Auto Battery Replacement and Testing PAC003

In today’s episode Neil and Dave present how different auto battery replacement is on newer vehicles and why you need to let a professional change it. We also discuss why it should be changed before it fails.

Most of us have surely noticed how our vehicles have become loaded with electronics. We know we can’t work on them like we could in the past. But most of us would think we could still do something as simple as changing a car battery. As we will hear from Neil, that is not the case for newer vehicles.

First lets talk about batteries ratings. Most batteries are rated by the manufacture to last 4, 5, 6, even 8 years. In our area of Twin Falls County and southern Idaho, battery life in our cars is between 3.5 to 4.5 years, regardless of its rating. The reason is because of the dramatic temperature swings Twin Falls has, like 100 degrees during the summer and cold temperatures in the teens to zero during winter. Those extremes shorten a batteries life.

Batteries are also much smaller than in the past and they are matched to the vehicles electrical and electronic systems. Any repairs or replacements require caution to avoid causing problems with computer programming.

An auto owner could have a problem with their battery and not even know it. He talks about the reason we should replace a battery even though the car is still starting and showing no symptoms.

All vehicles coming into Palmer’s Automotive Repair get the battery tested. Today’s cars and trucks have so much electronics, so many computers, and many more lights inside and out, than they did in the past. Batteries and alternators have flipped functions. Batteries are smaller and alternator outputs have increased dramatically.

In the past cars used 12-volt systems and had alternators that charged up to 35 amps. Now we have vehicles that are running 48 volts and 150 amps.  If we have a battery that is not working at or near 100% it can prematurely wear out alternators, starters and sensors.

Case study of a simple battery replacement going bad

In November 2018 a 2012 Ford car came in for regular maintenance services. After checking the vehicle we informed the owner of several maintenance items that his car needed. One item was a weak battery that they needed to be replaced.

Customer stated he could take care of the battery replacement himself. In January 2019 he had a battery problem and changed it himself. After changing the battery he had very strange conditions like having the door locks and wipers going on and off by themselves. The dome lights would not turn off unless he pushed the manual override switch. The car had also become hard to start.

Disconnecting the battery and installing the new one caused the cars computers to become confused. The memory and programming was lost. The vehicle was returned to Palmer’s to have the problems fixed. The total cost to get a new battery has now almost doubled because the computers have to be reprogrammed.

Neil pointed out the importance of replacing batteries with the same type that came out to avoid future problems. A battery with the wrong capacity should not be installed in newer vehicles. The electrical system is designed for exactly one type and size of battery.

Battery Jumper Cables

Use caution when jump starting your vehicle

Here is the proper procedure to follow when jump starting your vehicle:

  1. The first step is to read your car’s owners manual and follow the manufactures procedures
  2. Turn off the vehicle being used to jump the dead car
  3. Insure both vehicles have the ignition switches in the off position
  4. All jumper cable connections will be from positive to positive and negative to negative
  5. Hook the jumper cables up to the dead battery positive cable and its negative cable
  6. Next hook up the positive cable to the positive battery post on the jump vehicle.
  7. The last connection is to the negative battery post, or a good ground point on the jump vehicle.
  8. Once all connections are made, start the jump vehicle and increase the engine speed for a few minutes. This is especially important if the cars dead battery is drained completely. This allows the dead battery to get some surface charge before trying to start it.

If this procedure is not followed it could cause damage to the electronics of the vehicle being jumped, and possibly damage the jumper vehicles electrical or electronic systems.

Another common problem on autos is corroded battery cables. Dirty cables should be cleaned because the contamination can leak energy out of the battery. This leakage can drain a battery and dirty cables are frequently the cause of a vehicle not starting due to a poor connection.

If you have a vehicle that is 1995 or newer you should be careful of replacing your own battery. You may save money by having a shop install a replacement to avoid damaging electronics and computers.

Corroded Battery Cables

Conclusion about car batteries

Don’t assume your current vehicle is like the one you had previously. New vehicle electronics has exploded in popularity on newer vehicles. Electronic components and computers are expensive to replace, and as we described, computer programming can be damaged by incorrect battery replacement procedures.

If you need help with testing or replacing a battery on a car or truck newer than 1996 just give us a call at Palmer’s Automotive Repair in Twin Falls. If you live close to Kimberly you can stop by the Vehicle Service Center. We test and replace batteries there, and we use the same quality NAPA batteries.

Key takeaways from this battery episode:

  • Car batteries last 3.5 to 4.5 years in Twin Falls and southern Idaho
  • Do It Yourself (DIY) battery replacement can cause electronic problems
  • Newer vehicle can have 48 volt electrical systems with 150 amp alternators
  • Use caution when jump starting dead batteries with another vehicle
  • Dirty battery cables shorten battery life and can cause no start conditions

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