Technical info about wiring harnesses

PCM 2.1 (Navigation Screen) cars will almost always have a fiber optic amplifier.  There are very rare early models that have a PCM but not fiber optic amplifier audio. In the hundred or so cars I’ve worked on and hundreds that I’ve sold parts to I’ve only seen it a handful of times.  CDR-24 cars usually only have fiber if the car has Bose.  Some Boxster and Cayman cars may have PCM and no Fiber. Even though the audio system is the same I do not see too many of them because until now we never added them to the site.  Put your vin number into the order comments and we can verify if your car has a fiber optic amplifier.

The small box on the main harnesses is a CAN-BUS data reader.  It reads for switched 12V, illumination, parking brake, reverse signal and Vehicle Speed Sense.  I have seen some 911 not provide VSS and I have seen a few Boxster models not provide reverse.  If they car does not provide it on the CAN-BUS data wires my box cannot provide it.

The large Box with knobs is our HILO box.  The box adjusts the audio levels going into the the factory amplifier.  Since different radios have different outputs this is important.  The box has four knobs only the front ones will l be used during installation.  And yes it will keep all your speakers just not the fader.  No adapter on this planet keeps your fader.  We also have the fiber harness without the HILO box. This will sound a little less than factory.