2007 Honda C-RV; Query regarding brakes

[Boselecta]

I've owned car since March. All 4 wheels have disc brakes. Three of the wheels get dirty with brake dust but one doesn't.
After a month or so of this I telephoned Honda dealer & siad I was concerned that my offside rear brake wasn't working properly as the wheel was spotless & not creating any brake dust (although I admitted that there was no other problem like veering or anything).
They said they'd never heard of such a query before but nevertheless suggested I bring the C-RV in for a check. I did that & they found no fault - this reassured me things were OK.
Anyway, moving on several weeks later to today. I just washed car/wheels for first time for a month (weather's been too foul) & the three other wheels were black with brake dust & the "faulty" one remains pristeen & free of any dust at all.
This has really got under my skin now - surely there must be a problem with the brakes on this wheel? Can anyone suggest either:
a) Why the rear offside wheel is not generating brake dust
b) or reassure me it's normal/fine
Cheers!

 

[freddiemercurystwin]

Assuming you're not afraid of getting your hands dirty, you could jack it up and spin the wheel and then apply the brakes, that would be the first thing to do, secondly you could whip the wheel off and check if the pads are as worn as the working side, presumably the disc's shiny and not rusty? Have a look and report back. Alternatively take it to another garage. Or get an MOT tester to do a brake test.