If you want to know if your alternator is performing, start the engine, open up the battery caps and check to see if there are any bubbles rising from the plates. If there aren't any, it could possible mean your alternator isn't functioning. I learnt this the hard way.

I made an overseas trip a few weeks back and left my car at homw without disconnecting the battery, absence of mind. The car was left unattended for 7 days. I started the car the day I came back and it fired up on first crank. Took it for a spin to recharge the battery and no problems at all. Next morning drove to work and it stalled in the middle of the highway.

After 15 minutes of driving witour any signs of trouble, I lost the speedometer, then the odometer, then the radio, the air conditioner, turbo and acceleration power. I sensed soemthing was wrong and I should have pulled up by the side of the road but decided to push my luck and got the worst.

Called up "Volvo on Call" service and provided them the symptoms before it stalled and they suggested it could be the battery, confirming my suspicion earlier. Took my chances and repalced it with a brand new battery by myself. The car started and everythign else worked fine and I drove straight to work.

After work, not suspecting anything else, took the car out out of the buidling and drove home. The $@# car stopped in the middle of the road again!!!!! At this point, I really thought I was going to change it to a Toyota or someother make that could be slightly more reliable.

I had the car towed back to the service centre and found the alternator to be malfunctioning. Replaced it at the cost of some 700 USD (with belt, pulley, tensioner). In the last two years, I have replaced the following un-scheduled items:

1. ABS module
2. EMS Module
3. Alternator

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I installed a grounding cable kit (cost me around 40USD)to my S70 2.0T and observed a "noticable" improvement to my car's performance (pick-up, radio reception, etc.) The fuel consumption was also lighter (it was abvious from the trip computer, down from 11.5 to 11.1).
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