I had an intermittent problem with range, seemed like a bad contact on the
aeial but never really tracked it down.  Could also have been  key fob
batteries which have now been replaced, even though both key fobs failed to
work.  It hasn't occured again.  Possibly also could have been wetness from
the leaky sunroof, also now fixed.

During the problem I found the car more receptive near the RHS wing
indicator, and with the car unlock and alarm going under the dash. (UK /
right hand drive).

One time I couldn't get the alarm off and Volvo gave me some waffly
instruction to remove 2 fuses, but the main  thing I found was to disconnect
the sounder on the front left suspension dome, and disconnect and reconnect
the battery.  This allowed the car to be used, as the immobiliser can't know
if the engine is on or not and musn't immobilise in this case as it would be
dangerous.  I think the hazards were going but stopped eventually.

--
Tony Stanley