Lambda Sensor and other problems

Hi all, Just wondering if anyone can tell me the answers to the following: Car is a 2001 S80 2.0t, purchased in april with a 3 month "engine and gearbox" warranty. Query 1. last week got a message saying "emissions system service required", took to local independant volvo specialist and he said that the lambda sensor is gone and should be covered under warranty. Spoke to garage where purchased and he says is not part of "Engine" and is not covered. Question is this - is the lambda sensor considered part of the "engine"? if not how much is this likely to cost to replace? Query 2. Was in our local town yesterday and the car was parked as you do normally, however when i went to put some of SWMBO purchases in the boot and move the car to a more suitable position nearer the latest plastic melters! when i opened the drivers door the air con system was on and running and a message reading "alarm activated check vehicle" was displayed. Question is has anyone out there had this happen to them before? Your thoughts would be appreciated. Regards, :star-wars-smiley-00

Questions 

The lambda probe or oxgen sensor is fitted in the exhaust so I suppose technically is not part of the engine. However it is part of the engine management system so I suppose it is down to interpretetion. You second query has two parts. On returning to the car you say the a/c was on, I presume you meant the interior fan. If this is the case this is perfectly normal and is called by Volvo the 'afterblow function'. This is controlled by the ECU which determines you have used the a/c which in turn activates the interior fan periodically to try to 'dry out' the interior of the heater box in an effort to reduce the effects (smells) caused by stagnant water. The alarm activated message normally is posted when the alarm has been activated (funnily enough) but has then re-set itself. So either your alarm was activated by something ie heavy vehicle passing close (can happen if cabin sensor over sensitive) or there is a fault in your alarm system. Paul.

Thanks Paul, Was only wondering if it may have been an electrical fault and the alarm system had somehow triggered the fans, never knew about the 'afterblow', handy feature that. Was also beginning to think that the car was being intelligent and was cooling down the interior for me before i sat in as it was quite warm. At least nothing to be "alarmed" about!!!! Cheers :star-wars-smiley-00

it comes on after 40 mins 

on my 2001 s80 anyway, takes abit of getting used to, people sometimes stop and look at the car that seems to start up on its own! neighbour knocked once to tell me car was running!