Volvo Repair: Volvo S80 signals, phillips head screws, volvo s80

Question
I have a 99 S80 and the turn signals will fail on me every few weeks.  I have found that as soon as I take the negative cable off the battery that they start to work again for a few more weeks.  What do you think is causing this annoying problem?
Thanks

Answer
Do they cut out all together or do they get intermittent (go fast, go out then back on, only one side).  If both directions fail and don't work at all then most likely your problem is the steering wheel module, which only a dealer can replace because it requires programming.  If they act up intermittently, most likely your problem is the turn signal switch itself.  They go bad all the time.  Easy to replace; you can do it yourself.  3 torx25 bolts holding the column cover on, then 2 phillips head screws holding the switch to the module.  Pull firmly, straight out, to remove it.  Be sure to not catch the airbag wiring while you're doing that (orange  insulation).

James