Positive and Negative
By Butch Jones
I don’t think there are many people on the planet that are not aware of the fact that our lives are controlled by computers. It is more so for vehicles. The automotive computerization began I guess in the 1960’s with the “transistorized ignition” which was a system that used electronics to replace the mechanical components of an automotive distributor. It offered more powerful current and operated more efficiently over a broad engine speed range. The automotive industry has progressed to the point that your vehicle is “alive” even when the ignition is off and the key is removed. Since about the year 1977 automobiles have had computers, originally they were used as emission controlling devices and now they control everything from ignition, transmission shifting, spark advance, timing, air conditioning, tire pressure monitoring, security and the list goes on. The bottom line is that our vehicles use a lot of electrical current, both when we are driving and much less when they are parked.
It is during these periods of inactivity that issues can arise. Now this is not much of a concern for older coaches and towed vehicles, however, newer coaches and towed vehicles are highly susceptible to battery drain when not used.
Some of you may have a towed vehicle that is used mostly for towing behind your RV. If the vehicle sits for more than a week or so the battery may drop in voltage to the point that when it is started a number of diagnostic codes will set and the check engine light or service soon light will light up.
My coach cannot sit without being connected to shore power for more than a few days before the batteries are low and it will not start. There are master switches to prevent this from happening. If your towed vehicle is not driven for a week or more you may have a similar situation.
When I leave my automotive toys for a while I usually charge them and before leaving disconnect the batteries. The last time I left, disconnected the batteries but did not charge the batteries. My 1964 vehicle started right up but the 2003 started but the voltage was 11.8 upon startup. This low voltage set off 12 diagnostic codes. All of the codes were low voltage related.
Now this was not a problem for me as I suspected what was wrong. I fully charged the battery and reset the codes. After driving the vehicle for a few days none of the codes returned. You can save yourself a potential trip to a repair shop if you just remember to keep your batteries fully charged.
Most traditional wet cell batteries are fully charged at 13.2 volts. This voltage is as soon as it comes off a battery charging device. After it has sat for 12-24 hours it should be 12.7 to be fully charged. Some of the non-traditional (lead-acid filled) batteries are fully charged at 13.2 volts after setting. If a battery voltage drops below 12.4 internal damage may occur. I will go into this in another article on “Batteries”.
So make sure that you keep you batteries fully charged in all of your vehicles. Driving them is a good way to prevent issues while on the road. Another thing that I do is carry a battery charger and what is called a “Jump Box” or “Portable Jump Starter/Battery Pack. Battery chargers range in price from $30.00 to about $300.00 for portable units that will fit in an RV and the jump boxes range from $40.00 to $125.00 depending on the options you add and the number of peak amps. I have seen some that have a jump starter, work light, power supply, air compressor and an inverter. I will discuss these in depth in another article.
Along with computers came some changes in the automotive electrical systems. For years the majority of things on an automobile were wired so that the switch powered the circuit and power went to the load (light, radio, etc.) then to ground. In addition, many appliances or lights were mounted to a ground source. Now many circuits are powered and the switch connects to ground so a good ground is very important. General Motors issued a Technical Services Bulletin a few years ago and instructed technicians to remove all star washers factory installed on ground connections if any problems were found. They were further instructed to remove any paint between the ground source and the ground wiring connection.
So take a little time and make sure that all of your vehicle batteries are fully charged before heading out on your next adventure. Also remember that use care when working around your battery. When jump starting another vehicle refer to the “dead “battery vehicles owner’s manual for the correct connection procedure.
The most common method is as follows:
- Make sure that both vehicles are in Park or Neutral and the Parking Brakes are on.
- Shut off the engine in the booster or vehicle with the good battery.
- Make sure that all accessories in both vehicles are turner off.
- With the positive and negative connector of one end of the jumper cable set connect the positive clamp to the positive terminal of the good battery.
- While preventing the negative clamps from touching anything metallic, connect the other positive clamp to the positive terminal of the dead battery.
- Connect the negative clamp of the good battery end of the jumper cable set to the negative terminal of the good battery.
- Connect the negative clamp of the other end of the cable set to a clean metal part of the engine in the vehicle with the dead battery.
- Double check the connections and start the vehicle with the good battery and let it run for a few minutes.
- Now try to start the vehicle with the dead battery. If the battery is good and has been drained by leaving a light on or something like that it should start fairly quickly. If it starts slowly or fails to start, the battery is most likely beyond revival. Unless you know the reason for a dead battery, always check or have the electrical system checked for proper charging and the battery checked to make sure that it will hold a charge.
- After the vehicle with the dead battery starts, drive it for 20 minutes or more to ensure that it gets a proper charge.
- Disconnect the cables in the reverse order again remembering to not let any cables touch anything metallic until all cables are disconnected.
Keep positive thoughts and positive current flowing thru your life and vehicles and your life will be happier.