It has come to my attention that newer cars require a fully charged battery to run all of the computers - especially during engine start procedures!

While batteries are bigger and have more CCAs than ever before, any battery that is below 12V prior to engine start can cause a multitude of errors that appear to be unrelated. Climate control not working properly? ABS and traction control messages? Cruise control problems? Emmission problems?

I have 2 newer cars in my garage that are not Volvos, the 2008 started to give me strange driveability problems when it was cold started. After a brief 'warm up', an engine restart made the problems go away. A couple of months of this without any good resolution, the battery started to get too weak to start the car. I put the battery on a trickle charger because I only drive it a few times a month, and all was well until the battery ran down again. A new battery solved all of the nit picking problems!!

With the number of 'computers' on board these new cars, the ability of each computer to 'boot up' normally is compromised by a weak battery. These computers may not finish the boot up process due to lack of good steady voltage. Remember, the electricity from the alternator goes to the battery before it gets to the cars systems, and getting the battery back up to 12V may take some time.

So, moral of the story: Batteries no longer last 6-8 years or more. Some of the systems use battery voltage when the engine is off and the battery gets 'abused' by discharging and recharging a lot.

Don't wait when your battery gets 4-5 years old, just get a new battery when the resting voltage gets down to 11.9V or less.

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My back feels better when I sit in a Volvo seat