Possibly, but it depends on your system...

There are three versions of the audio systems. The standard system uses the amp built into the radio to power the speakers. The "HiFi" system has a separate amp in the trunk to power the speakers, and the "Top HiFi" system has the more powerful DSP amp in the trunk.

Since you say that you have the 6 speaker setup, you probably have the standard stereo, in which case you can tap into those outputs to feed your sub amp.

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