UTProgrammingNot programming a replacement battery for a car can cost you in the long run
UTProgrammingNot programming a replacement battery for a car can cost you in the long run

Not programming a replacement battery for a car can cost you in the long run

While cars requiring a battery replacement be registered or programmed have been around for quite some time in the European vehicle market with the more complicated German-engineered cars, this is now becoming more common for other manufacturers. That’s because tightening fuel economy standards are forcing all manufacturers to scrutinize any and all inefficiencies that may be occurring in a vehicle’s fuel management system.

The only job of the alternator is to charge the battery. Historically, the alternator did this with little fuss and fanfare. As the battery becomes depleted from routine use, the alternator, which is different from the starter motor, replenishes the battery.

An alternator is similar to a generator. It is driven by the engine using a belt and therefore uses a small amount of engine horsepower to do its job. Therefore, the longer an alternator is functioning and generating electricity, the more engine power it uses, and the more fuel it consumes. The extra amount of fuel being used is not much, but in this fuel-conservation environment everything, including complex battery and alternator management, is scrutinized. As a result, onboard management systems are more complicated than they were a couple of decades ago.

In order to save fuel, the Powertrain Control Module (PCM) via the Battery Management System (BMS) shuts off the alternator at every opportunity. As a battery ages, it will require the alternator to remain operating and charging for longer periods to ensure the car starts reliably and functions properly. A constant, albeit small extra load is now being placed on the engine compared to when the battery was new. Fuel conservation becomes a second priority to keep the battery charged when the battery is at the end of its life.

The primary purpose of programming or registering a battery is to verify that the PCM knows that a new battery has been installed. It needs to reset the vehicle’s charging characteristics, restoring the BMS system back to original state. Yes, in most cases your vehicle will run and function without the new battery being programmed, and yes you will be hard pressed to notice any difference in fuel economy.

When you used to buy a car battery from a retailer you were often offered a pro-rated five-year warranty. Now, most batteries only come with a three-year warranty. Everything in our retail landscape, from home appliances to electronic items, is made with cost savings in mind and car batteries are no exception.

The downside of not resetting the BMS system is that the life span of the replacement battery may be shortened as they are sensitive to being overcharged. If the BMS thinks the battery is aged, it will charge it for longer periods than necessary. While you may save a buck by not paying the additional cost to register your replacement battery, you will likely loose in the long run. Another battery replacement may be required sooner if you do not complete the battery registration properly.

To be honest I can’t understand why our complicated, robust contemporary vehicle management systems can’t detect a new battery without manual input from a technician, but that is a topic for another day.

Your automotive questions answered

Lou, I grew up riding in dad’s Porsche 912. When I was 33 years old, I bought a Porsche 911 996 model with a manual transmission, and I still have it to this day. When I got the 911, dad decided it was time to get his own dream 911. I told him not to sell the 912. He didn’t listen. He now regrets selling it.

Do not sell your 912. Figure out how to keep it. You have time, just figure it out. You need both. The old and the new. Trust me.

Matt D. – Rocklin, Calif.

Thanks Matt, I have no immediate plans to sell my 912, but I have a fair number of hobbies and afterward some overpriced toys. I feel guilty at times as I am aware that my money could be used elsewhere. I justify keeping it by looking at it from an investment perspective. It has doubled in value since I purchased it five years ago and is on its way to tripling in value. So, I’ll keep it for the time being and watch it go up in value all the while I enjoy driving it. What more could a gearhead ask for?

I have been enjoying your YouTube channels restoration of the Ferrari 308 GTS. I also own a 308 GTS and am curious about some of your repair procedures. I also see you are using a temporary blue protective film while working on the car. Can you tell me where I can purchase this item and what it is?

Thank you in advance. I am looking forward to hearing from you.



Hi Emilio, the blue film I used to protect the paint on my Ferrari 308 was purchased from a company called Wurth. The product code is 818.77054 and it can be purchased from their website shop.wurth.ca.

Open this photo in gallery:

Lou Trottier uses a blue film from Wurth to protect the paint while he works on his Ferrari 308 GTS in his shop, All About Imports, in Mississauga.Lou Trottier/The Globe and Mail

Lou Trottier is owner-operator of All About Imports in Mississauga. Have a question about maintenance and repair? E-mail [email protected]placing “Lou’s Garage” in the subject line.

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