Hi Everyone,

I just ordered an aftermarket head unit. I got the XTRONS TM100L. (https://xtrons.co.uk/single-din-doub...oid-8-1-tm100l) I was looking to see if anyone knew what wiring kit I would need to connect it to my c5. I want to keep the factory bose speakers working with this unit as well and will upgrade them later on. But until then, I would like the factory amp powered speakers to work with this aftermarket head unit. Would I need any other required hardware?

Thanks so much!

 

There's no way around having to use an interface to properly replace the OEM headunit, keeping the rest of the system intact. This interface is not a simple wiring harness, and it is needed because the C5 Bose system doesn't use standard signals.

This system is based on a modified Delco head-unit, a Bose DSP box and subwoofer amps that use pseudo-differential low level signals along with fully differential speaker level signals. The common signals are not standard and have a DC offset, so they cannot be grounded.
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The 2 most commonly used interfaces are:

• AXXESS XSVI-2004
• PAC AUDIO ROEM-VET1

Either one will perform well when correctly installed, although the Axxess offers better system integration as a result of interfacing with the Serial Data Bus. That's why the difference in price.

Since the interfaces with the Serial Data Bus, in addition to preserving the Retained Accessory Power (RAP) feature, it does not need an external "Accessory" switched power connection.

Because the

Pac Audio ROEM-VET1

Pac Audio ROEM-VET1

doesn't interface with the Serial Data Bus, it doesn't preserve RAP and requires the extra switched connection mentioned above. The headunit's OEM harness lacks this connection, but it can be easily brought from an unused harness (except '04) in the passenger's footwell that has 3 wires (yellow: switched via Fuse 11, orange: always hot via Fuse 7 and black: ground).

The Retained Accessory Power (RAP) Feature allows the radio to continue playing for approximately 10 min or until a door is opened, whichever happens first, after the ignition switch is turned off.

These adapters take care of all necessary interfacing and make the process plug-and-play, while preserving the OEM wiring.

Here is a diagram showing a replaced headunit while keeping the rest of the system intact (the diagram is the same for AXXESS or PAC adapters). ​​​​​​