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Subwoofer installation guide

502 Views 1 Reply 2 Participants Last post by  Tony1
Hi everyone,

In this post I will explain how to install a Subwoofer in a Volvo V40 with the Harman & Kardon System.

  • Connecting to the OEM Amplifier
  • ACC wiring
  • Wiring diagram
  • My results
Connecting to the OEM Amplifier
The Harman & Kardon OEM amplifier is located under the left seat (LHD model). It has a 16 pin connector with the following layout:
Circuit component Rectangle Hardware programmer Font Audio equipment

  1. Grey/Black | Front Left -
  2. Grey | Front Centre -
  3. Yellow/Black | Front Right -
  4. Grey/Red | Rear Left -
  5. Yellow/Red | Rear Right -
  6. Switched 12v ????
  7. Empty
  8. GND ???
  9. Green/Black | Front Left +
  10. Green | Front Center +
  11. Violet/Black | Front Right +
  12. Green/Red | Rear Left +
  13. Violet/Red | Right Rear +
  14. Empty
  15. Empty
  16. Antenna power ???
Make sure your aftermarket amplifier accepts high-level inputs. Or buy an high-to-low converter.
I never like to cut OEM wires so I ordered this kit. It has the 16 pin connector which can be mounted in between the OEM connector and the OEM amplifier.
I did cut the front speaker wires of the kit and mounted RCA adapters to the wires. The RCA adapters can ordered here.
Then I ran a RCA cable to the trunk like displayed on the wiring diagram at the at of the post. The RCA cable can be ordered here.

ACC wiring
The Volvo V40 has no real ACC. Instead I bought this. It is a DRL module. It reads the voltage and when the voltage is higher then 13 it turns on. The module has 5 wires which you connect to:
  1. Battery + | Connect to 12v cable of aftermarket amplifier
  2. Battery - | Connect to 12v power cable of aftermarket amplifier
  3. DRL + | Connect to acc of aftermarket amplifier
  4. DRL - | Don't connect
  5. Headlight wire | Don't connect
Wiring diagram
Vehicle Hood Automotive lighting Motor vehicle Automotive design

The thick 12v cable is connected to the battery. Ran it through the firewall. The firewall has a rubber I drilled a hole in for the thick cable. The rubber is on the right side of the car behind the storage box. Then I ran the cable to the back of the car, hidden behind the trim.
The thick GND cable is connected to one of the bolts that mount the rear seat.
The RCA cable is connected to the OEM amplifier as explained in chapter 1. The RCA cable runs under the carpat and is hidden behind the plastic trim.

My results
Car Vehicle Automotive lighting Hood Vehicle registration plate

I think the results speak for themself. Let me know if this guide is missing anything!
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