweeters and lowpass for sub along with grounding wires.

Pin

Color

Description

1

Yellow

Dash Tweeter Front Right (-)

2

White/Black

Dash Tweeter Front Right (+)

3

White/Blue

Dash Tweeter Front Left (-)

4

Black/Red

Subwoofer 1 (+) Medium gauge

5

Brown

Subwoofer 2 (+) Medium gauge

6

Black

Thick gauge - Ground

7

Black

Thick gauge - Ground

8

9

Black/Blue

Dash Tweeter Front Left (+)

10

White/Red

Subwoofer 1 (-) Medium gauge

11

12

Green

Subwoofer 2 (-) Medium gauge

The following harnesses should fit the car’s wiring should you want to remove/replace the HK amplifier:

Seicane Android Head Unit

https://www.seicane.com/hd-android-radio-capacitive-touch-screen-for-2014-2015-2016-subaru-forester-support-3g-wifi-bluetooth-gps-navigation-system-tpms-dab-dvr-obd-ii-aux-headrest-monitor-control-video-rear-camera-usb-sd

The head unit came with 2 primary harnesses, for my car we’ll be using the “Corolla power cable”.

171221-L
48-1-06245-0-10
“Corolla power cable”

20171221-X
48-1-06226-0-01
“Nissan/Subaru power cable”

28-pin, 10-pin, 6-pin, AM/FM

20-pin, AM/FM


Corolla harness

We’ll be using this harness for my vehicle (2016 WRX STI with HK amp)

Power and ground are 16AWG, most other wires are 20AWG.

It includes a few unterminated wires:

28-pin

Only 6 pins are populated:

  • 21, 22, 23 - Steering wheel controls
  • 26, 27, 28 - Aux in left/right/ground

10-pin

All pins except 8 & 9 are populated.

6-pin

All pins except 4 & 5 are populated.

AM/FM

Only one antenna plug is populated

Nissan/Subaru harness

Power and ground are 16AWG, most other wires are 20AWG.

It includes a few unterminated wires:

20-pin

AM/FM

RCA outs

2 x Video out, FR, FL, RR, RL and Subwoofer

AUX in

AUX-in left, AUX-in right, video in

Camera in

USB & Mic

2 x USB, Mic