PAC LPHGM51 LocPro Advanced T-Harness

Upgrade your GM-built radio

Adding an aftermarket amplifier will beef up the sound of any audio system, even when you can't replace the factory radio. PAC's LPHGM51 LocPro Advanced T-harness makes amplifier installation a lot easier by giving you access to the speaker-level output signals from your GM-built factory radio. You can use this T-harness to connect to an amplifier or signal processor with speaker-level inputs, or to a line output converter with an amp.

Provides signal for your system

PAC designed this vehicle-specific T-harness to work with their LPA LocPro Advanced line output converters, but it'll also work with almost any sound processor or line output converter, as well as most amplifiers with high-level inputs. The harness also supplies the connection wires for low-power constant 12 volts (fused for your protection), accessory power, ground, and remote turn-on leads for a system device like an active signal processor.

Note: The power and ground wires in this harness will only support a low-current accessory, like an active line output converter or digital signal processor, and should not be used to power an amplifier.

How it works

First, you unplug the radio and install the T-harness. Two T-harness plugs go into the radio, the others snap into the plugs you just took out. You're then left with the radio still completely connected to your vehicle, with the addition of a pigtail of wires to use for adding an amp.

Adding a subwoofer amplifier

The T-harness pigtail includes four speaker-level channels — eight wires — that you can use to provide the input signal for a subwoofer amp or powered sub.. The amplifier will have to get its power and ground connections separately. The factory radio will still run all the speakers.

For powering the entire system, you'll need to do some rewiring

You can add a 4-channel amplifier to your system by using all four of the T-harness's speaker-level channels for your aftermarket system's inputs. PAC has made provisions in this harness for sending your aftermarket amplifier's outputs back through the factory wiring and on to the speakers. The appropriate wire bundle has clearly marked labels showing you which wires to disconnect and where, and which wires you'll need to connect to your aftermarket amplifier's outputs.