Focus C-Max 2006. Owned for a couple of years now, and the rear speakers have never worked - I assumed they were just missing due to a low spec car. But I took the door card off last week and found a speaker there (with wiring as an added bonus too!). So I assumed there was a problem at the head unit ... just managed to get the CD6000 out (a task in itself) but all the wiring shown in the Haynes manual to the rear speakers is present and correct (Gy, Wh, Gy/Wh and Wh/Vt). 

Reading elsewhere I wonder if the rears have blown, but of course I didn't check the impedance while the door card was off ... I just assumed since both were dead it was something more systemic than both of them having just broken.

Any suggestions? Is my next step to get the door card off again and test there or is there something else to try first?

Does seem weird that they have both gone, are the rear speakers not got their own fuse? Perhaps the previous owner left the rear windows open on a rainy day I know this has happened to a few people at my workplace.

Does the CD6000 have a fader control, if so, make sure that it is centered! (My old Corsa had non-working rear speakers at one point after I owned it, due to the fader control set to the front and idiot brains here not realising!)

Broken (rear) speakers are pretty common on a Focus MK2/MK2.5. The speakers itself are not very high quality (they sound pretty decent however). They simply fail quite often.

Another problem can be a defective amplifier IC inside the radio. Both the Ford 6000CD and the Ford/Sony radio's that are used in the Focus MK2/MK2.5 use the same (Philips) amplifier IC. A defective amplifier IC is a known problem of these radio's. This can result in various symptoms. No sound at all (amplifier in protection mode) or defective speakers (usually the rear speakers) are just 2 examples. If the rear speakers broke down as a result of a defective amplifier IC a new pair of speakers will not last very long.

 

A few Years ago I repaired quite a bit of these radio's with a defective amplifier IC (mostly Ford/Sony radio's cause a 6000CD is not really worth the effort).